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Addressing the issues of prolonged training times and low recognition rates in large model applications, this paper proposes a weight training method based on entropy gain for weight initialization and dynamic adjustment of the learning rate using the multilayer perceptron (MLP) model as an example. Initially, entropy gain was used to replace random initial values for weight initialization. Subsequently, an incremental learning rate strategy was employed for weight updates. The model was trained and validated using the MNIST handwritten digit dataset. The experimental results showed that, compared to random initialization, the proposed initialization method improves training effectiveness by 39.8% and increases the maximum recognition accuracy by 8.9%, demonstrating the feasibility of this method in large model applications.

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Ceramizable silicone rubber (CSR) composed of silicone rubber matrix and inorganic fillers can be transformed into a dense flame-retardant ceramic upon encountering high temperatures or flames. Conventionally, CSR can be sintered into a dense ceramic at temperatures above 1000 °C, which is higher than the melting point of a copper conductor used in a power cable. In this study, the vulcanization process and mass ratio of inorganic fillers of CSR were studied to lower its ceramization temperature to 950 °C. The electrical and mechanical properties of CSRs and their ceramic bulks were studied with various ratios of wollastonite and muscovite. It was found that the CSR samples could be successfully fabricated using a two-step vulcanization technique (at 120 °C and 150 °C, respectively). As a high ratio of muscovite filler was introduced into the CSR, the sample presented a high dc electrical resistivity of 6.713 × 1014 Ω·cm, and a low dielectric constant of 4.3 and dielectric loss of 0.025 at 50 Hz. After the thermal sintering (at 950 °C for 1 h) of the CSR sample with a high ratio of muscovite, the ceramic sample exhibits a dense microstructure without any pores. The ceramic also demonstrates excellent insulating properties, with a volume resistivity of 8.69 × 1011 Ω·cm, and a low dielectric loss of 0.01 at 50 Hz. Meanwhile, the three-point bending strength of the ceramic sample reaches a value of 110.03 MPa. This study provides a potential route to fabricate CSR used for fire-resistant cables.

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In order to evaluate the role of positron emission tomography (PET) with N-methyl-[(11)C]-2-(4'-methylaminophenyl)-6-hydroxybenzothiazole, also known as Pittsburgh compound B (PIB), in the early diagnosis of Alzheimer's disease (AD). Clinical data were collected, and PIB PET cerebral imaging was performed in patients with AD (n = 6), mild cognitive impairment (MCI) (n = 7), and elderly, mentally normal controls (NCs) (n = 7). PET images of the subjects were then analyzed. Visual analysis showed that the radioactivity clearance rate in AD patients was significantly different from that found in the NC group. Furthermore, the radioactivity clearance rate 45 min after PIB injection was significantly lower than the NC group. Images from the MCI group presented heterogeneous results, overlapping with those from both the AD and NC groups. Statistical analysis showed that the radioactivity clearance rate during 5-45 min post-injection was significantly lower in the AD group (41-77%) than the control group (75-81%) (P > 0.05) and the MCI group (59-77%). The radioactivity clearance rate in the bilateral parietal lobes, frontal, temporal, and right occipital lobes, and the bilateral corpora striata in MCI group were lower than that in control group (P < 0.05). PIB PET brain imaging can differentiate early AD patients from NCs and may have certain value in identifying patients progressing to MCI.

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OBJECTIVE: To evaluate the clinical efficacy and safety of akatinol memantine in the treatment of patients with mild to moderate Alzheimer disease (AD). METHODS: One hundred patients with diagnosis of possible or probable AD and Mini Mental State Examination total scores between 10 and 26 from 6 centers in two cities of China were randomly divided into two groups: akatinol memantine group (n = 50, given akatinol memantine 5 mg/d in first week, 10 mg/d in second week, 15 mg/d in third week and 20 mg/d from fourth to sixteenth week); donepezil group (n = 50, donepezil 5 mg/d). Different scales were used to evaluated cognitive function (MMSE), activity of daily life and behavior and mood (Blessed-Roth scale) as well as the severity of dementia (GDS). Safety evaluation was conducted every 4 weeks. RESULTS: In comparison with the baseline data, there were significant improvements in cognition assessed with MMSE on 16th week in akatinol memantine group (P = 0.000) and donepezil group (P = 0.000) respectively; There also were significant improvements in activity of daily life, behavior and mood assessed by Blessed-Roth scale in akatinol memantine group (P = 0.000) and donepezil group (P = 0.000) on 8th week and 16th week. However there was no improvements in the change of the basic habit of life assessed with the Part II of Blessed-Roth scale (P > 0.05), and nor an improvements in the serious level of dementia assessed with GDS (P > 0.05). In comparison with the data in donepezil group, there were no improvement in the change of MMSE score, Blessed-Roth scale score and GDS score in akatinol memantine group on 16th week (P > 0.05). Mild and transient adverse events were observed in 6% of akatinol memantine group. CONCLUSION: As a safe and effective medicine, akatinol memantine, which has a similar effect as donepezil for AD, can remarkably improve the cognition, behavior, and mood of AD patients.

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OBJECTIVE: To study cognitive function and cerebral metabolic changes in patients with transient global amnesia (TGA). METHODS: Three patients with TGA were given mini-mental state examination (MMSE), revised Wechsler memory scale (WMS-R) examination and magnetic resonance imaging (MRI) scans after they had been diagnosed as TGA. Using (18)F labelled deoxyglucose as tracer, patients were given a positron emission tomography (PET) examination at different periods during recovery. RESULTS: No obvious abnormality was found in MMSE and MRI scans in the three patients. However, WMS-R examination and cerebral PET imaging displayed cognitive dysfunction of varying degrees and low metabolism in local areas related to memory in 2 of 3 patients. CONCLUSIONS: In TGA patients, cognitive function and cerebral metabolic levels are closely correlated with duration of symptoms. It is necessary to stop the TGA attack as quickly as possible early time.

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