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This study analyzes the regulatory mechanism of oxygen vacancy concentration on tail-to-tail charged domain walls (T–T CDWs), along with the writing time, conduction current magnitude, and retention performance of through-type T–T CDWs. The research results show that the highest density and length of T–T CDWs are achieved when the oxygen vacancy concentration is 1 × 1020 cm−3. Moreover, the successful writing of through-type T–T CDWs is limited to a certain electric field range, which is controlled by oxygen vacancy concentration. An increase in the oxygen vacancy concentration leads to a decrease in the maximum and minimum threshold electric fields required for writing through-type charged domain walls. The writing time and conductivity of through-type T–T CDWs determine the information writing speed and signal strength of domain wall memories, and the oxygen vacancy concentration also plays a regulatory role in both aspects. When the oxygen vacancy concentration is 1 × 1020 cm−3, the through-type T–T CDW exhibits the fastest writing speed, requiring only 8 ns. The magnitude of the conduction current of through-type T–T CDWs is directly proportional to the oxygen vacancy concentration. The through-type T–T CDWs formed by the aggregation of oxygen vacancies exhibit excellent retention performance, making them highly promising for applications in ferroelectric domain wall memories. Our research demonstrates that oxygen vacancies have a significant regulatory effect on the morphology and current response of charged domain walls, opening up new avenues for the study of domain wall memories. [ABSTRACT FROM AUTHOR]

With the popularization of container technology, large-scale Docker public registries use object storage services to solve the problem of the sharp increasement in the number of images, but this loosely coupled registry design results in higher latency overhead. A cache prefetching strategy named LCPA (layer correlation prefetch algorithm) is proposed based on the correlation of image layers to enhance registry performance. When the registry server cache misses, LCPA creates the storage structure of layer by analyzing image metadata and calculates it by the correlation model to obtain the set of relevant layers. Finally, the registry actively prefetches the set from the back-end storage to the memory to improve the cache hit ratio. Experiment uses the Docker trace collected in real production workloads to test algorithm. The results show that LCPA outperforms the traditional cache algorithms, such as LRU, LIRS and GDFS etc., improves the average cache hit ratio by 12%-29% and increases the average latency saving by 21.1%-49.4%. Compared with the existing LPA prefetching algorithm, LCPA improves the cache hit ratio by 25.6%. Simulation experiments show that LCPA can effectively utilize the cache, greatly improves the cache hit ratio of Docker registry, and reduces the latency overhead of pulling images.

NAND flash based solid state disks (SSD) have better performance than magnetic disks and are gradually replacing hard disks in desktop systems. However, although DRAM is embedded in SSD as a buffer, SSD may also produce unstable write performance with continuous writing, because non-overwrite write and garbage collection(GC) operations are frequently triggered when physical pages are written. Aiming at this problem, a new flash buffer management strategy called PRLRU (least recently used algorithm by page reconstruction) is proposed, which manages the buffer through the page reconstruction mechanism and the data temperature recognition mechanism. The page reconfiguration mechanism combines pages with valid data that are less than one page size with other pages and then writes back to the flash memory to reduce the actual write operation by minimizing the number of non-overwrite write operations. The data temperature recognition mechanism performs temperature level marking on the cached pages, and then writes back the pages in a predetermined priority order. Test it with real workloads, the experimental results show that PRLRU can effectively improve SSD performance and prolong SSD lifetime. Compared with LRU, BPLRU and 2QW-Clock, the write performance of PRLRU is increased by 34.5%, 22.8% and 28.8%, respectively on average, the read performance increased by 12.5%, 10.6% and 8.3%, respectively on average, and the amount of garbage collection decreased by 10.5%, 8.7% and 6.3%, respectively on average.

Congenital dysfibrinogenemia (CD) is a rare hereditary fibrinogen disorder characterized by normal fibrinogen antigen levels associated with lower functional activities. The aim of this study is to analyze the phenotype and genotype of a family of CD. Routine coagulation screening tests were performed on the proband, her parents, and her grandparents. Then, the purified genomic DNA extracted from peripheral blood was amplified by PCR, and Sanger sequencing was performed to further confirm the mutation. The prothrombin time and activated partial thromboplastin time of the proband were normal, thrombin time prolonged, and the activity of fibrinogen (Fg:Ac) decreased significantly, but fibrinogen antigen (Fg:Ag) level was normal. The coagulation function indices of the proband’s father and grandfather were similar to her, and the indices of her mother and grandmother were normal. Sequencing results showed that the proband had a heterozygous missense mutation in FGA gene c.92G > A, which caused the mutation of amino acid 31 from glycine to glutamic acid (p.Gly31Glu). Her father had the same heterozygous mutation. In conclusion, the proband suffered from CD. The change of Gly31Glu in A chain due to the c.92G > A heterozygous missense mutation in the FGA gene is the cause of CD in the family. To the best of our knowledge, the mutation site is new and first reported so far.

Multiple myeloma (MM) is an immunoglobulin-producing tumor of plasma cells, which occurs commonly in the elderly. The incidence of myocardial amyloidosis with MM is extremely low and early clinical manifestations are nonspecific. The diversity of clinical manifestations and first episode symptoms often cause misdiagnosis in young patients with myocardial amyloidosis following MM. In this study, we analyzed the clinical data of a young woman with MM and impaired cardiac function combined with echocardiography, electrocardiography (ECG), laboratory data, cell Congo Red staining, and other manifestations to diagnose amyloidosis. Considering the rapid progression, short survival, and poor prognosis in most patients, a clear, definitive, and timely diagnosis is essential for the treatment of patients with MM complicated with myocardial amyloidosis.