The Design and Construction of Public Service Building in Developing Rural Regions During the Post COVID-19 Period: Cased on a Chinese Village Centre

The spread of COVID-19 has caused an increasing demand for public medical room. Cases of Chinese Huoshenshan Hospital and mobile cabin hospitals proved the effectiveness of constructing emergent medical buildings. However, these cases, usually with strict requirements on technology and infrastructure, are hard to implement in developing rural regions. Therefore, there is an urgent need for adapting industrial construction to the rural situation. This research introduced an adaptive approach for rural projects delivery during COVID-19. It is based on a longitudinal case study, recording and analysing the construction process of a village centre in Jiangsu, China, from 2019 to 2020. By comparing the construction process of actual operation and traditional method, the advantages in a shorter building period and lower labour density were verified. This research pointed out neglected risks in developing countries and provided a practical construction approach in these areas. It supported the prevention of COVID-19 global wide

Differentially Private Bias-Term only Fine-tuning of Foundation Models

We study the problem of differentially private (DP) fine-tuning of large pre-trained models -- a recent privacy-preserving approach suitable for solving downstream tasks with sensitive data. Existing work has demonstrated that high accuracy is possible under strong privacy constraint, yet requires significant computational overhead or modifications to the network architecture. We propose differentially private bias-term fine-tuning (DP-BiTFiT), which matches the state-of-the-art accuracy for DP algorithms and the efficiency of the standard BiTFiT. DP-BiTFiT is model agnostic (not modifying the network architecture), parameter efficient (only training about $0.1\%$ of the parameters), and computation efficient (almost removing the overhead caused by DP, in both the time and space complexity). On a wide range of tasks, DP-BiTFiT is $2\sim 30\times$ faster and uses $2\sim 8\times$ less memory than DP full fine-tuning, even faster than the standard full fine-tuning. This amazing efficiency enables us to conduct DP fine-tuning on language and vision tasks with long-sequence texts and high-resolution images, which were computationally difficult using existing methods

On the accuracy and efficiency of group-wise clipping in differentially private optimization

Recent advances have substantially improved the accuracy, memory cost, and training speed of differentially private (DP) deep learning, especially on large vision and language models with millions to billions of parameters. In this work, we thoroughly study the per-sample gradient clipping style, a key component in DP optimization. We show that different clipping styles have the same time complexity but instantiate an accuracy-memory trade-off: while the all-layer clipping (of coarse granularity) is the most prevalent and usually gives the best accuracy, it incurs heavier memory cost compared to other group-wise clipping, such as the layer-wise clipping (of finer granularity). We formalize this trade-off through our convergence theory and complexity analysis. Importantly, we demonstrate that the accuracy gap between group-wise clipping and all-layer clipping becomes smaller for larger models, while the memory advantage of the group-wise clipping remains. Consequently, the group-wise clipping allows DP optimization of large models to achieve high accuracy and low peak memory simultaneously

Methylation status of individual CpG sites within Alu elements in the human genome and Alu hypomethylation in gastric carcinomas

<p>Abstract</p> <p>Background</p> <p><it>Alu </it>methylation is correlated with the overall level of DNA methylation and recombination activity of the genome. However, the maintenance and methylation status of each CpG site within <it>Alu </it>elements (<it>Alu</it>) and its methylation status have not well characterized. This information is useful for understanding natural status of <it>Alu </it>in the genome and helpful for developing an optimal assay to quantify <it>Alu </it>hypomethylation.</p> <p>Methods</p> <p>Bisulfite clone sequencing was carried out in 14 human gastric samples initially. A <it>Cac</it>8I COBRA-DHPLC assay was developed to detect methylated-<it>Alu </it>proportion in cell lines and 48 paired gastric carcinomas and 55 gastritis samples. DHPLC data were statistically interpreted using SPSS version 16.0.</p> <p>Results</p> <p>From the results of 427 <it>Alu </it>bisulfite clone sequences, we found that only 27.2% of CpG sites within <it>Alu </it>elements were preserved (4.6 of 17 analyzed CpGs, A ~ Q) and that 86.6% of remaining-CpGs were methylated. Deamination was the main reason for low preservation of methylation targets. A high correlation coefficient of methylation was observed between <it>Alu </it>clones and CpG site J (0.963), A (0.950), H (0.946), D (0.945). Comethylation of the sites H and J were used as an indicator of the proportion of methylated-<it>Alu </it>in a <it>Cac</it>8I COBRA-DHPLC assay. Validation studies showed that hypermethylation or hypomethylation of <it>Alu </it>elements in human cell lines could be detected sensitively by the assay after treatment with 5-aza-dC and M.<it>Sss</it>I, respectively. The proportion of methylated-<it>Alu </it>copies in gastric carcinomas (3.01%) was significantly lower than that in the corresponding normal samples (3.19%) and gastritis biopsies (3.23%).</p> <p>Conclusions</p> <p>Most <it>Alu </it>CpG sites are deaminated in the genome. 27% of <it>Alu </it>CpG sites represented in our amplification products. 87% of the remaining CpG sites are methylated. <it>Alu </it>hypomethylation in primary gastric carcinomas could be detected with the <it>Cac</it>8I COBRA-DHPLC assay quantitatively.</p

Design of Novel Reconfigurable Reflectarrays with Single-bit Phase Resolution for Ku-Band Satellite Antenna Applications

Reconfigurable reflectarray antennas operating in Ku-band are presented in this paper. First, a novel multilayer unit-cell based on polarization turning concept is proposed to achieve the single-bit phase shift required for reconfigurable reflectarray applications. The principle of the unit-cell is discussed using the current model and the space match condition, along with simulations to corroborate the design and performance criteria. Then, an offset-fed configuration is developed to verify performance of the unit-cell in antenna application, and its polarization transformation property is elaborated. Finally, an offset-fed reflectarray with 10×10 elements is developed and fabricated. The dual-polarized antenna utilizes the control code matrices to accomplish a wide angle beam-scanning. A full wave analysis is applied to the reflectarray, and detailed results are presented and discussed. This electronically steerable reflectarray antenna has significant potential for satellite applications, due to its wide operating band, simple control and beam-scanning capability