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Crossbar-based PIM DNN accelerators can provide massively parallel in-situ operations. A specifically designed compiler is important to achieve high performance for a wide variety of DNN workloads. However, some key compilation issues such as parallelism considerations, weight replication selection, and array mapping methods have not been solved. In this work, we propose PIMCOMP - a universal compilation framework for NVM crossbar-based PIM DNN accelerators. PIMCOMP is built on an abstract PIM accelerator architecture, which is compatible with the widely used Crossbar/IMA/Tile/Chip hierarchy. On this basis, we propose four general compilation stages for crossbar-based PIM accelerators: node partitioning, weight replicating, core mapping, and dataflow scheduling. We design two compilation modes with different inter-layer pipeline granularities to support high-throughput and low-latency application scenarios, respectively. Our experimental results show that PIMCMOP yields improvements of 1.6$\times$ and 2.4$\times$ in throughput and latency, respectively, relative to PUMA.

Phospholipids are the main constituent of cellular membranes and have recently been identified to have diagnostic value as biomarkers for many diseases. Accordingly, much emphasis is now laid on developing optimal analytical techniques for the phospholipid profiles of various biological samples. In the present study, different classes of phospholipids are first separated by optimized hydrophilic interaction chromatography with evaporative light scattering detector (HILIC-ELSD). The phospholipids in each class are then identified by ultraperformance liquid chromatography-quadrupole time-of-flight mass spectrometry (UPLC-Q-TOF-MS). Validation results confirm that this approach meets the requirements of quantitative analysis. Finally, the approach is adopted to analyze the phospholipid profiles in Caenorhabditis elegans. A total of 111 phospholipid species is identified according to the mass fragments. Major fatty acyl chains in phospholipids are found to be formed by oleic acid (C18:1), arachidonic acid (C20:4), and eicosapentaenoic acid (C20:5). Overall, this study improves current knowledge on analytical techniques of the phospholipid composition in C. elegans and provides a basis for future lipidomics research. Practical applications: Phospholipids reportedly play a crucial role in the development of many diseases. Until now, only a small portion of phospholipids in Caenorhabditis elegans has been reported by using one-dimensional analysis strategy. The offline 2D2D liquid chromatography method developed in this study identifies 111 phospholipid species in Caenorhabditis elegans. The obtained phospholipid profiles complement the lipid database of Caenorhabditis elegans. The study also provides the basis for the future development of a 2D online approach.

Additional file 1: Fig. S1. Overview of the constructed micro-chambers within collagen, and cells pattern in the micro-chambers. (A) Micro-chamber arrays with regular shape, and cells well-confined in them. Dashed squares mark the micro-chamber position. (B) Enlarged view of the micro-chambers and cells in them. Fig. S2. Cells morphology of A549 and HPAEpiCs on 2-D in vitro culture system. Fig. S3. Highly malignant breast cancer cells MDA-MB-231 cells and lung cancer cells A549 cultured in the micro-chambers of the constructed 3-D in vitro model. (A) MDA-MB-231 cells started to extend protrusions to invade into the surrounding collagen with high stiffness (high concentration of 6 mg/ml) as early as on Day 1 after seeding. The white arrow indicates one of the protrusions (invadopodia) outside of the micro-chambers. (B) A549 cells in micro-chambers (white dash-line indicating the chamber edge) started to extend protrusions/invadopodia (indicated by the yellow arrows) to invade into the surrounding collagen. The left image taken by laser confocal microscope only shows the cells channel, and the right image shows both channels of cells and collagen fibers.

Exosomal miRNAs are used as novel non-invasive biomarkers for detection strategies of human disease. Here, we aimed to investigate the potential clinical value of exosomal miRNAs for myocardial infarction (MI) diagnosis and treatment. Differentially expressed miRNAs were obtained from normal cardiomyocytes, MI cardiomyocytes and adjacent normal cardiomyocytes using miRNA microarray analysis. Exosomes were isolated by centrifugation and identified by transmission electron microscopy (TEM) and western blot. The expression of miR-328-3p in exosomes was then verified by qRT-PCR. Cell apoptosis was measured using flow cytometry and TUNEL analysis. The MI severity was confirmed by masson's trichrome staining and echocardiography. MiR-328-3p was significantly increased in the MI cardiomyocytes and adjacent normal cardiomyocytes. We further confirmed miR-328-3p increasing in the exosomes from MI cardiomyocytes, which can be taken into normal cardiomyocytes. Furthermore, exogenous exosomal miR-328-3p increased apoptosis of cardiomyocytes and promoted MI. Genes regulated by miR-328-3p are mainly enriched in Caspase signaling, which is an important apoptosis regulating signaling pathway. Additionally, Caspase-3 inhibitor, Z-DEVD-FMK, reversed apoptosis and MI promoting function of miR-328-3p. Exosomal miR-328-3p is a potential novel diagnostic biomarker and therapeutic target for MI, and Z-DEVD-FMK could reverse the apoptosis progression induced by miR-328-3p.

Twisted bilayers of van der Waals materials have recently attracted great attention due to their tunable strongly correlated phenomena. Here, we investigate the chirality-specific physics in 3D moir\'e superlattices induced by Eshelby twist. Our direct DFT calculations reveal helical rotation leads to optical circular dichroism, and chirality-specific nonlinear Hall effect, even though there is no magnetization or magnetic field. Both these phenomena can be reversed by changing the structural chirality. This provides a way to constructing chirality-specific materials.

Additional file 1. Additional information.

For a long time, two-dimensional (2D) hexagonal MoS2 was proposed as a promising material for valleytronic system. However, the limited size of growth and low carrier motilities in MoS2 restrict its further application. Very recently, a new kind of hexagonal 2D MXene, MoSi2N4, was successfully synthesized with large size, excellent ambient stability, and considerable hole mobility. In this paper, based on the first-principles calculations, we predict that the valley-contrast properties can be realized in monolayer MoSi2N4 and its derivative MoSi2As4. Beyond the traditional two-level valleys, the valleys in monolayer MoSi2As4 are multiple-folded, implying a new valley dimension. Such multiple-folded valleys can be described by a three-band low-power Hamiltonian. This study presents the theoretical advance and the potential applications of monolayer MoSi2N4 and MoSi2As4 in valleytronic devices, especially multiple information processing.

Valleytronics is a rising topic to explore the emergent degree of freedom for charge carriers in energy band edges and has attracted a great interest due to many intriguing quantum phenomena and potential application in information processing industry. Creation of permanent valley polarization, i.e. unbalanced occupation at different valleys, is a chief challenge and also urgent question to be solved in valleytronics. Here we predict that the spin-orbit coupling and magnetic ordering allow spontaneous valley Zeeman-type splitting in pristine monolayer of VAgP2Se6 by using first-principles calculations. The Zeeman-type valley splitting can lead to permanent valley polarization after suitable doping. The Zeeman-type valley splitting is similar to the role of spin polarization in spintronics and is a vital requirement for practical devices in valleytronics. The nonequivalent valleys of VAgP2Se6 monolayer can emit or absorb circularly polarized photons with opposite chirality, and thus this material shows a great potential to work as a photonic spin filter and circularly-polarized-light resource. A valley pseudospin field effect transistor (VPFET) is designed based on the monolayer VAgP2Se6 akin to the spin field effect transistors. Beyond common transistors, VPFETs carry information of not only the electrons but also the valley pseudospins.

An interfacial site-directed, capping-agent-free growth method for direct production of macromolecular scale (sub-5 nm) porous nanocrystals that are fully crystalline with a high surface area were developed for efficient biocatalysis., The direct production of macromolecular scale (sub-5 nm) porous nanocrystals with high surface area has been a considerable challenge over the past two decades. Here we report an interfacial site-directed capping agent-free growth method to directly produce porous ultrasmall (sub-5 nm), fully crystalline, macromolecular scale nanocrystals. The porous sub-5 nm Prussian blue nanocrystals exhibit uniform sizes (∼4 ± 1 nm), high surface area (∼855 m2 g–1), fast electron transfer (rate constant of ∼9.73 s–1), and outstanding sustained catalytic activity (more than 450 days). The nanocrystal-based biointerfaces enable unprecedented sub-nanomolar level recognition of hydrogen peroxide (∼0.5 nM limit of detection). This method also paves the way towards the creation of ultrasmall porous nanocrystals for efficient biocatalysis.

Over the last century, Chinese Foreign Direct Investments have made great impacts on African countries. Large amounts of FDI from China has flooded into African infrastructure investments, targeting key sectors such as telecommunications, transportation, power plants, and port refurbishments. No doubt China treats itself as an equal and a generous partner of African countries, yet not an uncontroversial one especially from the perspective of foreign observers. There have been many critical voices on China-Africa relations over the years. In order to test the validity of the critiques as well as the praises, two infrastructure construction projects were chosen as case studies in this thesis. They are the Standard Gauge Railroad and A109 national road. Both contracts were signed between the Kenyan government and a Chinese state-owned company, Chinese Road and Bridge Cooperation (CRBC). By analyzing the first hand data and some supplementary second hand data, it indicates that though CRBC as contractor had made some decisions based on self-interests, the critics of labor importation and resource plunder lack supporting evidence. Instead, for these particular projects, they generated positive economic impacts on national development. However, many improvements are highly recommended for both parties to make the projects better in the future.

Object: To investigate the effect of lung Ischemia-reperfusion injury on cardiac muscle. Methods: SD rats were randomly divided into the following four groups: sham operation group (TS group); experimental control group (TG group); curcumin group (TC group); dexamethasone group (TM group). After 4 h and 24 h of lung ischemia-reperfusion, the cardiac muscle was collected. We measured the concentrations of TNF-α, IL-6, caspase-3, antioxidant capacity and neutrophil infiltration in myocardial tissue. Results: After lung ischemia-reperfusion 4 h, TNF-α, IL-6 levels, MDA and neutriphils infiltration increased in myocardial tissue in control group, total antioxidant capacity decreased, and caspase-3 exhibited no significant changes. However, 24 h after reperfusion, there were no significant difference between the sham group and experimental group. Conclusion: Lung ischemia-reperfusion injury affected the function of cardiac muscle, especially 4 h after reperfusion. Curcumin and dexamethasone effectively protected myocardial injury after lung ischemia-reperfusion.

This report is the product of a semester-long urban planning studio focused on the informal settlement of Rio das Pedras in Rio de Janeiro, Brazil. Our client, Studio-X Rio commissioned this studio as part a 'Rio das Pedras Initiative' to examine and characterize this community and put forth proposals for its advancement within the realm of urban planning. The result is an extensive exploration of the present economy, living conditions, and culture of Rio das Pedras and its role within the city of Rio de Janeiro, through the eyes of the stakeholders involved in shaping the community.

The main objectives of Task Order 4136 are (1) the design of improved freeway on-ramp metering strategies that make use of recent developments in traffic data collection, traffic simulation, and control theory, and (2) the testing of these methods on a 14-mile segment of Interstate 210 Westbound in southern California. To date, the major accomplishments of this project include (i) the development of a complete procedure for constructing and calibrating a microscopic freeway traffic model using the Vissim microsimulator, which was applied successfully to the full I-210 test site, (ii) a simulation study, using the calibrated Vissim I-210 model, comparing the fixed-rate, Percent Occupancy, and Alinea local ramp metering schemes, which showed that Alinea can improve freeway conditions when mainline occupancies are measured upstream of the on-ramp (as on I-210 and most California freeways), as well as when occupancy sensors are downstream of the on-ramp, (iii) development of computationally efficient macroscopic freeway traffic models, the Modified Cell Transmission Model (MCTM) and Switching-Mode Model (SMM), validation of these models on a 2-mile segment of I-210, and determination of observability and controllability properties of the SMM modes, (iv) design of a semi-automated method for calibrating the parameters of the MCTM and SMM, which, when applied to an MCTM representation of the full I-210 segment, was able to reproduce the approximate behavior of traffic congestion, yielding about 2% average error in the predicted Total Travel Time (TTT), and (v) development of a new technique for generating optimal coordinated ramp metering plans, which minimizes a TTT-like objective function. Simulation results for a macroscopic model of the 14-mile I-210 segment have shown that the optimal plan predicts an 8.4% savings in TTT, with queue constraints, over the 5-hour peak period.