87 research outputs found
Dynamic Evolution and Correlation between Metabolites and Microorganisms during Manufacturing Process and Storage of Fu Brick Tea
Fu brick tea (FBT) is one of the major brands of dark tea. Microbial fermentation is considered the key step in the development of the special characteristics of FBT. The systemic corelationship of the microbiome and metabolomics during manufacture of Fu brick tea is not fully understood. In this study, we comprehensively explored the microbiome and metabolite dynamic evolution during the FBT manufacturing processes, and revealed decisive factors for the quality and safety of FBT based on the grouped methods of metabolomics combined with biochemical measurements, microbiome sequencing combined with quantitative polymerase chain reaction (PCR), and multiplex analysis. Both the microbiome and quantitative PCR showed that fungi displayed concentrated distribution characteristics in the primary dark tea samples, while bacterial richness increased during the flowering processes and ripening period. All microorganism species, as well as dominant fungi and bacteria, were identified in the distinct processes periods. A total of 178 metabolites were identified, and 34 of them were characterized as critical metabolites responsible for metabolic changes caused by the corresponding processes. Metabolic analysis showed that most metabolites were decreased during the FBT manufacturing processes, with the exception of gallic acid. Multivariate analysis verified that the critical metabolites were correlated with specific dominant microbial species. All the top fungal species except unclassified_g_ Aspergillus showed positive correlations with six critical metabolites (L-The, epigallocatechin (EGC), Gln, tea polyphenol (TP), tea polysaccharides (TPs) and caffeine). Five of the top bacteria species (Cronobacter, Klebsiella, Pantoea, Pluralibacter, and unclassified_ f_Entero-bacteriaceae) showed positive correlations with epigallocatechins and tea polyphenols, while the other 11 top bacterial species correlated negatively with all the critical metabolites. The content of amino acids, tea polyphenols, tea polysaccharides, and flavonoids was reduced during microbial fermentation. In conclusion, our results reveal that microbial composition is the critical factor in changing the metabolic profile of FBT. This discovery provides a theoretical basis for improving the quality of FBT and enhancing its safety
Unsupervised Polychromatic Neural Representation for CT Metal Artifact Reduction
Emerging neural reconstruction techniques based on tomography (e.g., NeRF,
NeAT, and NeRP) have started showing unique capabilities in medical imaging. In
this work, we present a novel Polychromatic neural representation (Polyner) to
tackle the challenging problem of CT imaging when metallic implants exist
within the human body. The artifacts arise from the drastic variation of
metal's attenuation coefficients at various energy levels of the X-ray
spectrum, leading to a nonlinear metal effect in CT measurements.
Reconstructing CT images from metal-affected measurements hence poses a
complicated nonlinear inverse problem where empirical models adopted in
previous metal artifact reduction (MAR) approaches lead to signal loss and
strongly aliased reconstructions. Polyner instead models the MAR problem from a
nonlinear inverse problem perspective. Specifically, we first derive a
polychromatic forward model to accurately simulate the nonlinear CT acquisition
process. Then, we incorporate our forward model into the implicit neural
representation to accomplish reconstruction. Lastly, we adopt a regularizer to
preserve the physical properties of the CT images across different energy
levels while effectively constraining the solution space. Our Polyner is an
unsupervised method and does not require any external training data.
Experimenting with multiple datasets shows that our Polyner achieves comparable
or better performance than supervised methods on in-domain datasets while
demonstrating significant performance improvements on out-of-domain datasets.
To the best of our knowledge, our Polyner is the first unsupervised MAR method
that outperforms its supervised counterparts.Comment: 19 page
Automated Generation of Masked Nonlinear Components: From Lookup Tables to Private Circuits
Masking is considered to be an essential defense mechanism against side-channel attacks, but it is challenging to be adopted for hardware cryptographic implementations, especially for high security orders. Recently, Knichel et al. proposed an automated tool called AGEMA that enables the generation of masked implementations in hardware for arbitrary security orders using composable gadgets. This accelerates the construction and practical application of masking schemes. This article proposes a new automated tool named AGMNC that can generate masked nonlinear components with much better performance. The effectiveness of AGMNC is evaluated in several case studies. The evaluation results show a significant performance improvement, particularly for the first-order secure SKINNY S-box: saving 41 area, 25 latency, and 49 dynamic power. We achieve such a good result by integrating three key techniques: a new composable AND-XOR gadget, an optimization strategy based on the latency asymmetry feature of the AND-XOR gadget, and an implementation optimization for synchronization. Besides, we use the formal verification tool SILVER and FPGA-based practical experiments to confirm the security of the masked implementations generated by AGMNC
Case report: Cryoablation as a novel bridging strategy prior to CAR-T cell therapy for B cell malignancies with bulky disease
Chimeric antigen receptor (CAR) T-cell therapy has emerged as a powerful immunotherapy in relapsed/refractory (R/R) hematological malignancies, especially in R/R B-cell acute lymphocytic leukemia (B-ALL), non-Hodgkin lymphoma (NHL), and multiple myeloma (MM). To prevent disease progression and reduce tumor burden during CAR-T cell manufacturing, bridging therapies prior to CAR-T cell infusion are crucial. At present, it has been demonstrated that targeted therapy, radiotherapy and autologous stem cell transplantation (ASCT) could serve as effective bridging strategies. However, whether cryoablation could serve as a novel bridging strategy is unknown. In this paper, we report 2 cases of R/R B cell malignancies with bulky disease that were successfully treated with a combination of cryoablation and CAR-T cell therapy. Patient 1 was a 65-year-old female who was diagnosed with R/R MM with extramedullary disease (EMD). She was enrolled in the anti-BCMA CAR-T cell clinical trial. Patient 2 was a 70-year-old man who presented with a subcutaneous mass in the right anterior thigh and was diagnosed with primary cutaneous diffuse large B cell lymphoma, leg type (PCLBCL-LT) 1 year ago. He failed multiline chemotherapies as well as radiotherapy. Thus, he requested anti-CD19 CAR-T cell therapy. Unfortunately, they all experienced local progression during CAR-T cell manufacturing. To rapidly achieve local tumor control and reduce tumor burden, they both received cryoablation as a bridging therapy. Patient 1 achieved a very good partial response (VGPR) 1 month after CAR-T cell infusion, and patient 2 achieved a partial response (PR) 1 month after CAR-T cell infusion. In addition, adverse effects were tolerable and manageable. Our study demonstrated the favorable safety and efficacy of combination therapy with cryoablation and CAR-T cell therapy for the first time, and it also indicates that cryoablation could serve as a novel therapeutic strategy for local tumor control in B cell malignancies
New SAT-based Model for Quantum Circuit Decision Problem: Searching for Low-Cost Quantum Implementation
In recent years, quantum technology has been rapidly developed. As security analyses for symmetric ciphers continue to emerge, many require an evaluation of the resources needed for the quantum circuit implementation of the encryption algorithm. In this regard, we propose the quantum circuit decision problem, which requires us to determine whether there exists a quantum circuit for a given permutation f using M ancilla qubits and no more than K quantum gates within the circuit depth D. Firstly, we investigate heuristic algorithms and classical SAT-based models in previous works, revealing their limitations in solving the problem. Hence, we innovatively propose an improved SAT-based model incorporating three metrics of quantum circuits. The model enables us to find the optimal quantum circuit of an arbitrary 3 or 4-bit S-box under a given optimization goal based on SAT solvers, which has proved the optimality of circuits constructed by the tool, LIGHTER-R. Then, by combining different criteria in the model, we find more compact quantum circuit implementations of S-boxes such as RECTANGLE and GIFT. For GIFT S-box, our model provides the optimal quantum circuit that only requires 8 gates with a depth of 31. Furthermore, our model can be generalized to linear layers and improve the previous SAT-based model proposed by Huang et al. in ASIACRYPT 2022 by adding the criteria on the number of qubits and the circuit depth
Pushing the Limits: Searching for Implementations with the Smallest Area for Lightweight S-Boxes
The area is one of the most important criteria for an S-box in hardware implementation when designing lightweight cryptography primitives. The area can be well estimated by the number of gate equivalent (GE). However, to our best knowledge, there is no efficient method to search for an S-box implementation with the least GE. Previous approaches can be classified into two categories, one is a heuristic that aims at finding an implementation with a satisfying but not necessarily the smallest GE number; the other one is SAT-based focusing on only the smallest number of gates while it ignored that the areas of different gates vary. Implementation with the least gates would usually not lead to the smallest number of GE.
In this paper, we propose an improved SAT-based tool targeting optimizing the number of GE of an S-box implementation. Given an S-box, our tool can return the implementation of this S-box with the smallest number of GE. We speed up the search process of the tool by bit-sliced technique. Additionally, our tool supports 2-, 3-, and 4-input gates, while the previous tools cover only 2-input gates. To highlight the strength of our tool, we apply it to some 4-bit and 5-bit S-boxes of famous ciphers. We obtain a better implementation of RECTANGLE\u27s S-box with the area of 18.00GE. What\u27s more, we prove that the implementations of S-boxes of PICCOLO, SKINNY, and LBLOCK in the current literature have been optimal. When using the DC synthesizer on the circuits produced by our tool, the area are much better than the circuits converted by DC synthesizers from the lookup tables (LUT). At last, we use our tool to find implementations of 5-bit S-boxes, such as those used in KECCAK and ASCON
Distinguishing two-component anomalous Hall effect from topological Hall effect in magnetic topological insulator MnBi2Te4
In transport, the topological Hall effect (THE) is widely interpreted as a
sign of chiral spin textures, like magnetic skyrmions. However, the
co-existence of two anomalous Hall effects (AHE) could give rise to similar
non-monotonic features or "humps", making it difficult to distinguish between
the two. Here we demonstrate that the "artifact" two-component anomalous Hall
effect can be clearly distinguished from the genuine topological Hall effect by
three methods: 1. Minor loops 2. Temperature dependence 3. Gate dependence. One
of the minor loops is a single loop that cannot fit into the full AHE loop
under the assumption of AHE+THE. In addition, by increasing the temperature or
tuning the gate bias, the emergence of humps is accompanied by a polarity
change of the AHE. Using these three methods, one can find the humps are from
another AHE loop with a different polarity. Our material is a magnetic
topological insulator MnBi2Te4 grown by molecular beam epitaxy, where the
presence of the secondary phase MnTe2 on the surface contributes to the extra
positive AHE component. Our work may help future researchers to exercise
cautions and use these three methods to examine carefully in order to ascertain
genuine topological Hall effect
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