Engineered Macrophages Tune Intratumoral Cytokines through Precisely Controlled Self-Pyroptosis to Enhance Bladder Cancer Immunotherapy.

Engineered macrophages are a promising tool for drug delivery and immunotherapy in cancer treatment. However, simultaneous targeted enrichment and controllable immunological activation of these macrophages at the tumor site remains challenging. As a solution, macrophages loaded with an advanced nanoparticle encapsulating CpG-conjugated magnetic nanoclusters (MNC) with indocyanine green (ICG) and nigericin (NIG) (MNC-ICG-NIG@SiO2 (MINS)), utilizing Se─Se bond-modified SiO2, are designed and applied in bladder cancer, which is typically managed surgically, followed by Bacillus Calmette-Guerin (BCG) adjuvant instillation therapy. Upon intravenous administration, BCG-mediated tumor-localized inflammation leads to targeted accumulation of MINS@MΦ. MINS@MΦ accumulates within the tumor tissue and is immunologically activated through laser irradiation, leading to ICG-mediated generation of reactive oxygen species, Se─Se bond cleavage, and subsequent NIG release to induce self-pyroptosis. Consequently, MINS@MΦ releases Fe2+ ions and CpG, thus promoting the M1 polarization of tumor-associated macrophages and secretion of appropriate antitumor cytokines. However, without intervention, MINS@MΦ undergoes apoptosis in the bloodstream after 48 h without eliciting any immune response. Therefore, this innovative approach optimizes and enhances the efficacy of BCG immunotherapy by precisely modulating the cytokines for effective bladder cancer treatment without inducing a systemic inflammatory response.

Homochiral Nanopropeller via Chiral Active Surface Growth.

Under the control of chiral ligand glutathione and in the presence of hexadecyltrimethylammonium bromide, Au deposition on Au seeds is known to give chiral nanostructures. We have previously shown that the protruding chiral patterns, as opposed to flat facets, are likely caused by active surface growth, where nonuniform ligand coverage could be responsible for the focused growth at a few active sites. By pushing the limit of such a growth mode, here, we use decahedral seeds to prepare homochiral nanopropellers with intricate patterns of deep valleys and protruding ridges. Control experiments show that the focused growth depends on the rates of Au deposition by changing either the seed concentration or the reductant concentration, consistent with the proposed mechanism. The dynamic growth competition between the ligand-deficient active sites and the ligand-rich surfaces gradually focuses the growth onto a few active sites, causing the expansion of grooves, squeezing of steep ridges, and a surprising 36° rotation of the pentagonal outline. The imbalanced deposition on the prochiral slopes is responsible for the tilted grooves, the twisted walls, and thus the well-separated and distorted blades, which become the origin of the chiroptical responses.

BAR: Blockwise Adaptive Recoding for Batched Network Coding.

Multi-hop networks have become popular network topologies in various emerging Internet of Things (IoT) applications. Batched network coding (BNC) is a solution to reliable communications in such networks with packet loss. By grouping packets into small batches and restricting recoding to the packets belonging to the same batch; BNC has much smaller computational and storage requirements at intermediate nodes compared with direct application of random linear network coding. In this paper, we discuss a practical recoding scheme called blockwise adaptive recoding (BAR) which learns the latest channel knowledge from short observations so that BAR can adapt to fluctuations in channel conditions. Due to the low computational power of remote IoT devices, we focus on investigating practical concerns such as how to implement efficient BAR algorithms. We also design and investigate feedback schemes for BAR under imperfect feedback systems. Our numerical evaluations show that BAR has significant throughput gain for small batch sizes compared with existing baseline recoding schemes. More importantly, this gain is insensitive to inaccurate channel knowledge. This encouraging result suggests that BAR is suitable to be used in practice as the exact channel model and its parameters could be unknown and subject to changes from time to time.

Design and Analysis of Systematic Batched Network Codes.

Systematic codes are of important practical interest for communications. Network coding, however, seems to conflict with systematic codes: although the source node can transmit message packets, network coding at the intermediate network nodes may significantly reduce the number of message packets received by the destination node. Is it possible to obtain the benefit of network coding while preserving some properties of the systematic codes? In this paper, we study the systematic design of batched network coding, which is a general network coding framework that includes random linear network coding as a special case. A batched network code has an outer code and an inner code, where the latter is formed by linear network coding. A systematic batched network code must take both the outer code and the inner code into consideration. Based on the outer code of a BATS code, which is a matrix-generalized fountain code, we propose a general systematic outer code construction that achieves a low encoding/decoding computation cost. To further reduce the number of random trials required to search a code with a close-to-optimal coding overhead, a triangular embedding approach is proposed for the construction of the systematic batches. We introduce new inner codes that provide protection for the systematic batches during transmission and show that it is possible to significantly increase the expected number of message packets in a received batch at the destination node, without harm to the expected rank of the batch transfer matrix generated by network coding.

From flat to deep concave: an unusual mode of facet control.

Au particles with rhombic dodecahedron outlines and deep cavities are obtained by epitaxial growth from a triangular nanoplate. An unusual "wrapping" growth that combines ligand-promoted facet-selective growth and site-specific deposition is proposed. Such a templateless growth not only allows the extreme defect-tolerance, but also broadens the synthetic control at the nanoscale.

Targeted pandemic containment through identifying local contact network bottlenecks.

Decision-making about pandemic mitigation often relies upon simulation modelling. Models of disease transmission through networks of contacts-between individuals or between population centres-are increasingly used for these purposes. Real-world contact networks are rich in structural features that influence infection transmission, such as tightly-knit local communities that are weakly connected to one another. In this paper, we propose a new flow-based edge-betweenness centrality method for detecting bottleneck edges that connect nodes in contact networks. In particular, we utilize convex optimization formulations based on the idea of diffusion with p-norm network flow. Using simulation models of COVID-19 transmission through real network data at both individual and county levels, we demonstrate that targeting bottleneck edges identified by the proposed method reduces the number of infected cases by up to 10% more than state-of-the-art edge-betweenness methods. Furthermore, the proposed method is orders of magnitude faster than existing methods.

A Protocol Design Paradigm for Batched Sparse Codes.

Internet of Things (IoT) connects billions of everyday objects to the Internet. The mobility of devices can be facilitated by means of employing multiple wireless links. However, packet loss is a common phenomenon in wireless communications, where the traditional forwarding strategy undergoes severe performance issues in a multi-hop wireless network. One solution is to apply batched sparse (BATS) codes. A fundamental difference from the traditional strategy is that BATS codes require the intermediate network nodes to perform recoding, which generates recoded packets by network coding operations. Literature showed that advanced recoding schemes and burst packet loss can enhance and diminish the performance of BATS codes respectively. However, the existing protocols for BATS codes cannot handle both of them at the same time. In this paper, we propose a paradigm of protocol design for BATS codes. Our design can be applied in different layers of the network stack and it is compatible to the existing network infrastructures. The modular nature of the protocol can support different recoding techniques and different ways to handle burst packet loss. We also give some examples to demonstrate how to use the protocol.

Twisting Ultrathin Au Nanowires into Double Helices.

Previously, double helix nanowire was reported by coating Pd/Pt/Au onto Au-Ag alloy nanowire. Here, straight oleylamine-stabilized ultrathin Au nanowires with single crystalline fcc lattice are surprisingly converted into double helix helices upon reacting with Ag in tetrahydrofuran (THF). The obtained Au-Ag helical nanowires contain lattice distinctively different from the fcc lattice and are different in many aspects with the previous system. The discovery may expand the scope of nanoscale double helix formation and the understanding of lattice transformation among ultrafine nanostructures.