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We study the Schwinger model at finite-temperature regime using a quantum-classical hybrid algorithm. The preparation of thermal state on quantum circuit presents significant challenges. To address this, we adopt the Thermal Pure Quantum (TPQ) state approach and apply the Quantum Imaginary Time Evolution (QITE) algorithm to implement the necessary imaginary time evolution. We first compute the chiral condensate in the massless Schwinger model, verifying its consistency with the analytical solution. We then simulate the massive Schwinger model with non-zero topological $\theta$-term to investigate the temperature and $\theta$-dependence of the chiral condensate. Our method works well even at non-zero $\theta$ regime, while the conventional lattice Monte Carlo method suffers from the sign problem in this system., Comment: 7 pages, 4 figures, Proceedings of the 40th Lattice conference will take place at Fermilab, Batavia, Illinois, USA, from July 31 to August 4, 2023

We examine a wavefunction ansatz in which a doped hole can experience a quantum transition from a charge +e Landau quasiparticle to a neutral spinon as a function of the underlying spin-spin correlation. As shown variationally, such a wavefunction accurately captures all the essential features revealed by exact diagonalization and density matrix renormalization group simulations in a two-leg t-J ladder. Hence its analytic form can provide an explicit understanding of the mechanism for the unconventional ground state. The transition in the phase diagram is accompanied by a change of the hole composite from a tight charge-spin binding to a loosely-bound hole-spin pair. In the latter, the hole carries a finite spin current but with vanishing charge current in the degenerate ground states. We show that the charge of the hole composite here is dynamically diminished due to an internal relative hole-spin motion, which is fundamentally distinct from a simple charge-spin separation in a one-dimensional case. We further show that the same effect is also responsible for a strong pairing between two doped holes in such a non-Landau quasiparticle regime.

As an important carrier of healthcare data, Electronic Medical Records (EMRs) generated from various sensors, i.e., wearable, implantable, are extremely valuable research materials for artificial intelligence and machine learning. The efficient circulation of EMRs can improve remote medical services and promote the development of the related healthcare industry. However, in traditional centralized data sharing architectures, the balance between privacy and traceability still cannot be well handled. To address the issue that malicious users cannot be locked in the fully anonymous sharing schemes, we propose a trackable anonymous remote healthcare data storing and sharing scheme over decentralized consortium blockchain. Through an “on-chain & off-chain” model, it relieves the massive data storage pressure of medical blockchain. By introducing an improved proxy re-encryption mechanism, the proposed scheme realizes the fine-gained access control of the outsourced data, and can also prevent the collusion between semi-trusted cloud servers and data requestors who try to reveal EMRs without authorization. Compared with the existing schemes, our solution can provide a lower computational overhead in repeated EMRs sharing, resulting in a more efficient overall performance.

The authors regret that the image of the representative band of GAPDH in Figure 2C is mistakenly selected during figure composition. The corrected picture is as follows.

The authors regret that the image of the representative band of GAPDH in Figure 2C is mistakenly selected during figure composition. The corrected picture is as follows.

Information processing in the brain depends on specialized organization of neurotransmitter receptors and scaffolding proteins within the postsynaptic density. However, how these molecules are organized in situ remains largely unknown. In this study, template-free classification of oversampled sub-tomograms was used to analyze cryo-electron tomograms of hippocampal synapses. We identified type-A GABA receptors (GABAARs) in inhibitory synapses and determined their in situ structure at 19-Å resolution. These receptors are organized hierarchically: from GABAAR super-complexes with a preferred inter-receptor distance of 11 nm but variable relative angles, through semi-ordered, two-dimensional receptor networks with reduced Voronoi entropy, to mesophasic assembly with a sharp phase boundary. These assemblies likely form via interactions among postsynaptic scaffolding proteins and receptors and align with putative presynaptic vesicle release sites. Such mesophasic self-organization might allow synapses to achieve a 'Goldilocks' state, striking a balance between stability and flexibility and enabling plasticity in information processing.

The authors regret that the image of the representative band of GAPDH in Figure 2C is mistakenly selected during figure composition. The corrected picture is as follows.

Liqi Li, 1, 2,* Rong-Mao Sun, 1,* Guo-Qin Jiang 1 1Department of Surgery, The Second Affiliated Hospital of Soochow University, Suzhou, Jiangsu 215004, People’s Republic of China; 2Department of Thyroid Breast Surgery, Affiliated Hospital of Jiangnan University, Wuxi, Jiangsu 214062, People’s Republic of China*These authors contributed equally to this workCorrespondence: Guo-Qin Jiang Suzhou 215004, People’s Republic of ChinaTel/Fax +86-512-67784797Email jiang_guoqin@163.comIntroduction: Breast cancer is a common malignancy in females worldwide. In this study, we investigated the role of activating transcription factor 3 (ATF3) and ADP-ribosylation factor like-4 (ARL4) in human breast cancer, and the associated mechanisms.Materials and Methods: We measured ATF3 and ATL4C expressions in 15 paired breast cancer tissues using qRT-PCR, Western blotting and IHC. Cell growth, migration and invasion were tested in ATF3 or ARL4C overexpression breast cancer cells. TCGA database analysis was done to identify the correlation between ATF3 and ARL4C. We evaluated the binding of ATF3 to ARL4C promoter sequences and the effect of hypermethylation and demethylation of ATF3. A meta-analysis was done to investigate the relationship between the expression of ATF3 and/or ARL4C and the poor prognoses.Results: Our results showed that ATF3 and ARL4C were decreased in breast cancer specimens at both mRNA and protein levels. Restoration of ATF3 or ARL4C reduced breast cancer tumorigenesis, evidenced by decreased cell growth, migration and invasion. The expression of ATF3 was positively correlated with ARL4C in breast cancer specimens, and ATF3 was shown to bind to the ARL4C promoter sequences. Furthermore, the expression of ATF3 was negatively regulated by hypermethylation, and demethylation of ATF3 stimulated ATF3 expression, which further promoted ARL4C transcription. Finally, a meta-analysis showed that patients with breast cancer with low

Hyperglycaemia is known to impair angiogenesis, which may contribute to the poor prognosis of diabetic patients following myocardial infarction (MI). miR-17 has been reported to be involved in the proliferation, migration, and angiogenesis of a variety of vascular endothelial cells. However, how miR-17 regulates angiogenesis under hyperglycaemic conditions has not been reported. Thus, the aim of this study was to investigate the role of miR-17 in the impairment of angiogenesis induced by high glucose. In vitro, human umbilical vein endothelial cells (HUVECs)transfected with miR-17 mimics or inhibitors were incubated with normal-glucose or high-glucose (HG)medium. In vivo, miR-17 or negative control antagomirs were administered by tail vein injection in an MI model of streptozotocin (STZ)-induced diabetic mice. MiR-17 was upregulated, while VEGFA was downregulated in MI mice with diabetes and in HUVECs exposed to HG. The luciferase reporter gene assay confirmed that VEGFA is a target gene of miR-17. Moreover, inhibition of miR-17 prevented HG-induced VEGFA downregulation and impaired the capacity for migration and tube formation in HUVECs. Administration of miR-17 antagomirs significantly improved LV function and reduced infarct size in diabetic post-MI mice. Furthermore, the effects of diabetes-induced decreases in angiogenesis and VEGFA expression were abrogated by miR-17 antagomirs treatment in diabetic infarcted myocardium. These findings suggest that inhibition of miR-17 prevents HG-induced impairment of angiogenesis and improves cardiac function after MI by targeting VEGFA in diabetic mice. © 2019 Elsevier Inc.

Hyperglycaemia is known to impair angiogenesis, which may contribute to the poor prognosis of diabetic patients following myocardial infarction (MI). miR-17 has been reported to be involved in the proliferation, migration, and angiogenesis of a variety of vascular endothelial cells. However, how miR-17 regulates angiogenesis under hyperglycaemic conditions has not been reported. Thus, the aim of this study was to investigate the role of miR-17 in the impairment of angiogenesis induced by high glucose. In vitro, human umbilical vein endothelial cells (HUVECs)transfected with miR-17 mimics or inhibitors were incubated with normal-glucose or high-glucose (HG)medium. In vivo, miR-17 or negative control antagomirs were administered by tail vein injection in an MI model of streptozotocin (STZ)-induced diabetic mice. MiR-17 was upregulated, while VEGFA was downregulated in MI mice with diabetes and in HUVECs exposed to HG. The luciferase reporter gene assay confirmed that VEGFA is a target gene of miR-17. Moreover, inhibition of miR-17 prevented HG-induced VEGFA downregulation and impaired the capacity for migration and tube formation in HUVECs. Administration of miR-17 antagomirs significantly improved LV function and reduced infarct size in diabetic post-MI mice. Furthermore, the effects of diabetes-induced decreases in angiogenesis and VEGFA expression were abrogated by miR-17 antagomirs treatment in diabetic infarcted myocardium. These findings suggest that inhibition of miR-17 prevents HG-induced impairment of angiogenesis and improves cardiac function after MI by targeting VEGFA in diabetic mice. © 2019 Elsevier Inc.

Hyperglycaemia is known to impair angiogenesis, which may contribute to the poor prognosis of diabetic patients following myocardial infarction (MI). miR-17 has been reported to be involved in the proliferation, migration, and angiogenesis of a variety of vascular endothelial cells. However, how miR-17 regulates angiogenesis under hyperglycaemic conditions has not been reported. Thus, the aim of this study was to investigate the role of miR-17 in the impairment of angiogenesis induced by high glucose. In vitro, human umbilical vein endothelial cells (HUVECs)transfected with miR-17 mimics or inhibitors were incubated with normal-glucose or high-glucose (HG)medium. In vivo, miR-17 or negative control antagomirs were administered by tail vein injection in an MI model of streptozotocin (STZ)-induced diabetic mice. MiR-17 was upregulated, while VEGFA was downregulated in MI mice with diabetes and in HUVECs exposed to HG. The luciferase reporter gene assay confirmed that VEGFA is a target gene of miR-17. Moreover, inhibition of miR-17 prevented HG-induced VEGFA downregulation and impaired the capacity for migration and tube formation in HUVECs. Administration of miR-17 antagomirs significantly improved LV function and reduced infarct size in diabetic post-MI mice. Furthermore, the effects of diabetes-induced decreases in angiogenesis and VEGFA expression were abrogated by miR-17 antagomirs treatment in diabetic infarcted myocardium. These findings suggest that inhibition of miR-17 prevents HG-induced impairment of angiogenesis and improves cardiac function after MI by targeting VEGFA in diabetic mice. © 2019 Elsevier Inc.

Today, Internet of Things (IoT) technology is being increasingly popular which is applied in a wide range of industry sectors such as healthcare, transportation and some critical infrastructures. With the widespread applications of IoT technology, people's lives have changed dramatically. Due to its capabilities of sensitive data-aware, information collection, communication and processing, it raises security and privacy concerns. Moreover, a malicious attacker may impersonate a legitimate user, which may cause security threat and violation privacy. In allusion to the above problems, we propose a novel and lightweight anonymous authentication and key agreement scheme for heterogeneous IoT, which is innovatively designed to shift between the public key infrastructure (PKI) and certificateless cryptography (CLC) environment. The proposed scheme not only achieves secure communication among the legal authorized users, but also possesses more attributes with user anonymity, non-repudiation and key agreement fairness. Through the security analysis, it is proved that the proposed scheme can resist replay attacks and denial of service (DOS) attacks. Finally, the performance evaluation demonstrates that our scheme is more lightweight and innovative., Comment: 7 pages, 4 figures

As key functional units in neural circuits, different types of neuronal synapses play distinct roles in brain information processing, learning, and memory. Synaptic abnormalities are believed to underlie various neurological and psychiatric disorders. Here, by combining cryo-electron tomography and cryo-correlative light and electron microscopy, we distinguished intact excitatory and inhibitory synapses of cultured hippocampal neurons, and visualized the in situ 3D organization of synaptic organelles and macromolecules in their native state. Quantitative analyses of >100 synaptic tomograms reveal that excitatory synapses contain a mesh-like postsynaptic density (PSD) with thickness ranging from 20 to 50 nm. In contrast, the PSD in inhibitory synapses assumes a thin sheet-like structure ∼12 nm from the postsynaptic membrane. On the presynaptic side, spherical synaptic vesicles (SVs) of 25-60 nm diameter and discus-shaped ellipsoidal SVs of various sizes coexist in both synaptic types, with more ellipsoidal ones in inhibitory synapses. High-resolution tomograms obtained using a Volta phase plate and electron filtering and counting reveal glutamate receptor-like and GABAA receptor-like structures that interact with putative scaffolding and adhesion molecules, reflecting details of receptor anchoring and PSD organization. These results provide an updated view of the ultrastructure of excitatory and inhibitory synapses, and demonstrate the potential of our approach to gain insight into the organizational principles of cellular architecture underlying distinct synaptic functions.SIGNIFICANCE STATEMENT To understand functional properties of neuronal synapses, it is desirable to analyze their structure at molecular resolution. We have developed an integrative approach combining cryo-electron tomography and correlative fluorescence microscopy to visualize 3D ultrastructural features of intact excitatory and inhibitory synapses in their native state. Our approach shows tha

As key functional units in neural circuits, different types of neuronal synapses play distinct roles in brain information processing, learning, and memory. Synaptic abnormalities are believed to underlie various neurological and psychiatric disorders. Here, by combining cryo-electron tomography and cryo-correlative light and electron microscopy, we distinguished intact excitatory and inhibitory synapses of cultured hippocampal neurons, and visualized the in situ 3D organization of synaptic organelles and macromolecules in their native state. Quantitative analyses of >100 synaptic tomograms reveal that excitatory synapses contain a mesh-like postsynaptic density (PSD) with thickness ranging from 20 to 50 nm. In contrast, the PSD in inhibitory synapses assumes a thin sheet-like structure ∼12 nm from the postsynaptic membrane. On the presynaptic side, spherical synaptic vesicles (SVs) of 25-60 nm diameter and discus-shaped ellipsoidal SVs of various sizes coexist in both synaptic types, with more ellipsoidal ones in inhibitory synapses. High-resolution tomograms obtained using a Volta phase plate and electron filtering and counting reveal glutamate receptor-like and GABAA receptor-like structures that interact with putative scaffolding and adhesion molecules, reflecting details of receptor anchoring and PSD organization. These results provide an updated view of the ultrastructure of excitatory and inhibitory synapses, and demonstrate the potential of our approach to gain insight into the organizational principles of cellular architecture underlying distinct synaptic functions.SIGNIFICANCE STATEMENT To understand functional properties of neuronal synapses, it is desirable to analyze their structure at molecular resolution. We have developed an integrative approach combining cryo-electron tomography and correlative fluorescence microscopy to visualize 3D ultrastructural features of intact excitatory and inhibitory synapses in their native state. Our approach shows tha

Along with the development of vehicular sensors and wireless communication technology, Internet of Vehicles (IoV) is emerging that can improve traffic efficiency and provide a comfortable driving environment. However, there is still a challenge how to ensure the survivability of IoV. Fortunately, this goal can be achieved by quickly verifying real-time monitoring data to avoid network failure. Aggregate signature is an efficient approach to realize quick data verification quickly. In this paper, we propose a monitoring data batch verification scheme based on an improved certificateless aggregate signature for IoV, named MDBV. The size of aggregated verification message is remain roughly constant even as the increasing number of vehicles in MDBV. Additionally, MDBV is proved to be secure in the random oracle model assuming the intractability of the computational Diffie-Hellman problem. In consideration of the network survivability and performance, the proposed MDBV can decrease the computation overhead and is more suitable for IoV.

With the emerging of mobile communication technologies, we are entering the fifth generation mobile communication system (5G) era. Various application scenarios will arise in the 5G era to meet the different service requirements. Different 5G network slicings may deploy different public key cryptosystems. The security issues among the heterogeneous systems should be considered. In order to ensure the secure communications between 5G network slicings, in different public cryptosystems, we propose two heterogeneous signcryption schemes which can achieve mutual communications between the Public Key Infrastructure (PKI) and the CertificateLess public key Cryptography (CLC) environment. We prove that our schemes have the INDistinguishability against Adaptive Chosen Ciphertext Attack (IND-CCA2) under the Computational Diffie-Hellman Problem (CDHP) and the Existential UnForgeability against adaptive Chosen Message Attack (EUF-CMA) under the Discrete Logarithm Problem (DLP) in the random oracle model. We also set up two heterogeneous cryptosystems on Raspberry Pi to simulate the interprocess communication between different public key environments. Furthermore, we quantify and analyze the performance of each scheme. Compared with the existing schemes, our schemes have greater efficiency and security.

As a popular application, mobile crowd sensing systems aim at providing more convenient service via the swarm intelligence. With the popularity of sensor-embedded smart phones and intelligent wearable devices, mobile crowd sensing is becoming an efficient way to obtain various types of sensing data from individuals, which will make people's life more convenient. However, mobile crowd sensing systems today are facing a critical challenge, namely the privacy leakage of the sensitive information and valuable data, which can raise grave concerns among the participants. To address this issue, we propose an enhanced secure certificateless privacy-preserving verifiable data authentication scheme for mobile crowd sensing, named EPDA. The proposed scheme provides unconditional anonymous data authentication service for mobile crowd sensing, by deploying an improved certificateless ring signature as the cryptogram essential, in which the big sensing data should be signed by one of legitimate members in a specific group and could be verified without exposing the actual identity of the participant. The formal security proof demonstrates that EPDA is secure against existential forgery under adaptive chosen message and identity attacks in random oracle model. Finally, extensive simulations are conducted. The results show that the proposed EPDA efficiently decreases computational cost and time consumption in the sensing data authentication process.

Along with the miniaturization of various types of sensors, a mass of intelligent terminals are gaining stronger sensing capability, which raises a deeper perception and better prospect of Internet of Things (IoT). With big sensing data, IoT provides lots of convenient services for the monitoring and management of smart cities and people's daily lives. However, there are still many security challenges influencing the further development of IoT, one of which is how to quickly verify the big data obtained from IoT terminals. Aggregate signature is an efficient approach to perform big data authentication. It can effectively reduce the computation and communication overheads. In this paper, utilizing these features, we construct a verifiable data aggregation scheme for Internet of Things, named VDAS, based on an improved certificateless aggregate signature algorithm. In VDAS, the length of the aggregated authentication message is independent of the number of IoT terminals. Then, we prove that VDAS is existentially unforgeable under adaptive chosen message attacks assuming that the computational Diffie-Hellman problem is hard. Additionally, the proposed VDAS achieves a better trade-off on the computation overheads between the resource-constrained IoT terminals and the data center.

Vehicular Ad Hoc Networks (VANETs) are attractive scenarios that can improve the traffic situation and provide convenient services for drivers and passengers via vehicle-to-vehicle (V2V) and vehicle-to-infrastructure (V2I) communication. However, there are still many security challenges in the traffic information transmission, especially in the intense traffic case. For ensuring the privacy of users and traceability of vehicles, we propose a traceable concurrent data anonymous transmission scheme for heterogeneous VANETs. The scheme is based on certificateless aggregate signcryption, so it supports batch verification. Moreover, conditional anonymity is also achieved due to the involving of the pseudo-ID technique. Furthermore, it is a pairing-free scheme for the merit of multi-trapdoor hash functions. As a result, the total computation overhead is greatly reduced.

Internet of Vehicles (IoV) is an intelligent application of IoT in smart transportation, which can make intelligent decisions for passengers. It has drawn extensive attention to improve traffic safety and efficiency and create a more comfortable driving and riding environment. Vehicular cloud computing is a variant of mobile cloud computing, which can process local information quickly. The cooperation of the Internet and vehicular cloud can make the communication more efficient in IoV. In this paper, we mainly focus on the secure communication between vehicles and roadside units. We first propose a new certificateless short signature scheme (CLSS) and prove the unforgeability of it in random oracle model. Then, by combining CLSS and a regional management strategy we design an efficient anonymous mutual quick authentication scheme for IoV. Additionally, the quantitative performance analysis shows that the proposed scheme achieves higher efficiency in terms of interaction between vehicles and roadside units compared with other existing schemes.

In recent years, cloud storage technology has been widely used in many fields such as education, business, medical and more because of its convenience and low cost. With the widespread applications of cloud storage technology, data access control methods become more and more important in cloud-based network. The ciphertext policy attribute-based encryption (CP-ABE) scheme is very suitable for access control of data in cloud storage. However, in many practical scenarios, all attributes of a user cannot be managed by one authority, so many multi-authority CP-ABE schemes have emerged. Moreover, cloud servers are usually semi-trusted, which may leak user information. Aiming at the above problems, we propose a fine-grained access control scheme with versatility for cloud storage based on multi-authority CP-ABE, named vFAC. The proposed vFAC has the features of large universe, no key escrow problem, online/offline mechanism, hidden policy, verifiability and user revocation. Finally, we demonstrate vFAC is static security under the random oracle model. Through the comparison of several existing schemes in terms of features, computational overhead and storage cost, we can draw a conclusion that vFAC is more comprehensive and scalable.

Along with the development of wireless communication technology, a mass of mobile devices are gaining stronger sensing capability, which brings a novel paradigm to light: participatory sensing networks (PSNs). PSNs can greatly reduce the cost of wireless sensor networks, and hence are becoming an efficient way to obtain abundant sensing data from surrounding environment. Therefore, PSNs would lead to significant improvement in various fields, including cognitive communication. However, the large-scale deployment of participatory sensing applications is hindered by the lack of incentive mechanism, security and privacy concerns. It is still an ongoing issue to address all three aspects simultaneously in PSNs. In this paper, we construct an efficient privacy-preserving incentive scheme without trusted third party (TTP) for PSNs to motivate user-participation. This scheme allows each participant to earn credits by contributing data privately. Using blind and partially blind signatures, the proposed scheme is proved to be secure for privacy and incentive. Additionally, the performance evaluation in terms of computation and storage indicates that the proposed scheme has higher efficiency.

III-V semiconductor nanowires have attracted extensive research interests over the past few decades due to their unique geometry and great potential for promoting new functionalities in future electronics, light-emitting diodes and solar cells. However, in order to push this technology beyond the laboratory level, it is essential to combine it with the current Si-based semiconductor industry for affordable production. The synthesis of III-As nanowires relies mostly on the use of Au as seed particle, which as a result of high diffusivity of Au in Si, limits the possibility to integrate III-As nanowires into Si devices.The purpose of this thesis is trying to get a better understanding of which properties might be desirable for a material to act as seed particle to assist nanowire growth.This thesis studies Sn-seeded growth of GaAs, InAs and InGaAs nanowires by MOVPE, and how the growth process can be controlled to tailor the nanowire morphology and crystal phase to some exten. The in-situ formation of Sn particles on various substrates has been investigated. The temperature range and the flow of growth precursors for Sn-seeded nanowire growth differ a lot from nanowire growth from Au seed particles. In contrast to Au-seeded nanowires, Sn-seeded GaAs and InAs nanowires mostly exhibit zincblende crystal phase. Furthermore, a big advantage of using Sn as seed material is the simultaneous incorporation of the particle material into the nanowire during growth, leading to nanowires with high n-type doping profile.

3D packaging using through silicon via (TSV) technology is becoming important in IC packaging industry. The polymer material as insulation material was fabricated by the spin-coating or spray-coating process. And the polymer insulation can relax some of the stress induced and makes the process more convenient compared with CVD. Therefore, it is the most cost effective technology for the wafer level packaging. In this study, some polymer insulation materials with different silanes are investigated comprehensively, including viscosity thixotropic index, adhesion strength, thermogravimetry analysis, differential scanning calorimetry and conformal coating. All the results show that the silane has significant effect on the adhesion strength and conformal coating. The adhesion strength is improved when the silane with nitrogen atom, and the insulation layer can be spin-coated uniformly or most filled vias when the silane with different polarity are used.

In this study, copper flake was synthesized through wet ball milling the copper micro sphere, which was used as the filler of epoxy adhesives. The effect of ball milling time and dispersant on morphology of copper have investigated. The effect of ball milling with oleic acid as dispersant is more homogeneous than alcohol. The longer ball milling time, the higher proportion of Cu flake. When ball milling time comes to 2 hours, the thermal conductivity of copper adhesive filled with as-prepared Cu flake comes to threshold. Moreover, permissible voltage of copper adhesive filled with as-prepared Cu flake is reduced. This research provides an efficient way to synthesis Cu micro flake, which can used as the filler of thermal interface materials with high thermal conductivity for integrated circuit packaging application. © 2017 IEEE.

In this article, conductive nickel patterns were constructed on flexible substrates via selectively electroless deposition method, which including four procedures, namely KH550-modification, Ni2+ adsorption, selective Ni0-seeding and Ni-lines deposition. Herein, we use KH550 as a bridge for the catalyst and the surface of substrates, and Ni0 as catalyst to replace the traditional Pd catalyst. In this way, the conductive circuit can be prepared by adding method on the surface of the flexible substrate and suitable for large-scale production. © 2017 IEEE.

We used a facile method to prepare PdCu hollow nanocubes (HNCs) and nanospheres (HNSs) for electroless copper or nickel deposition by via redox reaction with the sacrificial templates of Cu2O. The electrocatalytic performance of PdCu HNSs is higher than PdCu HNCs through CV and EQCM tests. Also, PdCu HNSs was applied to electroless copper and nickel deposition, and find that the quite low concentration up to 1 mM and 2 mM of PdCu alloy for electroless copper and nickel deposition still has the good catalytic performance, respectively. © 2017 IEEE.

In this paper, we reported thermally conductive insulating phase change materials filled with Al2O3-coated Al powder (PCMs/Al@Al2O3) and investigated the effect of composite PCMs on the thermal conductive performance. Result revealed that the content of Al@Al2O3 combines the advantages of both aluminum and alumina. The PCMs/Al@Al2O3 has a thermal conductivity value of 1.6743 w/mk, which is three times as much as the PCMs/Al2O3, and it shows a better ability to prevent leakage. © 2017 IEEE.

In this work, PdCu bimetallic alloy nanoparticles supported on reduced graphene oxide was prepared by a wet-chemistry approach. Atomic-force microscopy (AFM) and scanning electron microscopy (SEM) were performed to characterize the structures of as-prepared grapheme oxide and PdCu nanoparticle on graphene sheet. The electrochemical activity toward formaldehyde electrooxidation in alkaline condition was tested by cyclic voltammetry (CV), and electrochemical quartz crystal microbalance (EQCM) was used to illustrate the performance of electroless copper plating of as-prepared materials as active catalyst. The results indicated that alloy bimetallic nanoparticles supported on graphene sheets could be used as active agent for electroless copper plating on epoxy board and paper. The as-prepared nanocatalyst was promising for the future development of interconnect technologies in electronic packaging. © 2017 IEEE.

3D packaging using through silicon via (TSV) technology is becoming important in IC packaging industry. The polymer material as insulation material was fabricated by the spin-coating or spray-coating process. And the polymer insulation can relax some of the stress induced and makes the process more convenient compared with CVD. Therefore, it is the most cost effective technology for the wafer level packaging. In this study, some polymer insulation materials with different silanes are investigated comprehensively, including viscosity thixotropic index, adhesion strength, thermogravimetry analysis, differential scanning calorimetry and conformal coating. All the results show that the silane has significant effect on the adhesion strength and conformal coating. The adhesion strength is improved when the silane with nitrogen atom, and the insulation layer can be spin-coated uniformly or most filled vias when the silane with different polarity are used.

In this study, copper flake was synthesized through wet ball milling the copper micro sphere, which was used as the filler of epoxy adhesives. The effect of ball milling time and dispersant on morphology of copper have investigated. The effect of ball milling with oleic acid as dispersant is more homogeneous than alcohol. The longer ball milling time, the higher proportion of Cu flake. When ball milling time comes to 2 hours, the thermal conductivity of copper adhesive filled with as-prepared Cu flake comes to threshold. Moreover, permissible voltage of copper adhesive filled with as-prepared Cu flake is reduced. This research provides an efficient way to synthesis Cu micro flake, which can used as the filler of thermal interface materials with high thermal conductivity for integrated circuit packaging application. © 2017 IEEE.

In this article, conductive nickel patterns were constructed on flexible substrates via selectively electroless deposition method, which including four procedures, namely KH550-modification, Ni2+ adsorption, selective Ni0-seeding and Ni-lines deposition. Herein, we use KH550 as a bridge for the catalyst and the surface of substrates, and Ni0 as catalyst to replace the traditional Pd catalyst. In this way, the conductive circuit can be prepared by adding method on the surface of the flexible substrate and suitable for large-scale production. © 2017 IEEE.

In this paper, we reported thermally conductive insulating phase change materials filled with Al2O3-coated Al powder (PCMs/Al@Al2O3) and investigated the effect of composite PCMs on the thermal conductive performance. Result revealed that the content of Al@Al2O3 combines the advantages of both aluminum and alumina. The PCMs/Al@Al2O3 has a thermal conductivity value of 1.6743 w/mk, which is three times as much as the PCMs/Al2O3, and it shows a better ability to prevent leakage. © 2017 IEEE.

We used a facile method to prepare PdCu hollow nanocubes (HNCs) and nanospheres (HNSs) for electroless copper or nickel deposition by via redox reaction with the sacrificial templates of Cu2O. The electrocatalytic performance of PdCu HNSs is higher than PdCu HNCs through CV and EQCM tests. Also, PdCu HNSs was applied to electroless copper and nickel deposition, and find that the quite low concentration up to 1 mM and 2 mM of PdCu alloy for electroless copper and nickel deposition still has the good catalytic performance, respectively. © 2017 IEEE.

3D packaging using through silicon via (TSV) technology is becoming important in IC packaging industry. The polymer material as insulation material was fabricated by the spin-coating or spray-coating process. And the polymer insulation can relax some of the stress induced and makes the process more convenient compared with CVD. Therefore, it is the most cost effective technology for the wafer level packaging. In this study, some polymer insulation materials with different silanes are investigated comprehensively, including viscosity thixotropic index, adhesion strength, thermogravimetry analysis, differential scanning calorimetry and conformal coating. All the results show that the silane has significant effect on the adhesion strength and conformal coating. The adhesion strength is improved when the silane with nitrogen atom, and the insulation layer can be spin-coated uniformly or most filled vias when the silane with different polarity are used.

In this paper, we reported thermally conductive insulating phase change materials filled with Al2O3-coated Al powder (PCMs/Al@Al2O3) and investigated the effect of composite PCMs on the thermal conductive performance. Result revealed that the content of Al@Al2O3 combines the advantages of both aluminum and alumina. The PCMs/Al@Al2O3 has a thermal conductivity value of 1.6743 w/mk, which is three times as much as the PCMs/Al2O3, and it shows a better ability to prevent leakage. © 2017 IEEE.

In this work, PdCu bimetallic alloy nanoparticles supported on reduced graphene oxide was prepared by a wet-chemistry approach. Atomic-force microscopy (AFM) and scanning electron microscopy (SEM) were performed to characterize the structures of as-prepared grapheme oxide and PdCu nanoparticle on graphene sheet. The electrochemical activity toward formaldehyde electrooxidation in alkaline condition was tested by cyclic voltammetry (CV), and electrochemical quartz crystal microbalance (EQCM) was used to illustrate the performance of electroless copper plating of as-prepared materials as active catalyst. The results indicated that alloy bimetallic nanoparticles supported on graphene sheets could be used as active agent for electroless copper plating on epoxy board and paper. The as-prepared nanocatalyst was promising for the future development of interconnect technologies in electronic packaging. © 2017 IEEE.

We used a facile method to prepare PdCu hollow nanocubes (HNCs) and nanospheres (HNSs) for electroless copper or nickel deposition by via redox reaction with the sacrificial templates of Cu2O. The electrocatalytic performance of PdCu HNSs is higher than PdCu HNCs through CV and EQCM tests. Also, PdCu HNSs was applied to electroless copper and nickel deposition, and find that the quite low concentration up to 1 mM and 2 mM of PdCu alloy for electroless copper and nickel deposition still has the good catalytic performance, respectively. © 2017 IEEE.

In this study, copper flake was synthesized through wet ball milling the copper micro sphere, which was used as the filler of epoxy adhesives. The effect of ball milling time and dispersant on morphology of copper have investigated. The effect of ball milling with oleic acid as dispersant is more homogeneous than alcohol. The longer ball milling time, the higher proportion of Cu flake. When ball milling time comes to 2 hours, the thermal conductivity of copper adhesive filled with as-prepared Cu flake comes to threshold. Moreover, permissible voltage of copper adhesive filled with as-prepared Cu flake is reduced. This research provides an efficient way to synthesis Cu micro flake, which can used as the filler of thermal interface materials with high thermal conductivity for integrated circuit packaging application. © 2017 IEEE.

In this article, conductive nickel patterns were constructed on flexible substrates via selectively electroless deposition method, which including four procedures, namely KH550-modification, Ni2+ adsorption, selective Ni0-seeding and Ni-lines deposition. Herein, we use KH550 as a bridge for the catalyst and the surface of substrates, and Ni0 as catalyst to replace the traditional Pd catalyst. In this way, the conductive circuit can be prepared by adding method on the surface of the flexible substrate and suitable for large-scale production. © 2017 IEEE.

Electroplating is used here to fabricate a SnAgCu eutectic solders coating on copper substrate. The optimized coating is composed of Sn, Ag and Cu with the weight ratio of 96.4:3.0:0.6. Its melting temperature was confirmed at 215-220 °C. The coating thickness was controlled at 10 μm and its thermal conductivity reaches up to 56.7 W/mK.

Uniform NiO mesoporous nanowalls are easily fabricated on reduced graphene oxide (RGO) nanosheets coated three dimensional nickel foams (3D NF-G) through a simple aqueous deposition with successive annealing. The structure and morphology of the resulting NiO nanowalls supported on 3D NF-G composites (3D NF-G-NiO) are characterized by scanning electron microscopy (SEM), transmission electron microscopy (TEM), X-ray diffraction (XRD) and energy-dispersive X-ray spectroscopy (EDX). The 3D NF-G-NiO composites are directly used as binder-free electrodes for supercapacitors and biosensors. For supercapacitor, the electrode delivers high specific capacitance of about 950 F g-1 at a current density of 5 A g-1 with excellent cycling stability. As glucose sensor, the 3D NF-G-NiO electrode can detect glucose with an ultrahigh sensitivity of 3.23 mAmM-1 cm-2 and a superior selectivity with a remarkable lower detection limit towards 10 μM. © 2016 Elsevier Ltd. All rights reserved.

Al2O3 coated graphene foam (GF@Al2O3) composites are proposed by depositing insulating Al2O3 particles on the graphene with a simple method. The content of Al2O3 on graphene could be gradually adjusted by changing Al(OH)3 radio in solution. Al2O3 coated graphene foam composites are used as effective three dimension (3D) interconnected framework of paraffin phase change materials to increase thermal conductive and high electrical resistance. The GF@Al2O3 provides enormous thermal conductive pathways for heat transfer, suitable for application as thermal interface materials (TIMs). © 2016 IEEE.

Dendrite-like Cu supported Pd catalysts were prepared for electroless deposition of Cu circuits. The as-preapred catalysts demonstrated excellent catalytic activity. © 2016 IEEE.

A novel organosilane precursor, (hexfluoropropane-2, 2-diyl)dibenzyl-bridged organosilane (HFPDBO) precursor, was prepared by a simple and facile synthesis. There are some superiorities designed in HFPDBO precursor, for instance, hexfluoro-substitutions and dibenzene can contribute to higher porosity and lower dielectric constant, rigid carbon bridged construction and tetrafunctional organosilane branches are beneficial to promoting polymerization and mechanical properties. Purified HFPDBO precursor were mixed with porogen Brij® L4, acid and ethanol for coating solution, and the HFPDBO-based PMO thin film was prepared via evaporation-induced self-assembly (EISA) method. The novel PMO thin film emerges excellent dielectric property (dielectric constants of 1.58@1 MHz) and high mechanical property (Young's modulus of 5.54±0.11 GPa), besides it shows order structure and hydrophobic property.

Through silicon via (TSV) is an enabling technology for 3D interconnection. The insulation layer at the bottom of the via usually needs to be removed in order to expose the pad so that the electrical interconnection from the front side to the back side can be realized. This removal may be implemented by plasma etching, laser drilling, or photo-lithography. Compared with the other two methods, photo-lithography is considered having the merits of high efficiency, high reliability and low cost. In this study, we developed a photosensitive polymer insulation material that can be deposited with the spin-coating process. The photosensitive material at the bottom of the TSV was developed with potassium hydroxide (KOH) solution after exposure to thr 365 nm UV light. At last, the residual photosensitive polymer was cured via a preset heating procedure. The resulting polymer insulation layer exhibited excellent thermal stability, good chemical resistance, good adhesion and good thickness uniformity. Such a material may be considered a promising candidate for the insulation layer for the applications of CMOS image sensor (CIS) and fingerprint identification sensor with TSVs having a low aspect ratio.

A low-dielectric-constant organosilica was developed for interlayer dielectric, introducing adamantane which possesses low polarity and unique rigid structure. Novel organosilane precursor, adamantane-bridged organosilane precursor, was synthesized and characterized. Precursor was mixed with porogen P123, acid and ethanol to prepare coating solution, and the novel periodic mesoporous organosilica (PMO) thin film was prepared via evaporation-induced self-Assembly method. The PMO thin film presents ultra-low dielectric constants (1.56@1 MHz) and high Young's modulus (6.69±0.54 GPa) via optimizing the porogen content, besides it shows order structure and hydrophobic property.

A binder-free flexible graphene-SnO2 film electrode is readily obtained through filtration of electrochemically exfoliated graphene in Na2SnO3 electrolyte solution. Compared to the traditional polymer binder and carbon black formed electrode with the thermal conductivity usually lower than 2 W m-1 K-1, the binder-free graphene-SnO2 film electrode exhibits a greatly higher thermal conductivity of 535.3 W m-1 K-1, which is beneficial to heat dissipation for lithium ion batteries. The graphene-SnO2 film anode electrode also demonstrates a high capacity of 698.8 mA h g-1 at a current density of 200 mA g-1 even after 100 charge-discharge cycles. © 2016 The Royal Society of Chemistry.

Graphene foam (GF), carbon fibers (CFs) and GF/CFs reinforced epoxy resin composites were fabricated and their thermal properties were investigated. Due to continuous interconnected structures of GF and avoiding the CFs aggregation in epoxy resin, GF/CFs reinforced epoxy resin demonstrates greatly higher thermal conductivity than the single GF or CFs reinforced epoxy, which could provide a strong candidate for highly thermal conductive polymer composites. © 2016 IEEE.

Low melting alloy is mixed with Cu filler as thermal interface materials. The thermal performance is investigated by inserting the composite between Al blocks. The ratio of Cu filler is optimized to be 50% to achieve the lowest thermal resistance.