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Due to long-term reliability, wireless control systems (WCSs) have attracted significant interest recently. However, mission-critical control requires stringent ultra-reliability and low-latency communication (URLLC) with massive data delivery, which are major challenges for conventional wireless networks. This paper investigates downlink URLLC in WCS, where the semantic communication is adopted at the control center to extract task-oriented semantic information from original large-sized data. To efficiency, the control center utilizes the rate splitting policy to deliver semantic information through private messages, while the semantic knowledge is transmitted through one common message. We aim to maximize the weighted sum semantic information transmission rate by jointly optimizing the semantic information extraction, delivery duration, rate splitting, and transmit beamforming, subject to several practical constraints, including recovery accuracy, quality of service requirements, communication latency and computation delay. By the problem decomposition, two sub-problems are obtained, where the closed-form solution for the semantic information extraction is derived at each step. Due to the complexity of the multivariable coupling in the channel dispersion, we propose fractional transformation methods for rate splitting design. Numerical results confirm that the RSMA and semantic communication design can complement each other for multiplexing gains enhancement and latency reduction to achieve overloaded connections., QC 20240402

In this paper, channel estimation problem for extremely large-scale multi-input multi-output (XL-MIMO) systems is investigated with the considerations of the spherical wavefront effect and the spatially non-stationary (SnS) property. Due to the diversities of SnS characteristics among different propagation paths, the concurrent channel estimation of multiple paths becomes intractable. To address this challenge, we propose a two-phase channel estimation scheme. In the first phase, the angles of departure (AoDs) on the user side are estimated, and a carefully designed pilot transmission scheme enables the decomposition of the received signal from different paths. In the second phase, the subchannel estimation corresponding to different paths is formulated as a three-layer Bayesian inference problem. Specifically, the first layer captures block sparsity in the angular domain, the second layer promotes SnS property in the antenna domain, and the third layer decouples the subchannels from the observed signals. To efficiently facilitate Bayesian inference, we propose a novel three-layer generalized approximate message passing (TL-GAMP) algorithm based on structured variational massage passing and belief propagation rules. Simulation results validate the convergence and effectiveness of the proposed algorithm, showcasing its robustness to different channel scenarios., Comment: This manuscript has been submitted to the IEEE journal for possible pubilcation

The transformation from one compound to another involves the breaking and formation of chemical bonds at the single-bond level, especially during catalytic reactions that are of great significance in broad fields such as energy conversion, environmental science, life science and chemical synthesis. The study of the reaction process at the single-bond limit is the key to understanding the catalytic reaction mechanism and further rationally designing catalysts. Here, we develop a method to monitor the catalytic process from the perspective of the single-bond energy using high-resolution scanning tunneling microscopy single-molecule junctions. Experimental and theoretical studies consistently reveal that the attack of a halogen atom on an Au atom can reduce the breaking energy of Au−S bonds, thereby accelerating the bond cleavage reaction and shortening the plateau length during the single-molecule junction breaking. Furthermore, the distinction in catalytic activity between different halogen atoms can be compared as well. This study establishes the intrinsic relationship among the reaction activation energy, the chemical bond breaking energy and the single-molecule junction breaking process, strengthening our mastery of catalytic reactions towards precise chemistry.

Extremely Large-scale Array (ELAA) promises to deliver ultra-high data rates with increased antenna elements. However, increasing antenna elements leads to a wider realm of near-field, which challenges the traditional design of codebooks. In this paper, we propose novel near-field codebook schemes based on the fitting formula of codewords' quantization performance. First, we analyze the quantization performance properties of uniform linear array (ULA) and uniform planar array (UPA) codewords. Our findings reveal an intriguing property: the correlation formula for ULA codewords can be represented by the elliptic formula, while the correlation formula for UPA codewords can be approximated using the ellipsoid formula. Building on this insight, we propose a ULA uniform codebook that maximizes the minimum correlation based on the derived formula. Moreover, we introduce a ULA dislocation codebook to further reduce quantization overhead. Continuing our exploration, we propose UPA uniform and dislocation codebook schemes. Our investigation demonstrates that oversampling in the angular domain offers distinct advantages, achieving heightened accuracy while minimizing overhead in quantifying near-field channels. Numerical results demonstrate the appealing advantages of the proposed codebook over existing methods in decreasing quantization overhead and increasing quantization accuracy.

Intelligent reflecting surface (IRS) has been considered as a revolutionary technology to enhance the wireless communication performance. To cater for multiple mobile users, adjusting IRS beamforming patterns over time, i.e., dynamic IRS beamforming (DIBF), is generally needed for achieving satisfactory performance, which results in high controlling power consumption and overhead. To avoid such cost, we propose a new architecture based on the static regulated IRS for wireless coverage enhancement, where the principle of distributed multiple-input multiple-output (D-MIMO) is integrated into the system to exploite the diversity of spatial directions provided by multiple access points (APs). For this new D-MIMO empowered static IRS architecture, the total target area is partitioned into several subareas and each subarea is served by an assigned AP. We consider to maximize the worst-case received power over all locations in the target area by jointly optimizing a single set of IRS beamforming pattern and AP-subarea association. Then, a two-step algorithm is proposed to obtain its high-quality solution. Theoretical analysis unveils that the fundamental squared power gain can still be achieved over all locations in the target area. The performance gap relative to the DIBF scheme is also analytically quantified. Numerical results validate our theoretical findings and demonstrate the effectiveness of our proposed design over benchmark schemes., Comment: Submitted to IEEE WCL for possible publication

Reconfigurable intelligent surface (RIS) is a new technique that is able to manipulate the wireless environment smartly and has been exploited for assisting the wireless communications, especially at high frequency band. However, it suffers from hardware impairments (HWIs) in practical designs, which inevitably degrades its performance and thus limits its full potential. To address this practical issue, we first propose a new RIS reflection model involving phase-shift errors, which is then verified by the measurement results from field trials. With this beamforming model, various phase-shift errors caused by different HWIs can be analyzed. The phase-shift errors are classified into three categories: (1) globally independent and identically distributed errors, (2) grouped independent and identically distributed errors and (3) grouped fixed errors. The impact of typical HWIs, including frequency mismatch, PIN diode failures and panel deformation, on RIS beamforming ability are studied with the theoretical model and are compared with numerical results. The impact of frequency mismatch are discussed separately for narrow-band and wide-band beamforming. Finally, useful insights and guidelines on the RIS design and its deployment are highlighted for practical wireless systems.

Ruipeng Zhong,1,2,* Yun Zou,3,* ShuZhen Bao,2 YiJian Chen,2 Guiming Huang,2 Lifeng Wang,3 Li Chen,3 Maolin Zhong,3 Weidong Liang3 1Gannan Medical University, Ganzhou, People’s Republic of China; 2Department of Anesthesiology,Ganzhou People’s Hospital, Ganzhou, People’s Republic of China; 3Anesthesia Surgery Center, the First Affiliated Hospital of Gannan Medical University, Ganzhou, People’s Republic of China*These authors contributed equally to this workCorrespondence: Weidong Liang, Anesthesia Surgery Center, the First Affiliated Hospital of Gannan Medical University, No. 128, Jinling West Road, Economic and Technological Development Zone, Ganzhou, Jiangxi Province, 341000, People’s Republic of China, Tel +86 15970122157, Email lwd0929@gmu.edu.cnPurpose: This study aimed to investigate the analgesic effect of ultrasound-guided transversus thoracis plane block (TTPB) combined with intermediate cervical plexus block (ICPB) in the early postoperative period after trans-areolar endoscopic thyroidectomy.Patients and Methods: A total of 62 female patients undergoing trans-areolar endoscopic thyroidectomy were randomly classified to the TTPB combined with ICPB group with ropivacaine (block group) or superficial cervical plexus block group (control group). The primary outcome measures were resting visual analogue scale (VAS) in the chest area at 6 h after surgery. The secondary outcome measures included chest resting and movement VAS score, neck resting and movement VAS score within 24 h after surgery, intraoperative remifentanil consumption, postoperative analgesia rate and analgesic requirements and patient satisfaction score for pain management at discharge.Results: Compared with the control group, the block group at rest showed consistently lower VAS scores in the chest area at 6 and 12 h after operation; the block group at rest showed lower VAS scores in the neck at 6, 12 and 24 h after operation. Regarding movement, the VAS scores o

The extremely large-scale massive multiple-input multiple-output (XL-MIMO) has the potential to achieve boosted spectral efficiency and refined spatial resolution for future wireless networks. However, channel estimation for XL-MIMO is challenging since the large number of antennas results in high computational complexity with the near-field effect. In this letter, we propose a low-complexity sequential angle-distance channel estimation (SADCE) method for near-field XL-MIMO systems equipped with uniformly planar arrays (UPA). Specifically, we first successfully decouple the angle and distance parameters, which allows us to devise a two-dimensional discrete Fourier transform (2D-DFT) method for angle parameters estimation. Then, a low-complexity distance estimation method is proposed with a closed-form solution. Compared with existing methods, the proposed method achieves significant performance gain with noticeably reduced computational complexity.Numerical results verify the superiority of the proposed near-field channel estimation algorithm.

In this work, we investigate the joint visibility region (VR) detection and channel estimation (CE) problem for extremely large-scale multiple-input-multiple-output (XL-MIMO) systems considering both the spherical wavefront effect and spatial non-stationary (SnS) property. Unlike existing SnS CE methods that rely on the statistical characteristics of channels in the spatial or delay domain, we propose an approach that simultaneously exploits the antenna-domain spatial correlation and the wavenumber-domain sparsity of SnS channels. To this end, we introduce a two-stage VR detection and CE scheme. In the first stage, the belief regarding the visibility of antennas is obtained through a VR detection-oriented message passing (VRDO-MP) scheme, which fully exploits the spatial correlation among adjacent antenna elements. In the second stage, leveraging the VR information and wavenumber-domain sparsity, we accurately estimate the SnS channel employing the belief-based orthogonal matching pursuit (BB-OMP) method. Simulations show that the proposed algorithms lead to a significant enhancement in VR detection and CE accuracy as compared to existing methods, especially in low signal-to-noise ratio (SNR) scenarios., Comment: A major revision version has been submitted to IEEE journal

Distributed machine learning (DML) over time-varying networks can be an enabler for emerging decentralized ML applications such as autonomous driving and drone fleeting. However, the commonly used weighted arithmetic mean model aggregation function in existing DML systems can result in high model loss, low model accuracy, and slow convergence speed over time-varying networks. To address this issue, in this paper, we propose a novel non-linear class of model aggregation functions to achieve efficient DML over time-varying networks. Instead of taking a linear aggregation of neighboring models as most existing studies do, our mechanism uses a nonlinear aggregation, a weighted power-p mean (WPM), as the aggregation function of local models from neighbors. The subsequent optimizing steps are taken using mirror descent defined by a Bregman divergence that maintains convergence to optimality. In this paper, we analyze properties of the WPM and rigorously prove convergence properties of our aggregation mechanism. Additionally, through extensive experiments, we show that when p > 1, our design significantly improves the convergence speed of the model and the scalability of DML under time-varying networks compared with arithmetic mean aggregation functions, with little additional computation overhead., Comment: 13 pages, 26 figures

Cell-free massive MIMO provides ubiquitous connectivity for multiple users, and implementation using radio stripes is very efficient. This paper proposes a parallel scheme for radio stripes to allow access point to do signal processing simultaneously. Simple maximum ratio (MR) processing works in this scheme, but its performance is bad. Therefore, this paper further proposes two efficient parallel schemes to gain better performance. The first is interference-aware MR processing with a tailored user-centric strategy. The second is distributed regularized zero-forcing (D-RZF) algorithm which derives from LMMSE. Simulation results show that the proposed parallel schemes gain better performance than existing works.

Guanzhong narrow courtyard is a traditional architecture form of family house in Guanzhong area in China. This project will be dedicated to my grandmother. She used to live in such house for decades. Although she has moved to city long ago, she is still missing the life in such narrow courtyard house. Unfortunately the old house has been teared down just like most of them in Guanzhong area. So I would like to design a new house for her and explore a way to translate the traditional architecture form into a modern building.

Guanzhong narrow courtyard is a traditional architecture form of family house in Guanzhong area in China. This project will be dedicated to my grandmother. She used to live in such house for decades. Although she has moved to city long ago, she is still missing the life in such narrow courtyard house. Unfortunately the old house has been teared down just like most of them in Guanzhong area. So I would like to design a new house for her and explore a way to translate the traditional architecture form into a modern building.

Yijian Chen,1,2,* Demei Zhu,1,2,* Yingyuan Zhang,1,2 Yongjie Zhao,3 Gang Chen,4 Ping Li,5 Lihong Xu,6 Ping Yan,6 M Anne Hickman,7 Xiajun Xu,6 Margaret Tawadrous,7 Michele Wible7 1Institute of Antibiotics, Huashan Hospital Fudan University, Shanghai, China; 2Key Laboratory of Clinical Pharmacology of Antibiotics, National Health and Family Planning Commission, Shanghai, China; 3Department of General Surgery, Tianjin Union Medical Center, Tianjin, China; 4Department of Hepatobiliary Surgery, First People’s Hospital of Kunming, Kunming, China; 5Department of General Surgery, Sichuan Provincial People’s Hospital, Chengdu, China; 6Pfizer (China) Research & Development Co, Ltd, Shanghai, China; 7Pfizer Inc., Collegeville, PA, USA *These authors contributed equally to this work Purpose: To assess the efficacy and safety of tigecycline in treating complicated intra-abdominal infections (cIAIs) in hospitalized patients in China. Patients and methods: A Phase IV, multicenter, randomized, double-blinded, active-controlled, non-inferiority study was conducted. Hospitalized cIAI patients ≥18 years of age were randomized (1:1) to receive intravenous tigecycline (initial dose 100 mg, then 50 mg q12h) or imipenem/cilastatin (500 mg/500 mg or adjusted for renal dysfunction, q6h) for 5–14 days. The primary end point was clinical response for clinically evaluable (CE) subjects at test-of-cure (TOC) assessment. Results: Four hundred and seventy subjects were randomized; 232 in the tigecycline and 231 in the imipenem/cilastatin group were treated. Tigecycline was non-inferior to imipenem/cilastatin with respect to clinical response at TOC for all CE subjects, ie, the lower bound of the two-sided 95% CI (−12.0%, −1.4%) for the treatment difference in cure rate, tigecycline (89.9%) minus imipenem/cilastatin (96.6%), was >−15%. As non-inferiority was concluded in the CE population, superiority of tigecycline

The use of rod-like and vesicle-like mesoporous SiO(2) particles for fabricating high performance glucose biosensors is reported. The distinctively high surface areas of mesoporous structures of SiO(2) rendered the adsorption of glucose oxidase (GOx) feasible. Both morphologies of SiO(2) enhanced the sensitivities of glucose biosensors, but by a factor of 36 for vesicle-like SiO(2) and 18 for rod-like SiO(2), respectively. The greater enhancement of vesicle-like SiO(2) can be accounted for by its higher specific surface area (509 m(2) g(-1)) and larger total pore volume (1.49 cm(3) g-1). Interestingly, the current responses of GOx immobilized in interior channels of the mesoporous SiO(2) were enhanced much more than those of simple mixtures of GOx and the mesoporous SiO(2). This suggests that the enhancement of current responses arise not only from the high surface area of SiO(2) for high enzyme loading, but also from the improved enzyme activity upon its adsorption on mesoporous SiO(2). Also compared were the performances of glucose biosensors with GOx immobilized on mesoporous SiO(2) by physical adsorption and by covalent binding to 3-aminopropyltrimethoxysilane (APTMS) modified SiO(2) using glutaraldehyde as the crosslinker. The covalent binding approach resulted in higher enzyme loading but lower current sensitivity than with the physical adsorption. (C) 2011 Elsevier B.V. All rights reserved.

The use of rod-like and vesicle-like mesoporous SiO(2) particles for fabricating high performance glucose biosensors is reported. The distinctively high surface areas of mesoporous structures of SiO(2) rendered the adsorption of glucose oxidase (GOx) feasible. Both morphologies of SiO(2) enhanced the sensitivities of glucose biosensors, but by a factor of 36 for vesicle-like SiO(2) and 18 for rod-like SiO(2), respectively. The greater enhancement of vesicle-like SiO(2) can be accounted for by its higher specific surface area (509 m(2) g(-1)) and larger total pore volume (1.49 cm(3) g-1). Interestingly, the current responses of GOx immobilized in interior channels of the mesoporous SiO(2) were enhanced much more than those of simple mixtures of GOx and the mesoporous SiO(2). This suggests that the enhancement of current responses arise not only from the high surface area of SiO(2) for high enzyme loading, but also from the improved enzyme activity upon its adsorption on mesoporous SiO(2). Also compared were the performances of glucose biosensors with GOx immobilized on mesoporous SiO(2) by physical adsorption and by covalent binding to 3-aminopropyltrimethoxysilane (APTMS) modified SiO(2) using glutaraldehyde as the crosslinker. The covalent binding approach resulted in higher enzyme loading but lower current sensitivity than with the physical adsorption. (C) 2011 Elsevier B.V. All rights reserved.

The Langmuir monolayer is widely regarded as a model for investigating biomineralization on biological membranes, but so far the crystallization process has been elusive. In this work, we study the crystallization process of CaCO3 on a stearic acid monolayer at the air-water interface by in situ Brewster angle microscopy and ex situ electron microscopy. It is shown that the final CaCO3 crystals are transformed from a particle precursor rather than directly from the solvated ions under the compressed stearic acid monolayer. SEM and TEM images reveal that the precursors are uniform spherical particles of amorphous calcium carbonate (ACC) with sizes smaller than 100 nm. The amorphous particles are produced in an early stage of mineralization and can be stabilized for at least 0.5 h. Subsequently, the ACC particles tend to aggregate with increasing population and are eventually transformed into the crystalline calcite phase with the elapse of time. This work is the first to clarify the crystallization process of calcium carbonate under the monolayer at the air-water interface by a direct observation of the ACC and therefore establish the roles of stearic acid in the process.

A lipase from Candida rugosa (CRL) has been immobilized in mesoporous rod-like silica and vesicle-like (or onion-like) silica supports by physical adsorption. The mesostructures and characteristics of the two mesoporous materials before and after adsorption of CRL were characterized by HRTEM, FESEM, SAXRD and N-2 adsorption-desorption experiments. The pore sizes of the rod-like silica and the vesicle-like silicas were determined to be ca. 11 and 12 nm, respectively, larger than enough to accommodate lipase and 12 nm, respectively, larger than enough to accommodate lipase molecules (similar to 4 nm). The structural integrity of the rod-like silica as well as the vesicle-like silica is retained after adsorption of CRL into the mesopores. The catalytic activity, thermostability, and operational stability of the immobilized CRL were measured in phosphate buffer solution by hydrolysis of tributyrin, When the lipase immobilized in the vesicle-like silica was used as biocatalyst for hydrolysis of tributyrin in a batch process, the hydrolysis activity decreased only slightly from 74\% to 60\% over 10 cycles of reuse, indicating no obvious leaching out of the lipase from the round channels. The activity of vesicle-like silica immobilized CRL for catalytic hydrolysis of tributyrin is 21\% and 14\% higher than that of rod-like silica immobilized CRL at incubation temperature of 60 degrees C at 30 min and 90 min, respectively. The results demonstrate that the lipase immobilized in vesicle-like silica is superior to the rod-like silica in terms of higher activity, reusability and thermal stability. The unique curvature and the large size of the interlamellar pores of vesicle-like silica are suggested to be possible factors in achieving the higher activity and stability. Such a distinctive mesoporous geometry of the vesicle-like silica promises technological applications in protein adsorption and catalysis. (C) 2008 Elsevier Inc. All rights reserved.

The Langmuir monolayer is widely regarded as a model for investigating biomineralization on biological membranes, but so far the crystallization process has been elusive. In this work, we study the crystallization process of CaCO3 on a stearic acid monolayer at the air-water interface by in situ Brewster angle microscopy and ex situ electron microscopy. It is shown that the final CaCO3 crystals are transformed from a particle precursor rather than directly from the solvated ions under the compressed stearic acid monolayer. SEM and TEM images reveal that the precursors are uniform spherical particles of amorphous calcium carbonate (ACC) with sizes smaller than 100 nm. The amorphous particles are produced in an early stage of mineralization and can be stabilized for at least 0.5 h. Subsequently, the ACC particles tend to aggregate with increasing population and are eventually transformed into the crystalline calcite phase with the elapse of time. This work is the first to clarify the crystallization process of calcium carbonate under the monolayer at the air-water interface by a direct observation of the ACC and therefore establish the roles of stearic acid in the process.

The Langmuir monolayer is widely regarded as a model for investigating biomineralization on biological membranes, but so far the crystallization process has been elusive. In this work, we study the crystallization process of CaCO3 on a stearic acid monolayer at the air-water interface by in situ Brewster angle microscopy and ex situ electron microscopy. It is shown that the final CaCO3 crystals are transformed from a particle precursor rather than directly from the solvated ions under the compressed stearic acid monolayer. SEM and TEM images reveal that the precursors are uniform spherical particles of amorphous calcium carbonate (ACC) with sizes smaller than 100 nm. The amorphous particles are produced in an early stage of mineralization and can be stabilized for at least 0.5 h. Subsequently, the ACC particles tend to aggregate with increasing population and are eventually transformed into the crystalline calcite phase with the elapse of time. This work is the first to clarify the crystallization process of calcium carbonate under the monolayer at the air-water interface by a direct observation of the ACC and therefore establish the roles of stearic acid in the process.

A lipase from Candida rugosa (CRL) has been immobilized in mesoporous rod-like silica and vesicle-like (or onion-like) silica supports by physical adsorption. The mesostructures and characteristics of the two mesoporous materials before and after adsorption of CRL were characterized by HRTEM, FESEM, SAXRD and N-2 adsorption-desorption experiments. The pore sizes of the rod-like silica and the vesicle-like silicas were determined to be ca. 11 and 12 nm, respectively, larger than enough to accommodate lipase and 12 nm, respectively, larger than enough to accommodate lipase molecules (similar to 4 nm). The structural integrity of the rod-like silica as well as the vesicle-like silica is retained after adsorption of CRL into the mesopores. The catalytic activity, thermostability, and operational stability of the immobilized CRL were measured in phosphate buffer solution by hydrolysis of tributyrin, When the lipase immobilized in the vesicle-like silica was used as biocatalyst for hydrolysis of tributyrin in a batch process, the hydrolysis activity decreased only slightly from 74\% to 60\% over 10 cycles of reuse, indicating no obvious leaching out of the lipase from the round channels. The activity of vesicle-like silica immobilized CRL for catalytic hydrolysis of tributyrin is 21\% and 14\% higher than that of rod-like silica immobilized CRL at incubation temperature of 60 degrees C at 30 min and 90 min, respectively. The results demonstrate that the lipase immobilized in vesicle-like silica is superior to the rod-like silica in terms of higher activity, reusability and thermal stability. The unique curvature and the large size of the interlamellar pores of vesicle-like silica are suggested to be possible factors in achieving the higher activity and stability. Such a distinctive mesoporous geometry of the vesicle-like silica promises technological applications in protein adsorption and catalysis. (C) 2008 Elsevier Inc. All rights reserved.

In this work, two-photon-excited photoluminescence dynamics in ZnS functionalized ZnO nanotetrapods were investigated. Comparing to the bare ZnO nanotetrapods, the emission peaks of the ZnO/ZnS nanotetrapods red-shifted by 5-10 nm, and the photoluminescence intensity and lifetime of the ultraviolet exciton radiative transition increased more than 20 times due to the passivation effect of the core/shell structure. (C) 2008 Elsevier B.V. All rights reserved.

In this work, two-photon-excited photoluminescence dynamics in ZnS functionalized ZnO nanotetrapods were investigated. Comparing to the bare ZnO nanotetrapods, the emission peaks of the ZnO/ZnS nanotetrapods red-shifted by 5-10 nm, and the photoluminescence intensity and lifetime of the ultraviolet exciton radiative transition increased more than 20 times due to the passivation effect of the core/shell structure. (C) 2008 Elsevier B.V. All rights reserved.

In this work, two-photon-excited photoluminescence dynamics in ZnS functionalized ZnO nanotetrapods were investigated. Comparing to the bare ZnO nanotetrapods, the emission peaks of the ZnO/ZnS nanotetrapods red-shifted by 5-10 nm, and the photoluminescence intensity and lifetime of the ultraviolet exciton radiative transition increased more than 20 times due to the passivation effect of the core/shell structure. (C) 2008 Elsevier B.V. All rights reserved.

Protein adsorption on poly(ethylene oxide) (PEO) and oligo(ethylene oxide) (OEO) monolayers is studied at different packing densities using the Langmuir technique. In the case of a PEO monolayer, a protein adsorption minimum is revealed at sigma(-1) = 10 nm(2) for both lysozyme and fibrinogen. Manifested are two packing density regimes of steric repulsion and compressive attraction between PEO and a protein on top of the overall attraction of the protein to the air/water interface. The observed protein adsorption minimum coincides with the maximum of the surface segment density at sigma(-1) = 10 nm(2). However, OEO monolayer presents a different scenario, namely that the amount of protein adsorbed decreases monotonically with increasing packing density, indicating that the OEO chains merely act as a steric barrier to protein adsorption onto the air/water interface. Besides, in the adsorption of fibrinogen, three distinct kinetic regimes controlled by diffusion, penetration and rearrangement are recognized, whereas only the latter two were made out in the adsorption of lysozyme.

Highly regular vesicle- like silica consisting of concentric shells of silica and voids in alternation have been prepared in a multilamellar vesicles (MLVs) template created with a P123 surfactant and a hydrophobic additive 1,3,5- triisopropylbenzene (TIPB) by hydrolysis and condensation of tetraethoxysilane (TEOS). It is shown that the morphology of the mesoporous silica is mainly controlled by the molar ratio of TIPB : P123. Cylindrical- channel (rod-like) mesoporous silica with hexagonal structure was obtained at low molar ratio of TIPB : P123, while a vesicle-like mesoporous silica was prepared at high molar ratio of TIPB : P123. TIPB at low concentration was merely dissolved into the hydrophobic core of the P123 cylindrical micelle, but it was forced to spread into the palisade layer at high concentration and ultimately transformed the cylindrical micelle phase into the MLV phase. The key role of TIPB has been demonstrated in increasing the average packing parameter (P) of P123, and this opens the way to synthesize vesicle-like silica simply by controlling the molar ratio of TIPB : P123.

Protein adsorption on poly(ethylene oxide) (PEO) and oligo(ethylene oxide) (OEO) monolayers is studied at different packing densities using the Langmuir technique. In the case of a PEO monolayer, a protein adsorption minimum is revealed at sigma(-1) = 10 nm(2) for both lysozyme and fibrinogen. Manifested are two packing density regimes of steric repulsion and compressive attraction between PEO and a protein on top of the overall attraction of the protein to the air/water interface. The observed protein adsorption minimum coincides with the maximum of the surface segment density at sigma(-1) = 10 nm(2). However, OEO monolayer presents a different scenario, namely that the amount of protein adsorbed decreases monotonically with increasing packing density, indicating that the OEO chains merely act as a steric barrier to protein adsorption onto the air/water interface. Besides, in the adsorption of fibrinogen, three distinct kinetic regimes controlled by diffusion, penetration and rearrangement are recognized, whereas only the latter two were made out in the adsorption of lysozyme.

Protein adsorption on poly(ethylene oxide) (PEO) and oligo(ethylene oxide) (OEO) monolayers is studied at different packing densities using the Langmuir technique. In the case of a PEO monolayer, a protein adsorption minimum is revealed at sigma(-1) = 10 nm(2) for both lysozyme and fibrinogen. Manifested are two packing density regimes of steric repulsion and compressive attraction between PEO and a protein on top of the overall attraction of the protein to the air/water interface. The observed protein adsorption minimum coincides with the maximum of the surface segment density at sigma(-1) = 10 nm(2). However, OEO monolayer presents a different scenario, namely that the amount of protein adsorbed decreases monotonically with increasing packing density, indicating that the OEO chains merely act as a steric barrier to protein adsorption onto the air/water interface. Besides, in the adsorption of fibrinogen, three distinct kinetic regimes controlled by diffusion, penetration and rearrangement are recognized, whereas only the latter two were made out in the adsorption of lysozyme.

Highly regular vesicle- like silica consisting of concentric shells of silica and voids in alternation have been prepared in a multilamellar vesicles (MLVs) template created with a P123 surfactant and a hydrophobic additive 1,3,5- triisopropylbenzene (TIPB) by hydrolysis and condensation of tetraethoxysilane (TEOS). It is shown that the morphology of the mesoporous silica is mainly controlled by the molar ratio of TIPB : P123. Cylindrical- channel (rod-like) mesoporous silica with hexagonal structure was obtained at low molar ratio of TIPB : P123, while a vesicle-like mesoporous silica was prepared at high molar ratio of TIPB : P123. TIPB at low concentration was merely dissolved into the hydrophobic core of the P123 cylindrical micelle, but it was forced to spread into the palisade layer at high concentration and ultimately transformed the cylindrical micelle phase into the MLV phase. The key role of TIPB has been demonstrated in increasing the average packing parameter (P) of P123, and this opens the way to synthesize vesicle-like silica simply by controlling the molar ratio of TIPB : P123.