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Histogram parameters derived from T1 and T2 weighted images correlate with tumor infiltrating lymphocytes and tumor-stroma ratio in head and neck squamous cell cancer.

Magn Reson Imaging 2021 May 7. Epub 2021 May 7.

Department of Diagnostic and Interventional Radiology, University of Magdeburg, Germany.

Purpose: The present study used histogram analysis values derived from T1- and T2- weighted (w) images to elucidate possible associations with Tumor-infiltrating lymphocytes (TIL) and Vimentin expression in head and neck squamous cell cancer (HNSCC).

Materials And Methods: Overall, 28 patients (n = 8 female patient, 28.6%) with primary HNSCC of different localizations were involved in the study. Read More

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Crystal structures of NAD-linked isocitrate dehydrogenase from the green alga Ostreococcus tauri and its evolutionary relationship with eukaryotic NADP-linked homologs.

Arch Biochem Biophys 2021 May 3:108898. Epub 2021 May 3.

Anhui Provincial Key Laboratory of Molecular Enzymology and Mechanism of Major Diseases and Key Laboratory of Biomedicine in Gene Diseases and Health of Anhui Higher Education Institutes, No.1 Beijing East Road, College of Life Sciences, Anhui Normal University, Wuhu, Anhui, 241000, China. Electronic address:

NAD-linked isocitrate dehydrogenases (NAD-IDHs) catalyze the oxidative decarboxylation of isocitrate into α-ketoglutarate. Previously, we identified a novel phylogenetic clade including NAD-IDHs from several algae in the type II subfamily, represented by homodimeric NAD-IDH from Ostreococcus tauri (OtIDH). However, due to its lack of a crystalline structure, the molecular mechanisms of the ligand binding and catalysis of OtIDH are little known. Read More

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X-ray diffraction investigation of electric-field-induced switching in a hybrid improper ferroelectric.

J Appl Crystallogr 2021 Apr 18;54(Pt 2):533-540. Epub 2021 Mar 18.

Department of Chemistry, University of Warwick, Coventry, United Kingdom.

Improper ferroelectric mechanisms are increasingly under investigation for their potential to expand the current catalogue of functional materials whilst promoting couplings between ferroelectricity and other technologically desirable properties such as ferromagnetism. This work presents the results of an synchrotron X-ray diffraction experiment performed on samples of CaSrTiO in an effort to elucidate the mechanism of hybrid improper ferroelectric switching in this compound. By simultaneously applying an electric field and recording diffraction patterns, shifts in the intensity of superstructure peaks consistent with one of the switching mechanisms proposed by Nowadnick & Fennie [, (2016), , 104105] are observed. Read More

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Structural and functional studies of SAV1707 from Staphylococcus aureus elucidate its distinct metal-dependent activity and a crucial residue for catalysis.

Acta Crystallogr D Struct Biol 2021 May 14;77(Pt 5):587-598. Epub 2021 Apr 14.

Research Institute of Pharmaceutical Sciences, College of Pharmacy, Seoul National University, Seoul 08826, Republic of Korea.

The metallo-β-lactamase fold is the most abundant metal-binding domain found in two major kingdoms: bacteria and archaea. Despite the rapid growth in genomic information, most of these enzymes, which may play critical roles in cellular metabolism, remain uncharacterized in terms of structure and function. In this study, X-ray crystal structures of SAV1707, a hypothetical metalloenzyme from Staphylococcus aureus, and its complex with cAMP are reported at high resolutions of 2. Read More

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Plasmodium chitinases: revisiting a target of transmission-blockade against malaria.

Protein Sci 2021 May 2. Epub 2021 May 2.

Tata Institute for Genetics and Society, Center at inStem, Bengaluru, India.

Malaria is a life-threatening disease caused by one of the five species of Plasmodium, among which Plasmodium falciparum cause the deadliest form of the disease. Plasmodium species are dependent on a vertebrate host and a blood-sucking insect vector to complete their life cycle. Plasmodium chitinases belonging to the GH18 family are secreted inside the mosquito midgut, during the ookinete stage of the parasite. Read More

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A large-scale structural and functional connectome of social mentalizing.

Neuroimage 2021 Apr 30;236:118115. Epub 2021 Apr 30.

Department of Psychology, Temple University, Philadelphia, PA, USA. Electronic address:

Humans have a remarkable ability to infer the mind of others. This mentalizing skill relies on a distributed network of brain regions but how these regions connect and interact is not well understood. Here we leveraged large-scale multimodal neuroimaging data to elucidate the brain-wide organization and mechanisms of mentalizing processing. Read More

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Structural insights from an in silico molecular docking simulation of complement component 3a receptor 1 with an antagonist.

J Mol Graph Model 2021 Apr 5;106:107914. Epub 2021 Apr 5.

Cellular and Molecular Biotechnology Research Institute, National Institute of Advanced Industrial Science and Technology, 2-4-7 Aomi, Koto-ku, Tokyo, 135-0064, Japan; Transborder Medical Research Center, University of Tsukuba, 1-1-1 Tennodai, Tsukuba, Ibaraki, 305-8575, Japan; Division of Biomedical Science, Faculty of Medicine, University of Tsukuba, 1-1-1 Tennodai, Tsukuba, Ibaraki, 305-8575, Japan. Electronic address:

Complement component 3a receptor 1 (C3aR) is an anaphylatoxin receptor that mediates inflammatory processes. Although considerable effort has gone into discovering the antagonists and agonists of C3aR, structural insights are required to search for effective ligands and to elucidate their binding modes and the mechanism of activation and inactivation. No experimental structural data of C3aR have yet been reported. Read More

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Detection of the hybrid layer biodegradation initiation factor with a scanning electron microscope.

Microsc Res Tech 2021 Apr 30. Epub 2021 Apr 30.

Department of Prosthodontics, School of Dentistry, Ege University, Izmir, Turkey.

The purpose of this study was to elucidate the origin of initiation of hybrid layer biodegradation. Ninety caries-free human third molars were divided into three surface groups: enamel, dentin, and NaOCl-treated dentin. (n = 30/group) Each group was divided into three subgroups (n = 10/group) of luting resin materials with etch-and-rinse; self-etch and self-adhesive systems. Read More

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The Unique Fiber Anatomy of Middle Temporal Gyrus Default Mode Connectivity.

Oper Neurosurg (Hagerstown) 2021 Apr 30. Epub 2021 Apr 30.

Centre for Minimally Invasive Neurosurgery, Prince of Wales Private Hospital, Sydney, Australia.

Background: The middle temporal gyrus (MTG) is understood to play a role in language-related tasks such as lexical comprehension and semantic cognition. However, a more specific understanding of its key white matter connections could promote the preservation of these functions during neurosurgery.

Objective: To provide a detailed description of the underlying white matter tracts associated with the MTG to improve semantic preservation during neurosurgery. Read More

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Allosteric Modulation of the CB1 Cannabinoid Receptor by Cannabidiol-A Molecular Modeling Study of the N-Terminal Domain and the Allosteric-Orthosteric Coupling.

Molecules 2021 Apr 23;26(9). Epub 2021 Apr 23.

Biological and Chemical Research Centre, Faculty of Chemistry, University of Warsaw, 02093 Warsaw, Poland.

The CB cannabinoid receptor (CBR) contains one of the longest N termini among class A G protein-coupled receptors. Mutagenesis studies suggest that the allosteric binding site of cannabidiol (CBD) involves residues from the N terminal domain. In order to study the allosteric binding of CBD to CBR we modeled the whole N-terminus of this receptor using the replica exchange molecular dynamics with solute tempering (REST2) approach. Read More

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Post-exercise Cold Water Immersion Effects on Physiological Adaptations to Resistance Training and the Underlying Mechanisms in Skeletal Muscle: A Narrative Review.

Front Sports Act Living 2021 8;3:660291. Epub 2021 Apr 8.

Deakin University, Institute for Physical Activity and Nutrition (IPAN), School of Exercise and Nutrition Science, Geelong, VIC, Australia.

Post-exercise cold-water immersion (CWI) is a popular recovery modality aimed at minimizing fatigue and hastening recovery following exercise. In this regard, CWI has been shown to be beneficial for accelerating post-exercise recovery of various parameters including muscle strength, muscle soreness, inflammation, muscle damage, and perceptions of fatigue. Improved recovery following an exercise session facilitated by CWI is thought to enhance the quality and training load of subsequent training sessions, thereby providing a greater training stimulus for long-term physiological adaptations. Read More

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Locomotor transitions in the potential energy landscape-dominated regime.

Proc Biol Sci 2021 Apr 21;288(1949):20202734. Epub 2021 Apr 21.

Department of Mechanical Engineering, Johns Hopkins University, 3400 N. Charles Street, Baltimore, MD 21218, USA.

To traverse complex three-dimensional terrain with large obstacles, animals and robots must transition across different modes. However, the most mechanistic understanding of terrestrial locomotion concerns how to generate and stabilize near-steady-state, single-mode locomotion (e.g. Read More

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SC5005 dissipates the membrane potential to kill Staphylococcus aureus persisters without detectable resistance.

J Antimicrob Chemother 2021 Apr 14. Epub 2021 Apr 14.

Department of Clinical Laboratory Sciences and Medical Biotechnology, College of Medicine, National Taiwan University, Taipei 10048, Taiwan.

Objectives: In the past few decades, multiple-antibiotic-resistant Staphylococcus aureus has emerged and quickly spread in hospitals and communities worldwide. Additionally, the formation of antibiotic-tolerant persisters and biofilms further reduces treatment efficacy. Previously, we identified a sorafenib derivative, SC5005, with bactericidal activity against MRSA in vitro and in vivo. Read More

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Fitness for purpose of stabilized stool samples for bile acid metabolite analyses.

Sci Rep 2021 Apr 12;11(1):7904. Epub 2021 Apr 12.

Laboratoire National de Sante (LNS), 1, Rue Louis Rech, L-3555, Dudelange, Luxembourg.

Biobanks and cohort studies are increasingly utilizing chemical stabilizers to collect and store stool samples for downstream DNA-based microbiome analyses. While stabilizers permit ambient-temperature collection and storage of samples for gut microbiome studies, the use of the same sample type for downstream metabolomics assays has not been explored. Microbiome-metabolomics analysis of fecal samples is increasingly getting attention to further elucidate the mechanisms by which the gut microbiota influences the host. Read More

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LncRNA ACTA2-AS1 suppress colon adenocarcinoma progression by sponging miR-4428 upregulation BCL2L11.

Cancer Cell Int 2021 Apr 12;21(1):203. Epub 2021 Apr 12.

Department of General Surgery, The Fifth Hospital of Wuhan, Wuhan, 430000, Hubei, People's Republic of China.

Background: Long non-coding RNA is considered to be essential to modulate the development and progression of human malignant cancers. And long non-coding RNA can act as crucial modulators by sponging the corresponding microRNA in tumorigenesis. We aimed to elucidate the function of ACTA2-AS1 and its molecular mechanism in colon adenocarcinoma. Read More

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Morphea: progress to date and the road ahead.

Ann Transl Med 2021 Mar;9(5):437

Department of Dermatology, University of Texas Southwestern Medical Center, Dallas, Texas, USA.

Morphea is a rare autoimmune condition causing inflammation and sclerosis of the skin and underlying soft tissue. It is characterized by periods of activity (inflammation admixed with fibrosis), ultimately resulting in permanent damage (pigment change and tissue loss). Damage resulting from unchecked activity can lead to devastating, permanent cosmetic and functional sequelae including hair loss; cutaneous, soft tissue and bony atrophy; joint contractures; and growth restriction of the affected body site in children. Read More

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Mechanism of antimicrobial activity of honeybee (Apis mellifera) venom on Gram-negative bacteria: Escherichia coli and Pseudomonas spp.

AMB Express 2021 Apr 9;11(1):54. Epub 2021 Apr 9.

School of Chemical Engineering, University of Birmingham, Edgbaston, Birmingham, B15 2TT, UK.

Honeybee venom (Apitoxin, BV), a secretion substance expelled from the venom gland of bees, has being reported as antimicrobial against various bacterial species; however, the mechanism of action remains uncharacterized. In this study, the antibacterial activity of BV was investigated on hygiene indicator Escherichia coli and the environmental pathogen and spoilage bacterial species, Pseudomonas putida and Pseudomonas fluorescens. An array of methods was combined to elucidate the mode of action of BV. Read More

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Manipulating mode degeneracy for tunable spectral characteristics in multi-microcavity photonic molecules.

Opt Express 2021 Mar;29(7):11181-11193

Optical microcavities are capable of confining light to a small volume, which could dramatically enhance the light-matter interactions and hence improve the performances of photonic devices. However, in the previous works on the emergent properties with photonic molecules composed of multiple plasmonic microcavities, the underlying physical mechanism is unresolved, thereby imposing an inevitable restriction on manipulating degenerate modes in microcavity with outstanding performance. Here, we demonstrate the mode-mode interaction mechanism in photonic molecules composed of degenerate-mode cavity and single-mode cavity through utilizing the coupled mode theory. Read More

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Identification of a critical binding site for local anesthetics in the side pockets of Kv1 channels.

Br J Pharmacol 2021 Apr 4. Epub 2021 Apr 4.

Institute for Physiology and Pathophysiology, University of Marburg, Marburg, Germany.

Background And Purpose: Local anesthetics block sodium and a variety of potassium channels. Although previous studies identified a residue in the pore signature sequence together with three residues in the S6 segment as a putative binding site, the precise molecular basis of Kv potassium channel inhibition by local anesthetics remained unknown. Kv crystal structures predict that some of these residues point away from the central cavity and face into a drug binding site called side pockets. Read More

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Systematic Development of a Size Exclusion Chromatography Method for a Monoclonal Antibody with High Surface Aggregation Propensity (SAP) Index.

J Pharm Sci 2021 Apr 1. Epub 2021 Apr 1.

BMS Analytical Development & Analytical Attribute Science in Biologics, 38 Jackson Rd, Devens, MA 01434.

Size Exclusion Chromatography (SEC) has been widely used to assess aggregate content in bio-pharmaceutical drugs such as monoclonal antibodies (mAbs), and is routinely used during method development and release testing. Electrostatic interactions between protein analytes and SEC column resin are commonly observed besides the primary mode of size separation during SEC method development, which needs to be minimized. An effective method to minimize electrostatic interactions is through increasing mobile phase (MP) salt concentration. Read More

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Effect of a Moral Distress Consultation Service on Moral Distress, Empowerment, and a Healthy Work Environment.

HEC Forum 2021 Apr 3. Epub 2021 Apr 3.

Center for Health Humanities and Ethics, University of Virginia Center for Health Humanities and Ethics, PO Box 800758, Charlottesville, VA, 22908, USA.

Background:  Healthcare providers who are accountable for patient care safety and quality but who are not empowered to actualize them experience moral distress. Interventions to mitigate moral distress in the healthcare organization are needed.

Objective:  To evaluate the effect on moral distress and clinician empowerment of an established, health-system-wide intervention, Moral Distress Consultation. Read More

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Chronic Opioid Administration is Associated with Prevotella-dominated Dysbiosis in SIVmac251 Infected, cART-treated Macaques.

J Neuroimmune Pharmacol 2021 Mar 31. Epub 2021 Mar 31.

Department of Pharmacology and Experimental Neuroscience, University of Nebraska Medical Center, Omaha, NE, USA.

People living with the human immunodeficiency virus (HIV) have an elevated risk of opioid misuse due to both prescriptions for HIV-associated chronic pain and because injection drug use remains a primary mode of HIV transmission. HIV pathogenesis is characterized by chronic immune activation and microbial dysbiosis, and translocation across the gut barrier exacerbating inflammation. Despite the high rate of co-occurrence, little is known about the microbiome during chronic opioid use in the context of HIV and combination antiretroviral therapy (cART). Read More

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Geographical distribution of the dispersal ability of alien plant species in China and its socio-climatic control factors.

Sci Rep 2021 Mar 30;11(1):7187. Epub 2021 Mar 30.

CAS Key Laboratory of Forest Ecology and Management, Institute of Applied Ecology, Chinese Academy of Sciences, Shenyang, 110016, China.

Dispersal ability is important for the introduction, establishment, and spread of alien plant species. Therefore, determination of the geographical distribution of the dispersal ability of such species, and the relationship between dispersal ability and socio-climatic factors are essential to elucidate the invasion strategies of the alien plant species. Analytic hierarchy process and inventory, risk rank, and dispersal mode data available on Chinese alien plant species were used to determine their dispersal ability, the geographical distribution thereof, and the relationship between socio-climatic factors and dispersal ability. Read More

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Nifuroxazide as JAK2 inhibitor: A binding mode proposal and Hel cell proliferation assay.

Eur J Pharm Sci 2021 Mar 26;162:105822. Epub 2021 Mar 26.

Grupo de Pesquisas Químico-Farmacêuticas, Departamento de Ciências Farmacêuticas, Instituto de Ciências Ambientais, Químicas e Farmacêuticas, Universidade Federal de São Paulo, Campus Diadema. Electronic address:

Nifuroxazide has been employed as an anti-diarrheic agent since 1966, but in the last decade has brought to the research spotlight again due to its recently described antitumoral activity through the JAK2 inhibitory potential. Since 2008, more than 70 papers have been published about the issue and more are expected to the following years. Herein we discuss the findings of molecular modelling studies which were performed to elucidate the potential binding mode of this drug into the JAK2 ATP recognition site and also into the allosteric region near the catalytic site. Read More

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Indole-3-carbinol induces apoptosis-like death in Escherichia coli on different contribution of respective reactive oxygen species.

Life Sci 2021 Jun 24;275:119361. Epub 2021 Mar 24.

School of Life Sciences, BK 21 FOUR KNU Creative BioResearch Group, College of Natural Sciences, Kyungpook National University, 80 Daehakro, Bukgu, Daegu, 41566, Republic of Korea. Electronic address:

Aims: Indole-3-carbinol (I3C) is a natural compound derived from brassica vegetables, displaying antibacterial activity. The study aims to elucidate the antibacterial mode of action(s) induced by indole-3-carbionol in Escherichia coli and enhance the understandings on the respective contribution of each reactive oxygen species (ROS), superoxide anion (O), hydrogen peroxide (HO), hydroxyl radical (OH) during the process.

Main Methods: The antibacterial activity of I3C was assessed through kinetic assay. Read More

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Touch-Cure Polymerization at the Composite Cement-Dentin Interface.

J Dent Res 2021 Mar 26:220345211001020. Epub 2021 Mar 26.

KU Leuven (University of Leuven), Department of Oral Health Sciences, BIOMAT & UZ Leuven (University Hospitals Leuven), Dentistry, Leuven, Belgium.

Ceramic restorations are often adhesively luted onto the tooth prep. The so-called touch-cure concept was developed to yield optimum polymerization of composite cement at the restoration-cement-tooth interface for immediate bond stabilization. Although this touch cure is theorized to initiate polymerization at the interface when the accelerator in the primer makes contact with the cement, this process has not yet been proven. Read More

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High spatial and energy resolution electron energy loss spectroscopy of the magnetic and electric excitations in plasmonic nanorod oligomers.

Opt Express 2021 Feb;29(3):4661-4671

We leverage the high spatial and energy resolution of monochromated aberration-corrected scanning transmission electron microscopy to study the hybridization of cyclic assemblies of plasmonic gold nanorods. Detailed experiments and simulations elucidate the hybridization of the coupled long-axis dipole modes into collective magnetic and electric dipole plasmon resonances. We resolve the magnetic dipole mode in these closed loop oligomers with electron energy loss spectroscopy and confirm the mode assignment with its characteristic spectrum image. Read More

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February 2021

Studies on the Changes of Pharmacokinetics Behaviors of Phytochemicals and the Influence on Endogenous Metabolites After the Combination of Radix Bupleuri and Radix Paeoniae Alba Based on Multi-Component Pharmacokinetics and Metabolomics.

Front Pharmacol 2021 8;12:630970. Epub 2021 Mar 8.

Modern Research Center for Traditional Chinese Medicine of Shanxi University, Taiyuan, China.

Radix Bupleuri-Radix Paeoniae Alba (RB-RPA) is a classic herb pair, which is commonly used to treat depression by soothing "liver qi stagnation" in the clinic. However, little is yet known concerning the combination mechanism of Radix Bupleuri (RB) and Radix Paeoniae Alba (RPA), their bioactive forms and the regulatory effects on the organism. The present study aimed to elucidate the changes in multi-component pharmacokinetics (PK) behavior after the combination of RB and RPA by a high-resolution full-scan mode of UPLC-HRMS method (a total of 38 components PK profiles were obtained, of which 23 components come from RB and 15 components come from RPA). Read More

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Architecture and mechanism of metazoan retromer:SNX3 tubular coat assembly.

Sci Adv 2021 Mar 24;7(13). Epub 2021 Mar 24.

Cambridge Institute for Medical Research, Cambridge Biomedical Campus, Hills Road, Cambridge CB2 0XY, UK.

Retromer is a master regulator of cargo retrieval from endosomes, which is critical for many cellular processes including signaling, immunity, neuroprotection, and virus infection. The retromer core (VPS26/VPS29/VPS35) is present on cargo-transporting, tubular carriers along with a range of sorting nexins. Here, we elucidate the structural basis of membrane tubulation and coupled cargo recognition by metazoan and fungal retromer coats assembled with the non-Bin1/Amphiphysin/Rvs (BAR) sorting nexin SNX3 using cryo-electron tomography. Read More

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Amphiphilic Ti porous transport layer for highly effective PEM unitized regenerative fuel cells.

Sci Adv 2021 Mar 24;7(13). Epub 2021 Mar 24.

Center for Hydrogen, Fuel Cell Research, Korea Institute of Science and Technology (KIST), Seoul 02792, Republic of Korea.

Polymer electrolyte membrane unitized regenerative fuel cells (PEM-URFCs) require bifunctional porous transport layers (PTLs) to play contradictory roles in a single unitized system: hydrophobicity for water drainage in the fuel cell (FC) mode and hydrophilicity for water supplement in the electrolysis cell (EC) mode. Here, we report a high-performance amphiphilic Ti PTL suitable for both FC and EC modes, thanks to alternating hydrophobic and hydrophilic channels. To fabricate the amphiphilic PTL, we used a shadow mask patterning process using ultrathin polydimethylsiloxane (PDMS) brush as a hydrophobic surface modifier, which can change the Ti PTL's surface polarity without decreasing its electrical conductivity. Read More

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