Narrow Results

Porous NiTi shape memory alloy (SMA) with 48% porosity and an average pore size of 50–800 μm was synthesized by capsule-free hot isostatic pressing (CF-HIP). To enhance the surface bioactivity, the porous NiTi SMA was subjected to H₂O₂ and subsequent NaOH treatment. Scanning electron microscopy, X-ray diffraction, and X-ray photoelectron spectroscopy analyses revealed that a porous sodium titanate (Na₂TiO₃) film had formed on the surface of the porous NiTi SMA. An apatite layer was deposited on this film after immersion in simulated body fluid at 37°C, while no apatite could be found on the surface of the untreated porous NiTi SMA. The formation of the apatite layer infers that the bioactivity of the porous NiTi SMA may be enhanced by surface chemical treatment, which is favorable for its application as bone implants.

Liquid-infused porous surfaces inspired by Nepenthes pitcher plant were fabricated on polyurethane. Five different micro-structures, including pillar (PIL), Sharklet${}^{\circledR }$ (SHK), continuous discrete ridge (DIR), hole (HOL) and networking (NET), were fabricated by soft lithography. Effects of micro-structural geometry on lubricant infiltration capability were investigated by infiltration the micro-structures with two lubricants of different viscosity, Krytox-103 ($\eta$: 0.131 $\mathrm{\text{Pa}}\cdot \mathrm{\text{s}}$) and Krytox-105 ($\eta :0.737\mathrm{\text{Pa}}\cdot \mathrm{\text{s}}$). The lubricant infiltration and retention capability were determined using a confocal laser scanning micro-scopy, and properties of the infused surfaces were evaluated by measuring the speed of water droplet motion at various tilting angles. The results revealed that, for the 80$\mu$m-high micro-structures, infiltration with a less viscous Krytox-103 resulted in more complete infiltration and retention, particularly for the PIL micro-structure. The infused surface exhibited a slippery behavior signified by low sliding angle and good anti-adhesion against chlorophyll fluid and milk yogurt. The lubricant retention capability was significantly reduced for the 7$\mu$m-high micro-structures due to lower aspect ratio and low capillary force. In this case, the PIL infused with a more viscous Krytox-105 provided a slippery surface.

INDIA – A novel form of gene regulation in bacteria.

INDIA – Algal biofuels are no energy panacea.

JAPAN – Medical Data Vision enhances the quality of medical care with Actian Vectorwise.

SINGAPORE – Singapore heart surgeon to receive honour from The Royal College of Surgeons of Edinburgh.

SINGAPORE – ELGA^® to deliver innovative water purification at new Singapore General Hospital expansion.

AUSTRALIA – Specialised Therapeutics Australia: New drug to fight hospital superbug infection.

AUSTRALIA – Group of genes hold the clue in migraine cases.

AUSTRALIA – CT scans can triple risk of brain cancer, leukemia.

BRAZIL – Science can do more for sustainable development.

MIDDLE EAST – Particles and persecution: why we should care about Iranian physicists.

EUROPE – Medicyte coordinates EU-funded collaboration on Biomimetic Bioartificial Liver.

EUROPE – Selvita and Orion Pharma achieve a research milestone in Alzheimer's Disease Program.

EUROPE – Zinforo (ceftaroline fosamil) receives positive CHMP opinion in the European Union for the treatment of patients with serious skin infections or community acquired pneumonia.

USA – Vein grown from girl's own stem cells transplanted.

USA – Hidden vitamin in milk yields remarkable health benefits - Weill Cornell researchers show tiny vitamin in milk, in high doses, makes mice leaner, faster and stronger.

USA – New report finds biotechnology companies are participating in 39% of all projects in development for new medicines and technologies for neglected diseases.

USA – TriReme Medical receives FDA clearance for expanded matrix of sizes of Chocolate PTA balloon catheter.

USA – New data show investigational compound dapagliflozin demonstrated significant reductions in blood sugar levels when added to sitagliptin in adults with type 2 diabetes at 24 weeks, with results maintained over 48 weeks.

USA – Zalicus successfully completes Phase 1 single ascending dose study with Z944, a novel, oral T-Type Calcium Channel Blocker.

USA – Study provides clues to clinical trial cost savings.

Through millions of years' natural selection, creature has formed their own unique functional surfaces. Shark is one of the fastest animals in the ocean, which is well known for "sharkskin effect". Sharkskin surface is all covered by tiny and rigid scales with sophisticated morphology, which is one important factor to produce the high drag reducing efficiency. However, the drag reduction mechanism of sharkskin has not been understood thoroughly, which has developed into an urgent problem to be resolved. In this paper, the accurate 3D digital model of sharkskin surface is constructed based on the biological prototype and the micro flow field on the near wall is analyzed comprehensively and deeply. In addition, the drag reduction mechanism is explored from different aspects, especially which, the influences of the variation of attack angles of scales, the super-hydrophobic effect and nanochain of mucus on drag-reducing efficiency are taken into consideration, which has great significance on academic research and engineering application.

In this work, we report the facile formation of bimetallic nanoparticles of Au–Pt in the presence of the plant polyphenol ellagic acid (EA). It was found that EA formed micro-fibrillar assemblies, which aggregated into micro-bundles under aqueous conditions. Those micro-bundles acted as templates for the growth of Au nanoparticles, as well as bimetallic Au–Pt nanoparticles biomimetically. At higher concentrations of EA, it was observed that in addition to forming fibrous micro-bundles, columnar assemblies of EA were formed in the presence of the metal nanoparticles. The formation of the assemblies was found to be concentration dependent. It appears that upon binding to metal ions and subsequent formation of the nanoparticles, morphological changes occur in the case of EA assemblies. The morphological changes observed were probed by electron microscopy. Further, the ability of the materials to degrade the toxic aromatic nitro compound 2-methoxy-4-nitroaniline was explored, where 50% degradation was observed within 15 min, indicating that such hybrid materials may have potential applications in environmental remediation.

The synthesis, characterization and application of biologically synthesized nanomaterials have become an important branch of nanotechnology. In the present study, we report the synthesis of silver nanoparticles from fresh leaf extract of Centella asiatica (LEC). UV-Vis spectrum for silver colloids contains a strong plasmon band near 425nm, which confirms the formation of nanoparticles. The experimental results show that the silver nanoparticles are formed easily in the extract at ambient temperature. The resulting silver nanoparticles (AgNPs) were in the spherical form and the average size of the nanoparticles was in the range from 3nm to 30nm. From the above silver nanoparticles, we were taken up to investigate the effects of various concentrations of AgNPs on growth, development and yield of peanut plants. The results of the present experiment showed that the optimized concentration of AgNPs of the good germination, growth and pod yield of peanut plant is 5ppm.

The aim of this paper is trying to propose an efficient method of inverse kinematics and motion generation for redundant humanoid robot arm based on the intrinsic principles of human arm motion. The intrinsic principle analysis takes into account both the skeletal kinematics and muscle strength properties. Firstly, this work analyzed the kinematic redundancy problem of a human arm. By analyzing the biological feature of a human arm, the kinematic redundancy boils down to the uncertainty of elbow position. Secondly, because the muscle’s kinematic and strength properties are critical for simulating biometric motion authentically, the muscle strength property was introduced as the criterion for configuration identification and motion generation. Three types of limb configuration, dog walking, gecko climbing, and human walking limb configuration were analyzed, and two geometrical configuration identification rules were deduced to generate biomimetic motion for humanoid robotic arms. By comparing the proposed method with other five IK methods, the proposed method significantly deduced the computing time. Finally, the configuration identification rules were used to generate motions for a 7-DoF humanoid robotic arm. The results showed that the biological rules can generate biomimetic, smooth arm motions for a redundant humanoid robotic arm.

Poly(phenylacetylene)s bearing monosaccharide pendant groups are synthesized in high yields by [Rh(nbd)Cl]₂ catalyst. The polymers have high molecular weights and give satisfactory spectroscopic data corresponding to their molecular structures. They are thermally quite stable (≥ 300°C) and show strong circular dichroism signals in the visible spectral region owing to the helicity of the polyene backbone. The monosaccharide-containing polyacetylenes are cytophilic and can stimulate the growth of living cells.

Cyclodextrins are versatile building blocks for a variety of macromolecules due to the inclusion complexes that are formed with hydrophobic organic molecules. Cyclodextrin-porphyrin interactions are of particular interest since cyclodextrins can serve as a non-covalent binding pocket while metalloporphyrins could serve as the heme analogs in the construction of heme protein model compounds. Various approaches to the design and assembly of biomimetic porphyrin constructs are compared and contrasted in this minireview with a particular emphasis on self-assembled and porphyrin-cyclodextrin systems. Several recent advances from our laboratories are described in this context. A sensitive fluorescent binding probe, 6^A-N-dansyl-permethylated-β-cyclodextrin (Dan-NH-TMCD), was found to form 2:1 complexes with the meso-tetraphenylporphyrins Mn(III)TCPP, Mn(III)TPPS and Mn(III)TF₄TMAP with high binding constants. A perPEGylated cyclodextrin, heptakis(2,3,6-tri-O-2-(2-(2-methoxyethoxy)ethoxy)ethyl)-β-cyclodextrin (TPCD), has been shown by ¹H NMR spectroscopy to form a 1:1 complex with H₂TCPP with a binding constant above 10⁸M^-1. Such a strong binding constant is the largest found for a 1:1 complex between a monomeric cyclodextrin and a guest. TPCD was also found to bind Mn(III)TCPP with a binding constant of 1.2 × 10⁶M^-1. A novel, self-assembled hemoprotein model, hemodextrin is also described. The molecular design is based on a PEGylated cyclodextrin scaffold that bears both a heme-binding pocket and an axial ligand that binds an iron porphyrin. The binding constant for Fe(III)TPPS (iron(III) meso-tetra(4-sulfonatophenyl)porphyrin) by py-PPCD was determined to be 2 × 10⁶M^-1. The pyridyl nitrogen of py-PPCD was shown to ligate to the iron center by observing signal changes in the Fe(II)-porphyrin ¹H NMR spectrum. This hemodextrin ensemble, a minimalist myoglobin, was shown to bind dioxygen reversibly and to form a stable ferryl species.

A novel industrial-scale trial for cyclohexane oxidation with air over metalloporphyrins as cytochrome P-450 monooxygenase model was reported. Upon addition of extremely low concentrations (1–5 ppm) of simple cobalt porphyrin to the commercial cyclohexane oxidation system, and decrease of the reaction temperature and pressure about 20 °C and 0.4 MPa respectively, the conversion rate of the cyclohexane oxidation increased from 4.8% to 7.1%, the yield of cyclohexanone raised from 77% to 87%, and a 70,000-ton cyclohexanone equipment set yielded an output of 125,000 tons cyclohexanone. Furthermore, a novel biological-chemical-cycle coupling mechanism was proposed to rationalize the aerobic oxidations of hydrocarbons catalyzed by the metalloporphyrins.

Numerical simulations for local buckling and postbuckling behavior of plant stems are presented under two combined loading cases: (1) axial compression (caused by axial grains) combined with wind pressure; and (2) bending moment (caused by eccentric axial grains) combined with wind pressure. Based on its microstructure, a hollow plant stem is modeled as a stringer stiffened multiwalled shell. The material properties of the stem are assumed to be orthotropic. The nonlinear governing equations for buckling and postbuckling of plant stems are solved through arc-length method along with Newton–Raphson technique. The numerical calculations are carried out using the finite element package ABAQUS. The results show that the postbuckling equilibrium path is unstable for plant stems subjected to axial compression or bending combined with relatively low values of wind pressure. Large reduction in buckling load and in postbuckling strength can be found even if the applied wind pressure is relatively small, which results in the easy occurrence of stem lodging.

Pinecone scales and seedpod valves can deform in response to environmental humidity change, which is categorized as nastic movements. In this article, inspired by their tissue structure, we use fiber-embedded gels to model the nastic movements of pinecone scales and seedpod valves. In the model, stiffer and less swellable fibers orient inhomogeneously in the gel matrix. Depending on the arrangement of fibers, the gel matrix may bend or twist when it shrinks, caused by the decrease of environmental humidity. Our simulations demonstrate the possibilities of achieving different deformation modes in fiber-embedded gels through initially specified fiber arrangements. The numerical modeling methods presented in the article may find their applications in biomimetic designs with responsive gels.

To repair bone defects, an important approach is to fabricate tissue engineering scaffolds as substitutions to replace auto-/allologous bones. Currently, processing a biomaterial into three-dimensional porous scaffolds and incorporating the calcium phosphate (Ca–P) nanoparticles into scaffolds profile two main characteristics of bone tissue engineering scaffolds. Based on this fact, in this paper we describe the design principles of the Ca–P nanoparticle-based and porous bone tissue engineering scaffolds. Then we summarize a variety of the Ca–P nanoparticle-based scaffolds, including discussion of the integration of the Ca–P nanoparticles with ceramics and polymers, followed by introduction of safety of the Ca–P nanoparticles in scaffolds.

Hierarchical self-assembling of materials represents one of the most appealing subjects in nanoscience, since bottom-up strategies allow for tailor-made synthesis of functional structures in commodities as well as in living systems. Herein we show that nanorings of ca. 10nm silica nanoparticles without any inorganic metal oxide or organic participant are able to spontaneously self-assemble presenting sophisticated forms and hierarchy. It was observed that after synthesis, silica nanoparticles are chaotically distributed but during storage at ambient conditions they spontaneously form self-assembled aggregates with multiplicity of morphologies when a small amount of water is added in the environment. Detailed description of the morphology of such structures by high resolution transmission electron microscope (HRTEM) is presented together with a discussion about the role of water during their spontaneous formation.

In this study, poly (lactic acid-glycolic acid) (PLGA) nanoparticles loaded with anti-inflammatory drug ketoprofen (KET) were prepared and then coated with platelet membrane (PLTM) to form KET@PLTM-PLGA nano-particles (NPs). The particle size of the KET@PLTM-PLGA NPs is 176nm and the surface protein is the same as that of PLTM. The results of confocal microscopy and flow cytometry showed that the KET@PLTM-PLGA NPs uptake of RAW264.7 induced by LPS was significantly higher than that of KET@PLGA NPs, without PLTM, which was due to the binding of P-selectin to CD44 receptors on the surface of RAW264.7 cells induced by LPS on the surface of PLTM. Compared with other KET preparations, KET@PLTM-PLGA NPs have better anti-inflammatory effect.

We present a facile green biomimetic synthesis of FePt nanoparticles (NPs) on the sidewalls of multi-walled carbon nanotubes (CNTs). A core-shell globular protein, ferritin (Fr), was bound onto Z-glycine N-succinimidyl ester (Z-Gly-OSu) modified CNTs and served as precursor to create FePt NPs at the core part of Fr. Biomimetic synthesis of FePt NPs was carried out by chemical reducing of Fe²⁺ and ions that transferred into the core part of Fr molecules. The created one-dimensional CNT-FePt nanohybrids were characterized by transmission electron microscopy and X-ray photoelectron spectroscopy. The synthesized CNT-FePt nanohybrids show multi-properties of high water-solubility, ferromagnetism, and electrocatalytic activity.

We demonstrated a biomimetic green synthesis of bimetallic Au–Ag nanoparticles (NPs) on graphene nanosheets (GNs). The spherical protein, ferritin (Fr), was bound onto GNs and served as the template for the synthesis of GN/Au–Ag nanohybrids. The created GN/Au–Ag nanohybrids were further utilized to fabricate a non-enzymatic amperometric biosensor for the sensitive detection of hydrogen peroxide (H₂O₂), and this biosensor displayed high performances to determine H₂O₂ with a detection limit of 20.0 × 10^-6 M and a linear detection range from 2.0 μM to 7.0 mM.

In this study, in-silico interaction analysis between Human serum albumin (HSA) and serum protein acidic and rich in cysteine (SPARC)–Collagen complex was performed to determine the binding affinity between the two proteins. Structure-based molecular interaction studies of the HSA–SPARC–Collagen complex were performed using ClusPro 2.0, ZDOCK and PatchDock servers. Molecular dynamics analysis was performed for the first-ranked complex structure (HSA–SPARC–Collagen complex) using GROMACS for a period of 125 nanoseconds to determine the stability of the complex. The results show higher structural interactive cumulative scores between the HSA and SPARC–Collagen complex. HSA–SPARC–Collagen complex predominantly has the Pi-alkyl and Pi-sigma interactions. The root mean square fluctuation (RMSF), root mean square deviation, solvent accessible surface area, radius of gyration and the number of hydrogen bonds show that formed complex is stable. In conclusion, our study provides an add-on for tuning drugs concerning albumin as a drug carrier by targeting the SPARC–Collagen complex for treating different ailments.

Hydroxyapatite (HAp) is the major inorganic component in human bones and well known for its biocompatibility. It has been widely prepared in many forms for orthopedic and dental applications. Color-center-doped HAps are also prevalently used as fluorescent materials. Further, HAp based photoluminescent material might be an ideal agent for bioimaging. Moreover, self-assembly of HAp in calcium- and phosphate-containing solutions gains a lot of attention because organic–inorganic HAp hybrids can be tailor-made. In this study, the author used a biomimetic process to synthesize organic–inorganic HAp nano hybrid at room temperature. The natural and synthesized polymeric templates used to prepare the organic–inorganic HAp hybrids were collagen, PEG–PLGA (di block), and PEG–PLGA–PEG (tri block), respectively. X-ray diffraction (XRD) diagrams revealed that the synthesized powders had crystalline HAp phase, and transmission electron microscope (TEM) photographs showed their nano grain structure. Characterization using XRD, TEM, and Fourier transform infrared spectrometer (FTR) indicated the existence of crystalline HAp phase and the variation in HAp shape versus different polymers in the composite powders. The measurement of photoluminescent (PL) spectra used a 325 nm He–Cd laser as source. The di HAp and tri HAp emitted light with a wide range of wavelength from 350 to 550 nm, much stronger than pure HAp. Collagen alone emitted brighter fluorescence peaked around 410 nm but was quickly quenched, while collagen–HAp composite powders emitted sustaining PL light peaking around 415 nm. The developed PL bioceramics are of great potential in bio sensing and bio optoelectronics.

With the benefit of millions of years of natural selection, it is no surprise that when it comes to fitting form to function, Nature is second to none in engineering the right structure for the right job. The creation of architectural elegance, despite using the minimal amount of material has long fascinated man, who has endeavored to understand how intricate construction can be accomplished merely through the flow of inorganic ions and strategically placed macromolecules. When the demands of the environment are the blueprints of the construction, structures are produced with the utmost efficiency. This was first stated explicitly by D'Arcy Thompson, in his seminal work On Growth and Form (1917).¹ However, even as far back as the 16th century, scientist and astronomer Johannes Kepler noted that “Nature uses as little as possible of anything”. Both these and many other luminaries held Nature in the highest esteem as an engineer par excellence.

In the 19th century, people used these tenets and took their inspiration for daring and innovative architectural and engineering projects from Nature. In the 21st century therefore, when advanced nanoscale materials are required, it is only right that man should once again turn to Nature for solutions to their creation.