Alternative Method For Preparation Research Articles

A New Thermal Model for Predicted Discharge Craters in Micro/Nano-EDM Considering the Non-Fourier Effect

Micro/nano-electrical discharge machining is an alternative preparation method for surface micro/nano-structures, but it is difficult to precisely control the size of the micro/nano-structures due to its unclear material removal mechanism. Thus, it is useful to study its machining mechanism to achieve high-efficiency and controlled processing. At present, most of the established EDM thermal models for predicting the discharge crater size are based on the classical Fourier heat conduction law, assuming that the conduction velocity of heat energy is infinite. However, the single-pulse discharge time of micro/nano-EDM is transitory (<1 μs), and thus, the steady state heat balance condition cannot be achieved in a single-pulse discharge time. In order to predict the size of the micro/nano electrical discharge craters more accurately, the non-Fourier effect was considered to study the temperature field distribution of micro/nano-EDM of single-pulse discharge machining. Firstly, the classical Fourier heat conduction law was modified by introducing a relaxation time. Secondly, several key factors were considered to establish the thermal model of micro/nano-EDM in single-pulse discharge machining. Subsequently, numerical simulation software was used to solve the thermal model for obtaining the temperature field distribution of the workpiece material and predicting the size of the discharge craters. Finally, the predicting accuracy of the new thermal model was evaluated by comparing the relative error between the simulated values and experimental values. The comparison results show that considering the non-Fourier effect can reduce the average error of the thermal model from 33% to 10%. The non-Fourier effect is more obvious under the shorter discharge time of a single pulse.

Low-Temperature Sintering of l-Alanine-Functionalized Metallic Copper Particles Affording Conductive Films with Excellent Oxidative Stability.

Here, the alpha amino acid l-alanine is employed as both a capping and stabilizing agent in the aqueous synthesis of submicron-sized metallic copper particles under ambient atmospheric conditions. The reduction of the copper(II) precursor is achieved using l-ascorbic acid (vitamin C) as the reducing agent. The nature of the complex formed between l-alanine and the copper(II) precursor, pH of the medium, temperature, and the relative proportion of capping agent are found to play a significant role in determining the size, shape, and oxidative stability of the resulting particles. The adsorbed l-alanine is shown to act as a barrier imparting excellent thermal stability to capped copper particles, delaying the onset of temperature-induced aerial oxidation. The stability of the particles is complemented by highly favorable sintering conditions, rendering the formation of conductive copper films at significantly lower temperatures (T ≤ 120 °C) compared to alternative preparation methods. The resulting copper films are well-passivated by residual surface l-alanine molecules, promoting long-term stability without hindering the surface chemistry of the copper film as evidenced by the catalytic activity. Contrary to the popular belief that ligands with long carbon chains are best for providing stability, these findings demonstrate that very small ligands can provide highly effective stability to copper without significantly deteriorating its functionality while facilitating low-temperature sintering, which is a key requirement for emerging flexible electronic applications.

Green Biosynthesis of Tin Oxide Nanomaterials Mediated by Agro-Waste Cotton Boll Peel Extracts for the Remediation of Environmental Pollutant Dyes.

The sustainable synthesis of metal oxide materials provides an ecofriendly and more exciting approach in the domain of a clean environment. Besides, plant extracts to synthesize nanoparticles have been considered one of the more superior ecofriendly methods. This paper describes the biosynthetic preparation route of three different sizes of tetragonal structure SnO2 nanoparticles (SNPs) from the agro-waste cotton boll peel aqueous extract at 200, 500, and 800 °C for 3 h and represents a low-cost and alternative preparation method. The samples were characterized by X-ray diffraction, Fourier transform infrared spectrophotometry, ultraviolet–visible absorption spectroscopy, high-resolution transmission electron microscopy (HR-TEM), and energy-dispersive X-ray spectroscopy. Surface area and porosity size distribution were identified by nitrogen adsorption–desorption isotherms and Brunauer–Emmett–Teller analysis. The photocatalytic properties of the SNP samples were studied against methylene blue (MB) and methyl orange (MO), and the degradation was evaluated with three different size nanomaterials of 3.97, 8.48, and 13.43 nm. Photocatalytic activities were carried out under a multilamp (125 W Hg lamps) photoreactor. The smallest size sample exhibited the highest MB degradation efficiency within 30 min than the most significant size sample, which lasted 80 min. Similarly, in the case of MO, the smallest sample showed a more superior degradation efficiency with a shorter period (40 min) than the large-size samples (100 min). Therefore, our studies suggested that the developed SNP nanomaterials could be potential, promising photocatalysts against the degradation of industrial effluents.

Structure‐Activity Relationships in Highly Active Platinum‐Tin MFI‐type Zeolite Catalysts for Propane Dehydrogenation

AbstractPt/Sn‐containing MFI zeolites prepared by one‐pot hydrothermal methods are highly active and selective catalysts for propane dehydrogenation. An alternative preparation method is reported alongside an in‐depth characterization of Pt and Sn before and after reaction. Pt species dispersed on highly‐defective Silicalite‐1 show a significantly long catalytic lifetime with an improved coke resistance, but increased Pt−Sn alloying and the (eventual) build‐up of carbon leads to deactivation.

Cartilage Repair Using Clematis Triterpenoid Saponin Delivery Microcarrier, Cultured in a Microgravity Bioreactor Prior to Application in Rabbit Model.

Cartilage tissue engineering provides a promising method for the repair of articular cartilage defects, requiring appropriate biological scaffolds and necessary growth factors to enhance the efficiency of cartilage regeneration. Here, a silk fibroin (SF) microcarrier and a clematis triterpenoid saponin delivery SF (CTS-SF) microcarrier were prepared by the high-voltage electrostatic differentiation and lyophilization method, and chondrocytes were carried under the simulated microgravity condition by a rotating cell culture system. SF and CTS-SF microspheres were relatively uniform in size and had a porous structure with good swelling and cytocompatibility. Further, CTS-SF microcarriers could sustainably release CTSs in the monitored 10 days. Compared with the monolayer culture, chondrocytes under the microgravity condition maintained a better chondrogenic phenotype and showed better proliferation ability after culture on microcarriers. Moreover, the sustained release of CTS from CTS-SF microcarriers upregulated transforming growth factor-β, Smad2, and Smad3 signals, contributing to promote chondrogenesis. Hence, the biophysical effects of microgravity and bioactivities of CTS-ST were used for chondrocyte expansion and phenotype maintenance in vitro. With prolonged expansion, SF- and CTS-SF-based microcarrier-cell composites were directly implanted in vivo to repair rabbit articular defects. Gross evaluations, histopathological examinations, and biochemical analysis indicated that SF- and CTS-SF-based composites exhibited cartilage-like tissue repair compared with the nontreated group. Further, CTS-SF-based composites displayed superior hyaline cartilage-like repair that integrated with the surrounding cartilage better and higher cartilage extracellular matrix content. In conclusion, these results provide an alternative preparation method for drug-delivered SF microcarrier and a culture method for maintaining the chondrogenic phenotype of seed cells based on the microgravity environment. CTS showed its bioactive function, and the application of CTS-SF microcarriers can help repair and regenerate cartilage defects.

Preparation of Porous Carbons Using NaOH, K2CO3, Na2CO3 and Na2S2O3 Activating Agents and Their Supercapacitor Application: A Comparative Study

AbstractThe sustainable energy development of green carbon precursors and inexpensive activating agents has gained great attention with respect to the manufacture of high‐performance electrode materials for supercapacitors. Though the most investigated activation agents such as ZnCl2 and KOH provide porous carbon possessing the high surface area and large charge storage capacity, those activation agents suffer from the use of high dosage utilization and poor carbon production yield. Herein, we report an alternative preparation method for porous carbons using NaOH, K2CO3, Na2CO3 and Na2S2O3 as activating agents, respectively. Activating performances of four pore‐forming agents were compared in terms of textural, morphological and electrochemical performance. It was found that the NaOH‐activated electrode material (C‐NaOH) exhibited a high specific capacitance of 199 F g−1 at a current density of 0.5 A g−1 thanks to its large surface area along with large pore volume. In the two‐electrode system, the symmetric SC assembled by C‐NaOH electrodes delivered an energy density of 4.7 Wh/kg at a power density of 127 W/kg and maintained 3.9 Wh/kg at a power density of 1560 W/kg. Another outcome of this study was that the Na2S2O3‐assisted activating agent could introduce heteroatom into the carbon framework, which contributes to pseudocapacitance behavior of electrodes. Overall, the alternative activating strategy could provide a high‐performance carbon electrode and may offer a pathway for an advanced energy storage technology.

A blood component production–inventory problem with preparation method combination and ABO compatibility

We consider the component dependence resulting from each preparation method consistently outputting a particular component combination in the integrated blood component production–inventory problem in a blood center. We first formulate a Markov decision process that comprehensively considers the alternative preparation methods, ABO compatibility, varying age-based inventories, stochastic supply of whole blood, and stochastic demand for components. Then, an approximate dynamic programming algorithm with the interval–adaptive and myopic-learning acceleration approaches is proposed to solve the problem. It performs well in the improvements of both the precision and learning speed. The numerical study displays the sophisticated optimal inventory levels and issuance policies of the blood components. We show that an integrated, operational production-inventory modeling is more capable of dealing with the interaction among the dependent outputs and their differentiated compatibilities and perishabilities. Moreover, the different substitution strategies (i.e., push and pull) are verified to provide similar overall supply levels while causing slight differences in other aspects. Further suggestions for specific components are also provided.

Inclusion of small intestinal absorption and simulated mucosal surfaces further improve the Mucosal Simulator of the Canine Intestinal Microbial Ecosystem (M-SCIME™)

While a large set of in vitro models are available to study the effects of specific food ingredients (e.g. pre- and probiotics) on the human gut microbiome, the availability of such models for companion animals is limited. Since improving gut health of such animals is an emerging research field, the Simulator of the Canine Intestinal Microbial Ecosystem (SCIME™) was recently developed and validated with in vivo data. The current study presents a further improvement of this model by using an alternative method for feed preparation, i.e. by administering digestive enzymes to mimic upper gastro-intestinal digestion followed by a dialysis approach to mimic small intestinal absorption. As opposed to the previously implemented method, this resulted in a more optimal simulation of protein digestion and absorption. Further, upon entrance in the colon, increased production of the health-promoting butyrate and lower levels of Lactobacillus spp. and Bifidobacterium spp. were observed, which corresponded better with obtained in vivo data. A second model improvement consisted of the implementation of a mucosal environment to not only simulate luminal but also mucosal microbiota. In consistency with the human model for which this technology was previously validated, it was found that for all canine microbiota mucin beads were enriched with members of the Lachnospiraceae (~ Clostridium cluster XIVa), a family containing multiple well-known butyrate producers. The SCIME™ was thus upgraded to a so-called Mucosal SCIME™ (M-SCIME™). In conclusion, the current study presents improvements of the SCIME™, further increasing the relevance of obtained data with this in vitro model for dogs.

Tunable Electrode Architectures for La0.8Sr0.2Fe1-XTixO3- δ Based Symmetrical Solid Oxide Fuel Cells

The efficiency of SOCF electrodes can be improved by optimizing the microstructure from alternative preparation methods, such as infiltration and nanostructured electrodes deposited at low temperature. Recent studies have demonstrated that spray-pyrolysis deposition is a versatile method to obtain nanostructured electrodes with improved performance in comparison with conventional electrodesprepared at high sintering temperatures. Among the different electrodes studied in the last few year, titanium-doped ferrites are one of the most promising because of their high redox stability and great electrochemical performance in both oxidizing and reducing conditions2,3. In this work, (La0.8Sr0.2)0.95Fe1-xTixO3- δ (x=0.2, 0.4) perovskites, hereafter labelled as LSFT02 and LSFT04, respectively, with different architectures were obtained by spray-pyrolysis deposition and they were tested as symmetrical electrodes for solid oxide fuel cell (SSOFC). The electrodes were deposited on as-prepared YSZ pellets and porous Ce0.9Gd0.1O1.95, preciously fixed on the electrolyte. A nanocomposite electrode was also prepared in a single step onto YSZ. The precursor solution containing the corresponding nitrates and etilendiaminetetraacetic acid (EDTA) as a complexing agent in a 25% molar ratio in Milli-Q water with a concentration of 0.025 M, was sprayed directly onto the electrolyte. The temperature deposition, time and flow rate was optimized to 325 ºC, 1 h and 20 mL min-1, respectively. After the deposition, the samples were calcined at 800 ºC for 1h to achieve crystallization. The structural characterization by XRD revealed that both LSFT02 and LSFT04 are nanocrystalline compounds without any secondary phases after annealing in air and reducing conditions. Figure 1 shows SEM images of the different electrode architectures cross-section at different magnifications. The electrodes deposited into the CGO backbone consists of a porous backbone (10 µm) coated with a layer of LSFT nanoparticles (∼50 nm of diameter) at 800 ºC (Fig. 1a). The HAADF-STEM images of the nanocomposite material showed a high homogeneity and particle size as low as 50 nm at 1000 ºC The electrochemical properties of the symmetrical cells were tested by impedance spectroscopy. The polarization resistance (Rp) in air of LSFT0.2 and LSFT0.4 impregnated CGO backbone by spray pyrolysis (SP) decrease from 1.19 and 8.84 Ω·cm2 to 0.23 and 0.67 Ω·cm2 at 700 ºC, respectively, when compared with the powders obtained by freeze drying precursor method. The similar behavior observed for both compositions confirmed that the increase of the TPB length, highly improves the electrochemical performance. Same results were obtained for the nanocomposite architecture. On the other hand, the Rp values in H2 for LSFT04 are slightly lower when compared with LSFT02, 0.21 and 0.35 Ω·cm2 at 700 ºC, respectively, fact that could be explained by the great efficiency of Ti-doped electrodes in reducing conditions at high temperature. In other to further improving the electrochemical performance, LSFT02 was doped with Ni and Ru, infiltrated into the CGO backbone and tested as SSOFC. The electrochemical performance in H2 improves substantially for the Ni-doped sample, achieving 0.09 Ω·cm2 at 750 ºC, which is one of the lowest ASR values for related materials, mainly attributed to the Ni0 nanoparticle exsolution combined with an advance microstructure configuration. The influence of d.c. bias in a 3-probe configuration was studied under cathodic and anodic polarization in symmetrical cells in both oxidizing and reducing conditions. The results revealed a considerable decrease on the LF process, attributed to surface diffusion and/or charge transfer in the electrode. The study of performance of the different architectures electrodes in real SOFC conditions are currently in process, but high maximum power densities are expected due to the low ASR values achieved.

Outcomes of Thyrotropin Alfa Versus Levothyroxine Withdrawal-Aided Radioiodine Therapy for Distant Metastasis of Papillary Thyroid Cancer.

Background: Thyrotropin alfa (rhTSH) is not currently approved by the Food and Drug Administration or European Medicines Agency for the preparation of radioactive iodine therapy (RAIT) in patients with distant metastatic papillary thyroid cancer (PTC). There are only a few studies comparing rhTSH with levothyroxine withdrawal (LTW) in this context. Our main aim was to compare the two methods of RAIT preparation in terms of avidity and structural/biochemical response in distant metastatic PTC. We also intended to evaluate whether the two methods of RAIT preparation represented independent prognostic factors for progression-free survival (PFS) and disease-specific survival (DSS) in this subset of patients. Methods: We performed a retrospective analysis of all patients with PTC treated with RAIT for distant metastatic disease between 2006 and 2018. We included 95 PTC patients-27 (28.4%) had LTW and 68 (71.6%) had rhTSH for RAIT. Results: The two groups presented similar clinicopathological characteristics, except for median age at PTC diagnosis, which was higher in the rhTSH group (p = 0.001), but the median age at first RAIT for distant metastatic disease was not different between the two methods of preparation, 63 years old (interquartile range [IQR] 23) in the LTW group versus 70 (IQR 26.75), p = 0.06. Avidity was similar between the two groups (p = 0.973). Median estimate PFS (p = 0.076) and DSS (p = 0.084) were also similar between LTW and rhTSH. Regarding RAIT-related side effects, only 1 (3.7%) patient and 5 (7.4%) patients in the LTW and rhTSH groups, respectively, reported sialadenitis (p = 0.670). Conclusions: There were no differences between the two methods of RAIT preparation regarding avidity and clinical response. rhTSH may be used as an alternative method of preparation for RAIT in patients with known distant lesions, as it presents similar clinical outcomes to LTW and a good safety profile.

Surface Observation of Laser-treated Carbon Steel and Application of Laser Ccleaning for Corroded Steel Member

A newly developed laser system is adopted in this study as a surface preparation method for corroded steel structures. To investigate the thermal effects of laser beam on steel material, carbon steel plates are treated by two different laser processing parameters. Then the surface condition, heat-affected zone, and iron oxide on laser-treated specimens are evaluated using optical microscope, SEM-EDX, and XRD. Moreover, a severely corroded steel member was used as laser irradiation target to verify the cleaning effects of laser beam. Results show that surface morphologies are varied according to laser processing parameters. Due to thermal effects, iron oxide was formed after laser irradiation, and higher laser power induced deeper heat-affected zone. The application of laser treatment for corroded steel member showing desirable surface cleanliness after laser irradiation. The laser surface treatment could be an alternative surface preparation method for steel structures in the construction field.

Engineering photo-controllable fragrance release with flash nanoprecipitation

Controllable profragrance nanoparticles are in great demand for long-lasting scent in flavor and fragrance industries. However, the practical applications of controllable fragrance release are limited by the non-tunable size, structural heterogeneity and poor reproducibility. Herein, a coumarin-derived phototrigger (CM-OH) is covalently conjugated with alcohol fragrances to obtain the corresponding profragrances (CM-R) which enable to release fragrances under the light controlling conditions. Furthermore, we introduce a new engineering strategy to construct fine tunable and highly uniform profragrance nanoparticles with flash nanoprecipitation (FNP) technology, which features commercial available amphiphilic pluronic F127 polymers by encapsulation of photo-activatable profragrances CM-R in hydrophobic cores to enhance the long-lasting photo-controllable fragrance release. With the assistance of FNP technology, amphiphilic pluronic polymer and profragrances CM-R in organic solution are instantaneously mixed and subsequently precipitated in the multi-inlet vortex mixer (MIVM), thus obtaining the pluronic F127-encapsulated profragrance nanoparticles with good homogeneity. Compared to the traditional thermodynamic encapsulation method, the novel kinetic FNP technology can not only tune the size of profragrance nanoparticles with narrow distribution, but also distinctly improve the batch-to-batch reproducibility, which affords an alternative method for scale-up preparation of amphiphilic profragrance nanoparticles in precisely controllable fragrance delivery system.

Active Immunization with Pasteurella multocida Lysate Elicits Antibody that Protects Rabbits against Virulent Pasteurella multocida and Protects Mice by Passive Immunization

Background: Pasteurellosis is an economically important disease of livestock worldwide and vaccination is effective mean to control the disease outbreaks. One of alternative method for vaccine preparation could be the use of lytic phages as bacterial inactivating agents and employing “phage lysate immunogen” as an immunizing agent. Therefore, the study was undertaken to explore the protective immune response of novel phage lysate vaccine against Pasteurella multocida. Methods: A phage lysate vaccine of Pasteurella multocida was prepared using isolated lytic phage and subjected to vaccine response study in rabbits. In this experiment, two mouse fixed-dose of lysate was used and the prophylactic efficacies of lysates were evaluated in rabbits by passive mouse protection test (PMPT), western blotting and direct virulent challenge.Result: Passive transfer of antibodies to mice using post-immunization sera of rabbits protected the animals against the challenge with A: 1 strain (75%) and B: 2 strain (50%). In western blotting, a total number of 4 bands were observed in the region between 130 kDa to 25 kDa in the protein of the phage lysate. The study suggested the significance increase in humoral immunity by phage lysate in murine Pasteurellosis.

Immunohistochemical and Genetic Labeling of Hairy and Glabrous Skin Innervation.

Cutaneous innervation is an essential component of the mammalian sensory nervous system. During development, genetically and morphologically diverse subtypes of sensory neurons use distinct molecular pathways to innervate end organs or form free nerve endings in glabrous and hairy skin. Peripheral neurons can be damaged by acute injury or degenerate due to chronic conditions including diabetes and chemotherapy, leading to peripheral neuropathy. The analysis of skin and cutaneous innervation can be applied to many research endeavors, from developmental neuroscience to pharmaceutical testing. Due to the natural hydrophobicity and heterogenous makeup of the skin (dense, keratinized cells as well as sparse, extracellular-matrix-bound cells), its histological analysis presents unique challenges compared to that of many other tissues. This series of protocols describes histological methods for generalized immunohistochemistry and subtype-specific genetic labeling of sensory neurons in mouse skin in both whole-mount and section formats. We provide detailed methodology of tissue preparation for hairy and glabrous skin, several types of labeling, and counting of hair follicles in flat-mounted mouse skin. © 2021 Wiley Periodicals LLC. Basic Protocol 1: Cryosectioning and immunostaining of mouse hairy skin Alternate Protocol 1: Alternate method for preparation and fixation of mouse hairy skin Basic Protocol 2: Sectioning of mouse paw glabrous skin Basic Protocol 3: Whole-mount immunolabeling of mouse skin Basic Protocol 4: Sparse labeling of skin-innervating neurons with a Cre-dependent membrane-bound alkaline phosphatase reporter Alternate Protocol 2: Sparse labeling of skin-innervating neurons with a Cre-dependent fluorescent reporter Basic Protocol 5: Oil Red O staining of skin.

Electrochemical Reduction of CO2 on Flame Annealed Cu

AbstractSurface modification of metallic Cu by conventional oxidation and an alternative method of oxidation using flame annealing and its influence on electrochemical reduction (ECR) of CO2 are reported in this study. The ECR of CO2 in aqueous KCl electrolyte yielded methane, ethane, ethylene, and hydrogen as the major products. The faradaic efficiency of ethane obtained at −1.2 V vs NHE for flame‐annealed Cu (34 %) was comparable to the conventionally oxidised Cu (40 %), while bare Cu yielded methane (10 %). The metal–metal oxide interface on the electrode aids in the formation of C2‐based products. Flame annealing can be regarded as an alternative electrode preparation method for C2 product formation, with its merits in high specific surface area, self‐rejuvenating mode on deactivation and ease of preparation.

Marine Algae Incorporated Polylactide Acid Patch: Novel Candidate for Targeting Osteosarcoma Cells without Impairing the Osteoblastic Proliferation.

Biodegradable collagen-based materials have been preferred as scaffolds and grafts for diverse clinical applications in density and orthopedy. Besides the advantages of using such bio-originated materials, the use of collagen matrices increases the risk of infection transmission through the cells or the tissues of the graft/scaffold. In addition, such collagen-based solutions are not counted as economically feasible approaches due to their high production cost. In recent years, incorporation of marine algae in synthetic polymers has been considered as an alternative method for preparation grafts/scaffolds since they represent abundant and cheap source of potential biopolymers. Current work aims to propose a novel composite patch prepared by blending Sargassum vulgare powders (SVP) to polylactide (PLA) as an alternative to the porcine-derived membranes. SVP-PLA composite patches were produced by using a modified solvent casting method. Following detailed material characterization to assess the cytocompatibility, human osteoblasts (HOBs) and osteosarcoma cells (SaOS-2) were seeded on neat PLA and SVP-PLA patches. MTT and BrdU assays indicated a greater cytocompatibility and higher proliferation for HOBs cultured on SVP-PLA composite than for those cultured on neat PLA. SaOS-2 cells cultured on SVP-PLA exhibited a significant decrease in cell proliferation. The composite patch described herein exhibits an antiproliferative effect against SaOS-2 cells without impairing HOBs’ adhesion and proliferation.

Simultaneous formation of inclusion complex and microparticles containing Albendazole and β-Cyclodextrin by supercritical antisolvent co-precipitation

Albendazole (ABZ) is an effective anthelmintic and an anticancer candidate. Due to the low oral bioavailability associated with its poor aqueous solubility, high doses are required, and dose-related side effects are reported. To enhance ABZ dissolution different formulation approaches were proposed, among others, its combination with cyclodextrins. In this work, co-precipitation of β-cyclodextrin and ABZ was performed by supercritical antisolvent technique as an alternative preparation method. The operating temperature and pressure of the experiments were selected by thermodynamic modeling with the purpose of obtaining a miscible solution between solvent mixture (DMSO + acetone) and CO2. Precipitated microparticles were characterized by spectroscopic, thermal, and crystallographic analysis in order to demonstrate the formation of a new solid form. The characterization evidenced that tautomer II of ABZ was obtained by precipitation in supercritical CO2 medium. The change of the crystalline phase was discussed in light of the results reported in the literature. Composite microparticles were obtained with a mean diameter ranging from 0.45 to 1.4 μm. An increase of about 4 times in the ABZ dissolution rate was measured for the particles with a 3:1 ABZ:β-cyclodextrin molar ratio with respect to the corresponding physical mixture and pure ABZ obtained by the same method. The dissolution improvement was attributed to the formation of the inclusion complex and a synergetic effect between both components, rather than the increase obtained for the change of ABZ to polymorphic form II.

A revision of bird skin preparation aimed at improving the scientific value of ornithological collections

The methods used to preserve bird skins in museums have a potentially crucial impact on the feasibility and use of these specimens as a source of biological knowledge, although this subject is rarely broached. Study skins of birds are usually prepared with folded wings and straight legs to facilitate storage in the collection; yet, this method can hamper the measurement and examination of certain important features such as wing-feather moult. To make consultation easier for ornithologists, alternative preparation methods such as the splitting of wings and tarsi from the rest of the animal have been proposed by curators. Our aim was to study whether or not preparing bird specimens with spread limbs makes consultation simpler. First, we used two different methods to prepare two specimens each of two common European passerine species: (1) ‘traditional’ (folded wings and straight tarsi) and (2) ‘spread’ (limbs spread on one side of the body). Then, we asked 22 experienced ornithologists to identify moult limits and take three biometric measurements (wing chord, length of the third primary feather and tarsus length) from all four specimens. Subsequently, we asked which preparation method they preferred for obtaining data. The ‘spread’ preparation was preferred for moult, third primary feather length and tarsus length, whilst the ‘traditional’ preparation was preferred for wing chord. Data obtained from the folded and spread preparations were very highly repeatable within each method but only moderately to highly repeatable between methods. One of the handicaps with the ‘spread’ preparation is the increase in storage space required, a factor that should be taken into account before it is employed. Nevertheless, this specimen preparation technique can greatly facilitate consultation and therefore improve the scientific value of ornithological collections.

Specimen Preparation and Observations of Magnaporthe oryzae Appressorial Cells Under Electron Microscopy.

Electron microscopy (EM) allows characterization of the morphology and ultrastructure of a cell. However, challenges concerning cryo sample fixation are still one of the main roadblocks to its widespread adoption. In this protocol, we describe two alternative EM preparation methods employed to study Magnaporthe oryzae appressoria on artificial hydrophobic surfaces.

Uniform Supported Metal Nanocrystal Catalysts Prepared by Slurry Freeze-Drying

Colloid immobilization is an established way to load metal nanocrystals (NCs) onto solid supports to make heterogeneous (photo)catalysts. The use of preformed colloidal NCs enables excellent control of NC composition, size, and shape compared to alternative catalyst preparation methods, but this approach often suffers from uncontrolled NC aggregation, nonuniform NC loading, and strongly bound ligands on the NC surface that inhibit catalytic activity. Here, we show that freeze-drying of aqueous slurries of gold NCs and various powdered supports (cellulose, TiO2, Al2O3, SiO2, carbon) produces highly uniform, well-dispersed supported NCs over a wide range of NC loadings (to at least 20 wt %) and batch sizes (to at least 1 g). Rinsing supported citrate-capped NCs with water removes citrate ligands to yield active gold surfaces without the need for high-temperature calcination. The reduction of Pt4+ to Pt0 and 4-nitrophenol to 4-aminophenol on the surface of the supported NCs is used to demonstrate the activity of these catalysts. Slurry freeze-drying offers superior product uniformity, reproducibility, and scalability and should prove useful as a simple and general method for making supported NC catalysts, including plasmonic photocatalysts.