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In this study, we aimed to describe the morphological and molecular characteristics of Austroglycyphagus geniculatus (Acari: Glycyphagidae) breeding in fodder. Flour and corn-crushed fodder samples were collected from a small fodder processing mill in Wuhu, Anhui province, China. The detection rate of A. geniculatus was 100% in six samples, and the breeding density was 1.44 mites/g. Under an optical microscope, we observed that the mite body was oval and small in size. The epidermis of the mite was coated with fine particles. We found two obvious, large, and red lateral ventral glands on either side of hysterosoma. The gene sequences for internal transcribed spacer (ITS) and mitochondrial cytochrome oxidase 1 (COX 1) of A. geniculatus were amplified and uploaded to the GenBank nucleotide sequence database. To the best of our knowledge, this is the first study to report the detailed description of the morphological and molecular characteristics of A. geniculatus. The results of phylogenetic relationships obtained from the ITS and COX 1 support the classification statuses of A. geniculatus to the family Glycyphagidae based on the morphological classification. Our study provides morphological and molecular data for inferring phylogenetic relationship of A. geniculatus. [ABSTRACT FROM AUTHOR]

Makinoella Okada is a genus of coccoid green algae belonging to the family Oocystaceae with typical morphological characteristics. Reports to date included only one type species. Since the genus is rarely reported, there is a lack of taxonomic research. In this study, 17 strains of this genus were collected from several different places in China, and their taxonomic studies were conducted based on morphological and molecular phylogenetic analysis. The phylogenetic results based on the analysis of ITS, chloroplast genes rbcL and tufA showed that the genus was divided into two branches. One of the branches comprised newly collected algae. Compensatory base changes (CBCs) and hemi-compensatory base changes (hemi-CBCs) within the secondary structure of the ITS-2 confirmed the branches as two species. Compared with the type species of Makinoella tosaensis, the cell size of this new branch was only about 50%, and included 2–4 colonial cells. Therefore, based on the smaller cell size, simpler colony composition, independent phylogenetic position and CBCs and hemi-CBCs, we suggest that the new clade should be designated as a new taxon of Makinoella, namely Makinoella parva. Among the four molecular markers using in this study, the rbcL and newly introduced ITS are recommended for species separation, which can help further studies to revise the species and generic concepts of the family. [ABSTRACT FROM AUTHOR]

Electromagnetic punching (EMP) is a dynamic, high-energy and high-speed hole-processing method. In this paper, the EMP specimens under different discharge energies (11–19 kJ) was prepared. By numerical and experimental methods, the deformation characteristic was analyzed, and hole-quality assessments (including morphology observation, dimensional measurements and microhardness test) were implemented. Results showed that the deformation process of sheet consisted of electromagnetic induction, elastic deformation, plastic deformation and separation stage, and the duration of the entire process was within 100 μs. For 11–15 kJ, the sheet had not completed the entire EMP process (no separation stage), and the deformation degree was aggravated with the increase of discharge energy. For 16 kJ, the incomplete punching occurred owing to the insufficient of electromagnetic force and uneven force. As discharge energy continued to increased, the dimensional accuracy of punching improved, the proportion of rollover zone (η) decreased, the slant angle of fracture zone (β) increased (gradually perpendicular to the sheet plane), the surface morphology of hole wall was more regular, and the micro hardness value of cross section increased, indicating that the punching quality of punched hole was improved. In addition, this work can provide a scientific guidance for the engineering application of EMP technology in automobile industry. [ABSTRACT FROM AUTHOR]

Abstract Background Prunus mume is an early spring flower of Rosaceae, which owns high application value in gardens. Being an excellent ornamental trait, the double flower trait has always been one of the important breeding goals of plant breeders. However, the key regulatory genes of double flower traits of P. mume are still unclear at present. Results The floral organs’ morphological differences of 20 single and 20 double flower cultivars of P. mume were compared firstly. And it was found that double flower trait of P. mume were often accompanied by petaloid stamen, multiple carpels and an increase in the total number of floral organs. Then, transcriptome sequencing of two representative cultivars P. mume ‘Danban Lve’ and P. mume ‘Xiao Lve’ were conducted at 3 Stage of flower bud development with distinct morphological differentiation. 3256 differentially expression genes (DEGs) were detected, and 20 candidate genes for double flower trait of P. mume were screened out including hub genes PmAP1–1 and PmAG-2 based on DEGs function analysis and WGCNA analysis. And it was found that epigenetic and hormone related genes may also play an important role in the process of double flower. Conclusions This study suggested that the double flower trait of P.mume is more like accumulation origin based on morphological observation. 20 genes and co-expression network related to the formation of double flower P. mume were preliminarily screened through transcriptomics analysis. The results provided a reference for further understanding of the molecular mechanism of double flower trait in P. mume.

High flow (hf)-modified polypropylene (PP) fibers and glass filaments (GFs) were made into webs, which were then laminated orthogonally and needle punched to make GF/PP-hf preforms. These preforms were then hot pressed to produce GF/PP-hf composites. Similarly, GFs and nonmodified PP were made into GF/PP composites with the aforementioned process to serve as the control group. The structure, morphology, and mechanical performances (i.e. tensile, bending, and impact strength) of GF/PP and GF/PP-hf composites were characterized and tested using differential scanning calorimeter and dynamic mechanical analysis. The test results showed that the GF/PP-hf composites are composed of reinforcing filaments at a weight ratio of 43.40% and an average length of 22.9 mm. Consequently, they had advantages of high fiber content, long fiber length, and adjustable fiber orientation. Compared to GF/PP composites, GF/PP-hf composites exhibited good dispersion of GFs in the matrices, good bonding between filaments and the matrix, and a relatively lower porosity factor of 2.92%. Moreover, the glass transition temperature and crystallinity were improved by 15.2°C and 10.42%, respectively. When the temperature was lower than 160°C, GF/PP-hf composites preserved a higher energy storage modulus and a lower loss factor. Furthermore, GF/PP-hf composites exhibited good static mechanical properties, including the tensile strength of 118 MPa, the tensile modulus of 5830 MPa, the bending strength of 180 MPa, the bending modulus of 780 MPa, and the impact strength of 33 KJ m−2, which are 30, 29.6, 78.2, 68.3, and 32%, respectively, higher than those of the control group. [ABSTRACT FROM AUTHOR]

Background: Prunus mume is an early spring flower of Rosaceae, which owns high application value in gardens. Being an excellent ornamental trait, the double flower trait has always been one of the important breeding goals of plant breeders. However, the key regulatory genes of double flower traits of P. mume are still unclear at present. Results: The floral organs' morphological differences of 20 single and 20 double flower cultivars of P. mume were compared firstly. And it was found that double flower trait of P. mume were often accompanied by petaloid stamen, multiple carpels and an increase in the total number of floral organs. Then, transcriptome sequencing of two representative cultivars P. mume 'Danban Lve' and P. mume 'Xiao Lve' were conducted at 3 Stage of flower bud development with distinct morphological differentiation. 3256 differentially expression genes (DEGs) were detected, and 20 candidate genes for double flower trait of P. mume were screened out including hub genes PmAP1–1 and PmAG-2 based on DEGs function analysis and WGCNA analysis. And it was found that epigenetic and hormone related genes may also play an important role in the process of double flower. Conclusions: This study suggested that the double flower trait of P.mume is more like accumulation origin based on morphological observation. 20 genes and co-expression network related to the formation of double flower P. mume were preliminarily screened through transcriptomics analysis. The results provided a reference for further understanding of the molecular mechanism of double flower trait in P. mume. [ABSTRACT FROM AUTHOR]

Due to extensive morphological plasticity, the taxonomy of Cladophora species remains unclear. As one of the widely distributed species, C. gracilis was reported to hold many varieties, which make it difficult to identify the species. This study explored the morphology diversity of nine C. gracilis samples collected along the coast of western Yellow Sea. Some samples showed extremely varied characteristics, by which one cannot classify them correctly. Hence, 18S rDNA and nuclear ribosomal DNA internal transcribed spacer regions (ITS) sequences were employed to delimit species. For 18S rDNA, sequence similarity ranged from 99.6% to 100%. For ITS region, the similarity ranged from 98.7% to 100%. Molecular data strongly suggested that the morphologically heterogeneous samples were actually the same species. Characteristics comparison of the samples revealed that the taxonomy criteria including branching pattern and density, thallus color, height and texture varied widely, influenced by environmental conditions and age of alga. Besides, cell dimensions, as the relatively stable criterion, also exhibited intraspecific variance. Successful application of 18S rDNA and ITS sequences indicated that molecular method can be a powerful assistant as DNA barcodes to traditional morphology taxonomy. [ABSTRACT FROM AUTHOR]

Gold coating is a general operation that is generally applied on non-conductive or low conductive materials, during which the morphology of the materials can be examined by scanning electron microscopy (SEM). However, fatal deficiencies in the materials can result in irreversible distortion and damage. The present study directly characterized different low conductive materials such as hydroxyapatite, modified poly(vinylidene fluoride) (PVDF) fiber, and zinc oxide nanopillar by cold field emission scanning electron microscopy (FE-SEM) without a gold coating. According to the characteristics of the low conductive materials, various test conditions, such as different working signal modes, accelerating voltages, electron beam spots, and working distances, were characterized to determine the best morphological observations of each sample. [ABSTRACT FROM AUTHOR]

High temperatures and humidity could alter the field-dependent rheological properties of MR materials. These environmental phenomena may accelerate the deterioration processes that will affect the long-term rheological reliability of MR materials such as MR elastomer (MRE). This study therefore attempts to investigate the field-dependent rheological characteristics of MRE with corroded carbonyl iron particles (CIPs). The corroded CIPs were treated with hydrochloric acid (HCl) as a way of providing realistic environments in gauging the CIPs reaction towards the ambient conditions. The corroded CIPs along with silicone rubber as a matrix material were used in the fabrication of the MRE samples. To observe the effect of HCl treatment on the CIPs, the morphological observations of MREs with non-corroded and corroded CIPs were investigated via field emission scanning electron microscopy (FESEM), energy-dispersive x-ray spectroscopy (EDX) and x-ray diffractometer (XRD). In addition, the magnetic properties were examined through the vibrating sample magnetometer (VSM), while the field-dependent rheological characteristics such as the storage modulus of MRE with the corroded CIPs were also tested and compared with the non-corroded CIPs. The results showed that the corroded CIPs possessed hydrangea-like structures. In the meantime, it was identified that a sudden reduction of up to 114% of the field-dependent MR effect of MRE with the corroded CIPs was observed as a result of the weakened interfacial bonding between the CIPs and the silicon in the outer layers of the CIPs structure.

Steam explosion pulping was evaluated for oil palm empty fruit bunches fiber. The fiber morphology was observed by SEM and TEM. Results indicated that lignin was molten and the cell wall damaged after the steam explosion pulping and that the fiber was partly separated at the same time. The results of handsheet tests showed that the steam exploded pulp had a high yield (78.2%), good physical properties (especially for ring crush 8.6 N•m/g), and low effluent load (SS=910 mg/L; BOD5=3952 mg/L; CODCr=8140 mg/L). The SEP pulp from oil palm EFB fiber was very suitable for packaging paper when combined with American OCC pulp.

This paper investigates the field-dependent rheological properties of magnetorheological (MR) fluid used to fill in MR dampers after long-term cyclic operation. For testing purposes, a meandering MR valve was customized to create a double-ended MR damper in which MR fluid flowed inside the valve due to the magnetic flux density. The test was conducted for 170,000 cycles using a fatigue dynamic testing machine which has 20 mm of stroke length and 0.4 Hz of frequency. Firstly, the damping force was investigated as the number of operating cycles increased. Secondly, the change in viscosity of the MR fluid was identified as in-use thickening (IUT). Finally, the morphological observation of MR particles was undertaken before and after the long-term operation. From these tests, it was demonstrated that the damping force increased as the number of operating cycles increases, both when the damper is turn on (on-state) and off (off-state). It is also observed that the particle size and shape changed due to the long operation, showing irregular particles.

Soluble functional copolyimides are of great interest due to their excellent thermal properties and solubility, and the ability to adapt their properties to a wide range of special applications. Therefore, a novel poly(amide-ester-imide)s (PAEI)s was obtained by step-growth polymerization of several optically active diacids (3a–3d) with diol, ‘N,N′-(1,3,5,7-tetraoxo-5,7-dihydropyrrolo[3,4-f]isoindole-2,6(1H,3H)-diyl)bis(4-hydroxybenzamide)’ (4) via tosyl chloride, pyridine, andN,N-dimethylformamide (DMF) as a condensing agent. The obtained polymers were characterized by FT-IR, and1H-NMR spectroscopy. Also, their physical properties including X-ray diffraction, elemental analysis, specific rotation techniques, field emission scanning electron microscopy (FE-SEM), and thermogravimetric analysis (TGA) were examined. These PAEIs with inherent viscosities in the range of 0.22–0.33 dL/g showed excellent solubility in various solvents such asN-methyl-2-pyrrolidinone,N,N-dimethylacetamide, and DMF. TGA showed that all polymers were stable, with 10% weights loss recorded above 380 °C in nitrogen atmosphere. Preliminary tests on the films of PAEI indicated that these materials are brittle. The FE-SEM of the above-mentioned PAEIs confirmed that these macromolecules show spherical morphology. [ABSTRACT FROM PUBLISHER]

In this paper, multi-formation and multi-dissociation experiments of methane hydrate in quartz sands (6.5–355 μm) were carried out in a high-pressure visible reactor. The results showed that the cumulative amount, saturation and initial formation rate of hydrate increased with the size of sand particles decreasing, and also increased with the cycles of hydrate formation under the equal experimental time. When the sand particles ranged from 6.5 to 48 μm, the hydrate saturation reached the maximum of 59.5%. Performing experiments with sands of 109–120 μm, the hydrate saturation at the three repetitive formations were 26.2%, 39.3% and 41.7%, respectively. Besides, the hydrate dissociation process was affected by the initial hydrate saturation and the way of its occurrence, which suggested that a higher hydrate saturation would lead to a longer dissociation. The morphology observations indicated that the hydrate formation in the quartz sand mainly existed in the form of pore-filling, and the formation process was actually a dynamic process accompanied with dissociation. Furthermore, in the experiment of layered accumulations, the hydrate firstly formed in the layer of large particle sand, and the forming process of fracture-type hydrate was observed in the layer of 6.5–48 μm particle sand. The results of this work may provide a new insight on the formation and dissociation laws of hydrate and some useful information for the natural hydrate exploration. [Display omitted] • Hydrate formation and dissociation cycles in four particle-sized sands was experimented. • Methane hydrate formation, re-formation, and dissociation was conducted. • Formation process of fracture-type hydrate was observed. • Delay of heat transferring fluctuated the dissociation process was proposed. • Impact of initial saturation on hydrate dissociation time and rate was studied. [ABSTRACT FROM AUTHOR]

High temperatures and humidity could alter the field-dependent rheological properties of MR materials. These environmental phenomena may accelerate the deterioration processes that will affect the long-term rheological reliability of MR materials such as MR elastomer (MRE). This study therefore attempts to investigate the field-dependent rheological characteristics of MRE with corroded carbonyl iron particles (CIPs). The corroded CIPs were treated with hydrochloric acid (HCl) as a way of providing realistic environments in gauging the CIPs reaction towards the ambient conditions. The corroded CIPs along with silicone rubber as a matrix material were used in the fabrication of the MRE samples. To observe the effect of HCl treatment on the CIPs, the morphological observations of MREs with non-corroded and corroded CIPs were investigated via field emission scanning electron microscopy (FESEM), energy-dispersive x-ray spectroscopy (EDX) and x-ray diffractometer (XRD). In addition, the magnetic properties were examined through the vibrating sample magnetometer (VSM), while the field-dependent rheological characteristics such as the storage modulus of MRE with the corroded CIPs were also tested and compared with the non-corroded CIPs. The results showed that the corroded CIPs possessed hydrangea-like structures. In the meantime, it was identified that a sudden reduction of up to 114% of the field-dependent MR effect of MRE with the corroded CIPs was observed as a result of the weakened interfacial bonding between the CIPs and the silicon in the outer layers of the CIPs structure. [ABSTRACT FROM AUTHOR]

This paper investigates the field-dependent rheological properties of magnetorheological (MR) fluid used to fill in MR dampers after long-term cyclic operation. For testing purposes, a meandering MR valve was customized to create a double-ended MR damper in which MR fluid flowed inside the valve due to the magnetic flux density. The test was conducted for 170,000 cycles using a fatigue dynamic testing machine which has 20 mm of stroke length and 0.4 Hz of frequency. Firstly, the damping force was investigated as the number of operating cycles increased. Secondly, the change in viscosity of the MR fluid was identified as in-use thickening (IUT). Finally, the morphological observation of MR particles was undertaken before and after the long-term operation. From these tests, it was demonstrated that the damping force increased as the number of operating cycles increases, both when the damper is turn on (on-state) and off (off-state). It is also observed that the particle size and shape changed due to the long operation, showing irregular particles. [ABSTRACT FROM AUTHOR]