Ultrasonic treatment combined with resveratrol modification was used to improve banana starch’s solubility, thermal stability, and digestion resistance. The solubility and freeze-thaw stability of the modified starch complex significantly increased. The oil-absorption capacity increased by 20.52%, and the gelatinization temperatures increased from 64.10–73.92 °C to 70.77–75.83 °C. The storage modulus (G′) and loss modulus (G″) increased after ultrasound and resveratrol treatment, and the proportion of viscosity was increased after composition with resveratrol. Additionally, the in vitro digestibility decreased from 44.12% to 40.25%. The modified complexes had release-control ability for resveratrol. X-ray diffraction (XRD) and Fourier transform infrared (FT-IR) spectroscopy demonstrated that complex structures became more compact and organized, whereas crystalline patterns were unchanged. Scanning electron microscopy (SEM) showed that the resveratrol modification caused physical change on the granular surface by creating pores and fissures. The findings can help develop antioxidant functional foods using banana starch. Bananas are an essential tropical crop and are listed as the fourth largest fruit crop by the Food and Agriculture Organization of the United Nations. Banana starch is the main component of green bananas. It has up to 60% resistant starch (RS), including starch and starchy products that cannot be digested in the human body’s small intestine. Instead, it can be fermented by gut microbiota in the colon . The phyHowever, native starch has low solubility in cold water, low thermal stability, and low resistance to regeneration. These properties limit the application of starch . TherefoResveratrol , a natural polyphenol, is abundant in red wine, peanuts, grape, and tomato peel. The benefits of resveratrol are its neuroprotective, anticancer, antioxidant, and anti-inflammatory properties . HoweverNevertheless, single polyphenol or ultrasonic treatment could affect the properties of starch. The combined effect of ultrasonic treatment with polyphenols on the properties of banana starch has not been reported. In this study, ultrasonic treatment combined with resveratrol modification was used to improve banana starch’s solubility, thermal stability, and digestion resistance. In addition, the physicochemical, in vitro digestibility, and release properties of resveratrol from the complexes were characterized. Furthermore, the mechanism of the effects of ultrasound treatment and resveratrol complexation on the properties of banana starch was investigated. Collectively, the results of this study could provide a new approach to developing functional foods using green-banana byproducts.Green banana (Musa AAA Cavendish subgroup cv. Nan tian huang), with a pericarp color index of 1 ), was provided by the Experimental Base of the Chinese Academy of Tropical Agricultural Sciences. Resveratrol was purchased from Shanghai Aladdin Bio-technology Co., Ltd. . Saliva α-amylase, pepsin, trypsin, amyloglucosidase, and porcine bile salt were purchased from Sigma-Aldrich Trading Co., Ltd. . The D-glucose assay kit (GOPOD Format K-GLUK) was purchased from Shanghai Megazyme Bio-technology Co., Ltd. . Other chemicals used in this experiment were of analytical grade.w/v) for 2 min. The homogenized mixture was centrifuged  at 5000 rpm for 10 min. The sediments were isolated and dried in an oven  at 45 °C for 6 h. The dried banana starch was ground into powder by a mortar  and screened through a 100 mesh sieve . The starch was stored in a brown reagent bottle and put in the freezer  at 4 °C for further use. The prepared banana starch was native starch and named NS.Banana starch was extracted according to the previous procedure . After gw/v) and treated using an ultrasonic processor  for 10 min in a pulsed mode. The ultrasound amplitudes were selected as 40%, 60%, 80%, and 100% and marked as U40S, U60S, U80S, and U100S, respectively. The sample was placed in an ice bath when operating to prevent the slurries’ temperature from rising. Then, the slurries were centrifuged  at 5000 rpm for 10 min, and the sediments were dried  at 45 °C for 6 h and ground by a mortar .The starch was dispersed in ultrapure water  I2 and 2.0% (w/w) KI in ultrapure water) in a tube. Iodine-binding-capacity (IBC) values of the sample and control (without resveratrol) were detected at 690 nm. The CI was calculated using Equation (1):reference is the absorbance value of the reference, and IBCsample is the absorbance value of the sample.The complex index (CI) was used to determine the degree of starch–resveratrol complex formation . The staw/v). The suspensions were heated at 50, 60, 70, 80, and 90 °C in a water-bath shaker  for 30 min. The mixture was centrifuged  at 4000 rpm for 10 min after natural cooling. The sediments were dried  at 105 °C to a constant weight. The S and SP were calculated as Equations (2) and (3), respectively:1 is the constant weight after drying, W0 is the initial weight of the starch sample, and W2 is the weight of the swollen starch.Guo et al.  was refe1 (g) and m2 (g) are the weight of original starch and the precipitate, respectively.The oil-absorption capacity (OAC) of the starch–resveratrol complexes was measured based on Wang et al. . Starch The freeze-thaw stability of the samples was analyzed based on the report of Zheng et al. . Brieflyo), peak temperature (Tp), end-set temperature (Tc), and enthalpy change (ΔH) of each sample were determined.Thermal properties of starch samples were determined using differential scanning calorimetry . Three milligrams of starch sample and ultrapure water (1:3) were mixed in DSC pans. Then, the sealed pans were equilibrated at 25 °C for 24 h. The samples were heated from 20 to 100 °C at 10 °C/min during DSC testing, and an empty pan served as the control. The onset temperature  and naturally cooled to 25 °C. A total of 1 mL of gelatinized starch paste was absorbed, and steady-state shear and dynamic oscillation (frequency sweep) analyses of the sample were carried out by a rotary rheometer .−1 at 25 °C. The data were fitted into Equation (6).n), and n is the flow-behavior index.The starch paste was placed on the rheometer plate using a parallel plate with a diameter of 40 mm and a gap of 1 mm. The sample’s shear stress (Pa) was measured with a shear rate of 0.1–200 sAfter the operation in In vitro digestibility of the starch samples was based on Ye et al. . Mouth, For the mouth phase, 50 mg of the starch samples were added to 10 mL of SSF containing α-amylase . Then, the suspension was adjusted to pH 6.8 and shaken in a water bath  for 2 min.For the gastric phase, the SGF  including pepsin (2000 U/mL) was mixed with the mouth-phase sample and adjusted to pH 3.0. Then, the suspension was shaken at 37 °C for 2 h at 100 rpm.For the small-intestine phase, the suspension (20 mL) obtained from the gastric phase was adjusted to pH 7.0. After that, 10 mL of SIF, 5.0 mL of a pancreatin (800 U/mL) and amyloglucosidase (15 U/mL) solution consisting of SIF, and 3.5 mL of bile extract (53.57 mg/mL) were mixed with the sample. Then, 0.15 mL NaOH (0.1 M) were adjusted to pH 7.0 and mixed with 1.35 mL of water to make up 20 mL. The suspension was shaken under the same conditions for an additional 150 min.i is the original amount of starch, and Gh is the amount of glucose produced. A constant of 0.9 was used to convert the molar mass from glucose to anyhydroglucose.The sample (0.5 mL) was taken after 2 min reaction time in the mouth phase (S2), after 30 min and 120 min reaction times in the gastric phase (G30 and G120), and after 10, 20, 60, 90, 120, and 150 min reaction times in the small-intestine phase (I10-I150) to measure the hydrolysis degree of the starch at each time. The content of glucose was determined via a D-glucose assay kit. Starch hydrolysis (%) was calculated by Equation (7):t (%) is the percentage of digestion at time t (min), C∞ (%) is the final percentage of digestion, k (min−1) is the starch-digestion-degree coefficient, and t is the reaction time. The logarithm-of-slope (LOS) analysis was determined through Equation (9) [Equation (8) was used to describe the kinetics of starch hydrolysis :(8)Ct=C∞tion (9) :(9)ln (dThe contents of rapidly digestible starch (RDS), slowly digestible starch (SDS), and RS in the samples were determined with Equations (10)–(12) :(10)RDS −1. The samples were blended with KBr powder and pressed into round tablets. They were then measured by FT-IR spectroscopy.The FT-IR spectra of the starch samples were obtained through an IR PRE-STIGE-2  in wavenumbers of 400–4000 cmC and IA refer to the cumulative diffraction intensity of the crystallized region and the amorphous region, respectively.An X-ray diffractometer  under 40 kV and 40 mA with Cu Kα radiation was used to analyze the samples’ crystalline structures. Data were obtained between 4 and 40° (2θ) at a rate of 4°/min. The RC values of the samples were determined with Equation (13):Morphology of the samples was detected by a scanning electron microscope . The samples were coated with gold and measured at an accelerating voltage of 20 kV.60S during digestive-tract digestion was determined by a dialysis method based on Mohammadian et al. [t/M∞ is the cumulative release rate of resveratrol at t time (%); k0, k1, kH, and kP are the release-rate constants; and n is a dimensionless number.The release rate of resveratrol from Res-NS and Res-Un et al.  and Chi n et al.  with somAll tests were repeated in triplicate. The experimental data were analyzed by SPSS 23.0 using analysis of variance (ANOVA) and Tukey’s multiple-range test at the 5% significance level.Changes in the CI values of the starch–resveratrol complexes with different ultrasound-amplitude treatments are presented in 60S significantly increased whereas its SP gradually decreased. This could have been caused partly by the structural change and the facial cavities after ultrasonic treatment, thereby providing channels, contributing to water penetration, and diffusing into granules. These findings support the result of Hu et al. [60S, the starches’ S and SP were reduced after being treated with resveratrol (Res-NS and Res-U60S). The decrease in solubility could have been due to the cross-linking promoted by resveratrol in starch molecules that compacted the starch–resveratrol complex’s crystal pattern [The S and SP of the starch reflect the capacity of dissolution and water absorption, respectively. The S and SP of all samples in the range of 50–90 °C are exhibited in u et al.  and Monru et al. . Ultrasou et al. . The decu et al. . Whether pattern , and the pattern . Further60S was higher than that of U60S. This effect may have been due to resveratrol acting as a mediator to form a starch–resveratrol–starch network structure by improving the OAC of starch.The oil-absorption capacity (OAC) of starch could be an index for the process of oily starch-based food products. The OAC values of different starch samples are shown in 60S were significantly reduced when in a complex with resveratrol, indicating that resveratrol could have enhanced the freeze-thaw stability of starch. With the cycles increasing, either ultrasound or resveratrol treatment could have decreased the syneresis. Okonkwo et al. [60S.The content of separated water during the freeze-thaw process indicated a trend of starch retrogradation and was evaluated by syneresis . Figure o et al.  reportedo et al. . Hence, o, Tp, and Tc) and the enthalpy change (ΔH) are shown in 60S) had significantly higher onset, peak, and conclusion gelatinization temperatures than those of NS. The enthalpy change (ΔH) of U60S was also higher than that of NS. The ratio of amylose and amylopectin affected the gelatinization of the starch. Ultrasonic treatment could have promoted amylose to seep out from the inner structure of the starch and partially gelatinize the surface of the starch under high temperatures. This may have prevented further water penetration and caused the thermal energy to increase [60S) increased compared with the samples without resveratrol. This finding suggests that resveratrol could increase the energy requirement in starch gelatinization by acting as a bridge to increase the recombination of starch molecules and crystallization order. Thus, more energy is required to reduce the dense crystalline structure of starch [The thermal characteristics of different starches were determined by DSC. The thermal parameters  were higher than those of NS. In comparison, tan δ (G″/G′) was smaller than that of NS, showing that U60S had stronger gel strength than NS. Generally speaking, when the G′ increases, the tan δ decreases, which means polymer cross-linking occurs [60S may have been due to permanent cross-linking in the sample. Monroy et al. [The dynamic rheological properties of samples are shown in g occurs . Therefoy et al.  revealedy et al. .The G′ and G″ of starch paste increased markedly after complexation with resveratrol. The resveratrol acted as a bridge between starch molecules, and it was beneficial for forming a starch or starch–resveratrol–starch network, causing the viscoelasticity of the starch paste to increase. Chi et al.  revealed60S > Res-U60S.The hydrolysis patterns and logarithm of slope plots of banana starches after different treatments are shown in ∞ of hydrolysis were calculated using a first-order model through the digestion curve  larger than that of NS, whereas SDS content was significantly lower. This agreed with the report of Han et al. [The modified starch can be classified into RDS, SDS, and RS based on different digestion levels. From n et al. . The incn et al. . When thn et al. . Moreoven et al.  reported−1, 2925 cm−1, and 1654 cm−1, corresponding to O-H, C-H, and -CH2 stretching vibrations, respectively [−1 is the fingerprint-structure region of the starch. The absorption peaks at 1047 and 1022 cm−1 are related to the crystalline and amorphous structures of the starch, respectively. The absorbance ratio of 1047/1022 cm−1 (R1047/1022) reflects the degree of short-range order on the surface of the starch granules [60S) had a higher R1047/1022 than that of NS. Compared with NS and U60S, R1047/1022 of Res-NS and Res-U60S increased after adding resveratrol. The increase in R1047/1022 indicates that ultrasound and resveratrol treatments could increase the short-range order of samples and can be explained by some of the dispersed starch chains being tightly packed in amorphous regions after ultrasonic treatment. In contrast, resveratrol was bound to the starch chains through non-covalent interactions and acted as a cross-linking agent that enhanced the molecular organization [The ATR-FTIR spectra of the samples are exhibited in ectively . There wectively  and Su eectively . The bangranules . Banana nization ,35.X-ray diffraction patterns were used to characterize the crystal structure of the starch samples. The crystalline features of the different treatments are displayed in 60S) increased compared with the samples without resveratrol . Resveratrol bound to hydrogen groups in the α-D-glucose of amylose or amylopectin chains in starch granules. It then stacked aromatic residues with the amylopyranose ring through 2–3 CH-π bonds and caused the amorphous molecules to become more ordered with an increase in RC [The RC of the sample increased from 29.06% to 30.96% after ultrasonic treatment. Compared to crystalline regions of starch, ultrasonic treatment significantly affected the amorphous regions. This agrees with a previous study . The arrse in RC ,52. ThisThe morphological changes in the modified banana-starch granules by ultrasonication and resveratrol treatment are exhibited in 60S under intestinal conditions are summarized in 60S after 150 min in the intestinal fluid were 51.48% and 40.32%, respectively. The lower release rate of resveratrol from Res-U60S could be accounted for by the more uniform structure of lowered digestibility. Thus, Res-U60S had good retention and sustained release of resveratrol [60S were found to be more consistent with the first-order model (R2 > 0.99). Additionally, the release rate was proportional to the time. This indicates that the diffusion was caused by the relaxation of the starch structure driven by distance [In vitro release behaviors of resveratrol from the starch–resveratrol complexes were evaluated using a dialysis method under conditions that simulated the digestive tract . The fitveratrol ,28. Basedistance .This work researched the effects of modification by combination of ultrasound and resveratrol treatments on the physicochemical properties and in vitro digestibility of modified banana starch. The ultrasound and resveratrol enhanced the strength of the gel and the viscoelasticity (G′ and G″), respectively. The banana starch was complexed with resveratrol through non-covalent interactions, resulting in the modified starch having a more compact structure and higher thermal stability. Additionally, after the modification, the degree of hydrolysis of the modified banana starch was reduced, whereas the contents of RDS and RS increased as the content of SDS decreased. Therefore, this new modification method could be beneficial for controlling starch structure and digestion behavior. The modified starch could be beneficial to the application of antioxidant phenolic and resistant starch.


Complete mitogenomes provide useful information for investigating the molecular evolution and phylogenetic relationships of insects. This paper reports three new aphid mitogenomes, and provides comparative genomic analyses to investigate the evolution of some unique features of aphid mitogenomes. All three mitogenomes contain the unique tandem repeat region and exhibit notably rearranged gene orders. We provide new support for the idea that tandem repeat region is an ancient feature of aphid mitogenomes, and also demonstrate that the discovered striking gene rearrangements in some aphid mitogenomes are independent clade-specific evolutionary events at certain taxonomic levels. This study improves our understanding of aphid mitogenome evolution.Ceratovacuna keduensis, Pseudoregma panicola; Lachninae: Nippolachnus piri) and compared them with all known aphid mitogenomes. The three mitogenomes are 16,059–17,033 bp in length, with a set of 37 typical mitochondrial genes, a non-coding control region and a tandem repeat region. The gene orders of them are all highly rearranged. Within the subfamily Hormaphidinae, the presence of repeat region and mitogenome rearrangement in Cerataphidini species but not in the other two tribes indicate that these may be Cerataphidini-specific features. The same gene rearrangement pattern in the two Lachninae species, N. piri (Tuberolachnini) and Stomaphis sinisalicis (Stomaphidini), supports that this feature should be at least derived from the common ancestor of two tribes. Overall, our data and analyses provide new insights into the evolutionary patterns of gene rearrangement and repeat region in aphid mitogenomes, and further corroborate the potential role of gene rearrangement in elucidating the evolutionary history of different insect lineages.The complete mitochondrial genomes and their rearrangement patterns can provide useful information for inferring evolutionary history of organisms. Aphids are one of the insect groups with some unique mitogenome features. In this study, to examine whether some features in aphid mitogenomes are independent species-specific evolutionary events or clade-specific events at certain taxonomic levels, we sequenced three new aphid mitogenomes (Hormaphidinae:  The gene arrangement within insect mitogenomes is generally conserved across different taxonomic groups and identical to that of inferred ancestral insect gene order [The genomes of mitochondria are double-strand and highly conserved circular molecules with genes required for many biological processes such as energy transduction, metabolism, and apoptosis ,2. Insecne order ,4. Howevne order ,6, Thysane order , Psocoptne order , Phthirane order ,10, and ne order . Althougne order ,13, tandne order . Gene rene order ,16, and Pseudoregma bambucicola (Hormaphidinae: Cerataphidini), Stomaphis sinisalicis (Lachninae: Stomaphidini) and some species from Fordini (Eriosomatinae) and Aphidinae [trnQ and trnM has been found in all species with sequenced mitogenomes, with the exception of the basal species Baizongia pistaciae [P. bambucicola from Cerataphidini, while two Hormaphidini species from the same subfamily show a putative ancestral insect gene order [P. bambucicola or a common evolutionary feature for all Cerataphidini species. The lack of complete mitogenomes of other Cerataphidini species has limited our understanding of the real evolutionary history of mitogenome rearrangement within this clade. Moreover, the mitochondrial gene order of a Lachninae species S. sinisalicis is also highly rearranged in comparison with that of other aphids, and exhibits a unique gene arrangement pattern [S. sinisalicis or a shared evolutionary feature for Lachninae species. Therefore, the accumulation of more evidence from broader sampling or a wider spectrum of taxonomic groups is necessary to verify these assumptions. Among species-rich hemipteran insects, mitochondrial genome rearrangements mostly occur in planthoppers , true buphidinae . In Fordistaciae ,23,24. Iistaciae ; howeverne order ,25. This pattern . HoweverCeratovacuna keduensis and Pseudoregma panicola from Cerataphidini (Hormaphidinae) and Nippolachnus piri from Tuberolachnini (Lachninae), to further explore the evolutionary context of previously revealed striking rearrangement patterns in P. bambucicola and S. sinisalicis. The general organization and the gene order of the three mitogenomes were analyzed and compared with that of other available aphid mitogenomes to investigate the evolution of tandem repeats and gene arrangement patterns across different aphid lineages. These mitogenomes will provide valuable data resources for studying the evolution of mitogenomes. Moreover, a comprehensive investigation of gene arrangement patterns in these aphid mitogenomes will facilitate better understanding of phylogenetic relationships and evolutionary history of different aphid lineages.Here, we have newly sequenced and determined mitogenomes of three aphid species, including C. keduensis, P. panicola, and N. piri were collected on bamboo, Cyrtococcum patens and Pyrus, from Fujian Province, China, in September 2017, December 2016 and May 2016, respectively. All specimens and vouchers were preserved in 95% alcohol at −80 °C at the Insect Systematic and Diversity Lab at Fujian Agricultural and Forestry University, Fuzhou, China. Genomic DNA was extracted from female adults of each species using DNeasy Blood &Tissue Kit  according to the manufacturer’s instructions, and the DNA concentration was measured using a Qubit fluorimeter .Samples of C. keduensis, P. panicola, and N. piri, respectively. The raw sequencing data were pre-processed using Trimmomatic v0.35 [C. keduensis, P. panicola, and N. piri, respectively. Mitogenomes for three aphid species were assembled with NovoPlasty v2.7.1 [cox1 sequence of each species as the seed sequence. Quantified genomic DNA was used for library construction using TrueLib DNA Library Rapid Prep Kit , and then paired-end sequencing (2 × 150 bp reads) was performed on an Illumina NovaSeq platform with an average insert size of 350 bp. A total of 10.3 Gb, 10.2 Gb and 10.4 Gb of raw data were generated for ic v0.35  to removy v2.7.1  with defhttp://tandem.bu.edu/trf/trf.html (accessed on 3 November 2021)) [The MITOS web server  was usedr 2021)) . Nucleotr 2021)) . CGView r 2021))  was usedr 2021)) . The evor 2021)) .Adelges tsugae as the outgroup. Nucleotide sequences of 13 PCGs were individually aligned under codon-based alignment mode using MAFFT v7.149 [Phylogenetic analysis was conducted using PCGs from three species in this study and other aphid species with available complete mitogenomes, using T v7.149  with defT v7.149  was thenT v7.149  integrattrnE and trnF and that inserted into the control regions across different aphid lineages, the mitogenomes of C. keduensis, P. panicola and N. piri, and known complete mitogenomes of other aphids were further detected for tandem repeat sequences with the Tandem Repeat Finder. The tandem repeats between trnE and trnF or within the control region were then mapped onto the phylogeny of aphids to examine their evolutionary pattern across different lineages.To further explore the distribution and diversity of tandem repeats between Drosophila yakuba mitogenome as the referential ancestral insect gene order [The gene orders of all known aphid mitogenomes were characterized and compared with ancestral insect gene order to investigate mitogenome rearrangement patterns in aphids under a phylogenetic framework. Specifically, PhyloSuite v1.2.1  was usedne order . NotablyC. keduensis and P. panicola have a size of 16,138 bp and 16,059 bp, respectively, which are comparable to that of another Cerataphidini species P. bambucicola . In contrast, N. piri has a larger mitogenome than C. keduensis, P. panicola and most other aphids, which is 17,033 bp in length and similar to that of S. sinisalicis  from the same subfamily Lachninae  arm. In addition, there are some tRNAs without the TΨC loop, such as trnG, trnI, trnR, and trnS2 in C. keduensis, trnW in P. panicola, and trnG and trnF in N. piri  and P. panicola (92.72%) also have higher A + T contents, which are much higher than that of N. piri (86.12%) in this study and most other aphids  and one Nipponaphidini specie , do not have this tandem repeat region in their mitogenomes. The mitogenome of N. piri also contains a tandem repeat region, which is rearranged with the trnF to a new location in the downstream of trnS2 from the ancestral position between trnE and trnF. The same pattern is found in a previously reported mitogenome of another Lachininae species , which has undergone a TDRL event among the repeat region and some adjacent genes [C. keduensis is 715 bp in length, comprising nearly three copies of 241 bp tandem repeat units. In contrast, in P. panicola, the overall length of repeat region is 528 bp, consisting of two complete tandem repeat units (254 bp) and a 20 bp incomplete repeat unit. The repeat region of N. piri (589 bp) encompasses a 300 bp complete repeat unit and a 289 bp partial repeat unit.As is the case with and trnF . While tnt genes . The reptrnE and trnF and that inserting into the control region among different aphid subfamilies. Both show a scattered distribution pattern across different aphid lineages at different taxonomic levels. Similarities between these repeat sequences were investigated to understand the evolution of tandem repeats. Notably, the tandem repeats generally found between trnE and trnF differ greatly from those inserted into control regions in size and number of tandem repeat units among different aphid lineages  show higher sequence similarity, and that of two Fordini species (N. ibofushi and S. chinensis) are identical. In addition, there are two extremely similar and discontinuous tandem repeats with both almost identical lengths and copy numbers of repeat units inserted into the control regions of four Kaburagia rhusicola subspecies and their closely related M. flavogallis. Similar CR repeat sequences have also been found in some Aphidinae species: for example, the control regions of A. pisum and B. brassicae contain exactly the same tandem repeats in their mitogenomes, and relatively high similarity is also detected among CR tandem repeat sequences of four Aphis species. The RR tandem repeats of three Cerataphidini species show high sequence similarities with each other. There is also a high-level sequence similarity between RR tandem repeats of two closely related Fordini species (N. ibofushi and S. chinensis), but both show a poor alignment with that of more distantly related species N. yanoniella from the same tribe. In addition, high sequence similarities are also detected among RR repeat sequences of five Greenideinae species from different tribes, and among 10 Aphidinae species from two tribes. While there is a low sequence similarity among species with relatively distant relationships, such as two Lachininae species  from different tribes. Thus, the distribution of both types of tandem repeats shows no clear phylogenetic patterns across or within aphid subfamilies or genus. Only some related species belonging to the same tribe show higher sequence similarity of CR tandem repeats. While for tandem repeats between trnE and trnF, it seems that most species belonging to the same subfamily have similar repeat sequences except for a few species with relatively distant relatives.lineages . There iN. piri (Tuberolachnini) mitogenome exhibits a different gene arrangement pattern from C. keduensis and P. panicola and most other known aphid mitogenomes, but shows the same dramatically rearranged gene order as S. sinisalicis, another Lachninae species belonging to tribe Stomaphidini  , there are five other types of gene arrangement in aphid mitogenomes, which are represented by 20 aphid species from three distantly related clades a. For thaphidini a,b. The and nad1 . This reType II) b.C. keduensis and P. panicola share the same mitochondrial gene order with P. bambucicola, and these three Cerataphidini species exhibit a highly rearranged mitochondrial gene order (Type III)  a,c. ThesnS1-trnR c. HowevenS1-trnR a. Thus, trnQ and trnM (Type IV) occurred in most Fordini species and concurrent trnF duplications resulted in two and three copies of trnF in N. yanoniella (Type VI) and S. chinensis (Type V), respectively  [S. sinisalicis (1489 bp) [M. persicae (2531 bp) [G. ficicola (1598 bp) [Our analyses show that the lengths of the non-coding control region (CR) and repeat region (RR) vary widely among mitogenomes of different aphid species, which in turn can drive major differences in mitogenome size. Aphids with larger mitogenomes usually contain longer CRs or RRs, such as the larger tandem RR in 2343 bp)  and S. s1489 bp) , and the2531 bp)  and G. f1598 bp) . The CR 1598 bp) . Our ana1598 bp) . S. sinisalicis and N. piri), provides further evidence for the widely accepted hypothesis that RR likely originated from the most recent common ancestor of Aphididae and has been lost many times during subsequent species diversification [The dispersed distribution pattern of RR within and among different aphid subfamilies, coupled with its presence in the basal Lachninae species  from different tribes of Lachninae, which represents a particular aphid lineage comprising various clades feeding on both conifers and broad-leaved plants. This particular rearrangement pattern further indicates that this gene arrangement is at least a common feature derived from the most common ancestor of Stomaphidini + Tuberolachnini, and even probably a common feature for all Lachninae species. Considering Lachninae includes other tribes in addition to Stomaphidini and Tuberolachnini [An extraordinary mitogenome rearrangement involving five PCGs, five tRNAs, and the RR caused by TDRL event is observed in mitogenomes of two species  and Stomaphis sinisalicis (Stomaphidini), have a same large-scale gene rearrangement pattern, which may suggest that this feature is derived from at least the common ancestor of Stomaphidini + Tuberolachnini or even the ancestor of Lachninae. Our analyses also provide further evidence for the hypothesis that the repeat region likely originated from the most recent common ancestor of aphids. Overall, our study provides new insights into the evolution of gene rearrangement and repeat region in aphid mitogenomes, and the obtained mitogenomes provide important data resources for future comparative studies.This paper reports three new complete mitogenomes of Hormaphidinae and Lachninae species. All three mitogenomes contain a tandem repeat region normally between


With the gradual expansion of China's political, economic, and military strength, the rapid rise of China has become a globally recognized fact. At present, although China's international image as the world's second largest economy, military power, and political power has been increasingly accepted by the global community, China's image construction, as an important part of national soft power, is still facing many problems. This chapter focuses on defining the basic concepts of international publicity, China's soft power, and China's image construction in the context of new media integration, analyzes the international development trend of international publicity and the important functions and limitations of foreign publicity in establishing China's image construction, and analyzes the ecological environment of media integration development. Considering that there are great unfairness in the environment and the conflict of communication values is not conducive to the establishment of China's urban image, the article focuses on how to use global publicity values to establish China's national image and puts forward corresponding countermeasures. Entering the twenty-first century, the information media with the network as the media is further expanded and innovated. Various kinds of we media and emerging media represented by Weibo, WeChat, and short videos have gradually replaced traditional media such as newspapers, magazines, and radio and become the young people's access to various media . The maiIn the past, China's image construction through online media has achieved laudable achievements and effects. Western media and the public understand China through online media. Therefore, this paper selects the research perspective of international communication ecology to take care of the construction of China's national image. This is because, firstly, international communication is the main way to shape a country's image; secondly, the systematic research method of ecology can not only give us a macroscopic and holistic research perspective but also help us to clearly understand the inner workings of the international communication system, laws, and their interaction with external systems.This paper selects the research perspective of international communication ecology to take care of the construction of China's national image . This isIn terms of political ideas, the current domestic discussions on national image construction in China are relatively macro, and few people have combined the whole media and international communication capacity of China's image construction. From the research and collation of relevant books and articles, we can see that many academic achievements have been made in the independent scientific research of “Chinese English websites,” “foreign publicity,” and “Chinese brands” in China. However, it is rare to discuss the construction of “national image” from the perspective of global communication. In the books and articles sorted out by the author, the in-depth study of the connotation of “international communication” and “national image” focuses on the study of the current situation and strategies of international communication, as well as the analysis of the current situation and strategies of the overall construction of China's urban image. The overall construction of China's urban image is placed under the condition of global publicity of online media, and there is less research on the national image construction mode and construction path under the following conditions.The concept of Convergence Media is developed on the basis of all media communication formats . It is aAs a new media product that deeply integrates the advantages of traditional media and new media, the social information dissemination environment it creates has the following characteristics . (1) It As far as the national image in the era of globalization is concerned, it is no longer just a one-way process of explaining itself to the international community from a subjective perspective. In the context of the era of media convergence, information transmission, and communication, sending and receiving have become a multidimensional process of flow. Only from “my perspective,” in today's era of information explosion with highly developed Internet media, it is impossible to effectively accomplish the strategic goal of national image construction.Specifically, the factors that constitute and affect the national image should also be comprehensively considered from three aspects: objective, subjective, and specific implementation methods. First, from an objective perspective, the influencing factors of its national image mainly come from the display of its strength, that is, the overall impression of a country's economic, military, cultural, diplomatic, and other aspects to the public at home and abroad. Second, from a subjective point of view, the manifestation of a country's national image also depends to a large extent on the cognition and interpretation of its audience, and this process often cannot be dominated by active national image construction and dissemination. Third, from the perspective of implementation, in the process of building and publicizing a country's national image, it is not only the public who have considerable ability to discriminate information and the media with established concepts, so the initiative to carry out the national image is not limited.International communication refers to the phenomenon of cross-cultural information exchange and communication between individuals and organizations of different nations and countries in the world today . It is tThe so-called national image refers to the subjective judgment and public opinion reflection of the history and reality of a specific country in the minds of the public and is an important content and concentrated expression of a country's soft power. Generally speaking, the national image has the following characteristics: first, diversity, because the national image is a complex and pluralistic complex, which includes the political, economic, cultural, social, technological, and other aspects of the country, so the national image in the minds of the public is only the right image of the country; the second is duality, because the relevant information actually obtained by the public and its observation perspective, personal experience, knowledge level, and emotion. There are differences in attitudes and other aspects, so the national image obtained may not be completely equivalent to the objective fact itself, which can be displayed as the objective reality of the country, or it can be displayed as a certain degree of illusion; the third is plasticity, the public's understanding of a country. A good national image is an extremely important strategic resource of a country and plays a vital role in promoting the realization of national interests. First, it is conducive to gaining the recognition and support of the domestic people and the international community, consolidating its legal status, inspiring people's morale, and enhancing national cohesion; second, it is conducive to influencing the behavior of stakeholders between countries, promoting international economic and trade activities, and expanding international market space; third, it is conducive to creating an international public opinion environment for the development of the country, providing the most powerful legal defense for participating in international affairs, and improving the initiative to participate in international affairs. Therefore, when we shape the image of the country, we must not only pay attention to the reality and factual basis of the country itself, that is, the display of the real situation of the country, but also cannot ignore the subjective shaping. The so-called “ecology” is the natural way that hides behind the living world of human beings and other creatures, freely and spontaneously grows and functions, and quietly dominates the fate of species. Uncontrolled destruction and various environmental problems begin the first clues .  Table As a special form of mass communication, international communication also has an ecological relationship between its communication activities and the external environment, including the limitation of media technology, the control of political economy, and the influence of language and culture . These aLooking forward to the hotspots and trends of global communication ecology, the following four points deserve continuous attention: first, the in-depth innovation and reform of media communication terminals brought about by basic media innovations such as blockchain technology and 5G should be paid attention to; second, regional and country-specific media ecology changes urgently need to be refocused from the perspective of global politics and communication ecology. There are three levels : the oriSince the 18th CPC National Congress, China is undergoing an extensive and in-depth social transformation. In this process, China's international communication can be said to be the coexistence of opportunities and challenges and the coexistence of achievements and problems.In the new era, the state has launched a new round of media integration development and reform and innovation and strengthened the attention and support for comprehensively promoting media reform. Chinese media have made important achievements in the construction of “hardware” and “software.”From the analysis of the global policy environment of international exchanges, whether the United States and some western developed countries believe in the Soviet Union and China politically, the disintegration of the Soviet Union also led to the disintegration of the former “socialist camp” and led to the formation of unipolar forces between the country and some Western European countries. The United States is the strongest economic power in the world today, and its per capita GDP is 40 times that of China. This is equivalent to a 1% increase in US GDP. Politically, the United States has always adopted an attitude of distrust towards China, which is essentially the distrust of capitalist countries towards socialist countries. In international politics, the United States' consistent lack of confidence policy towards China essentially refers to the capitalist countries' lack of confidence in the democratic system. In this regard, the term “strategic partner” has become a superficial diplomatic term.Secondly, as far as the language spread abroad is concerned, the main problem is Chinese. For foreigners who study with words as the basic unit, because Chinese is a very complex language, their acceptance of Chinese is also very low. Moreover, China has invested a lot in the introduction of Chinese. Compared with the introduction cost of tens of billions of dollars in advanced regions such as Britain, France, and the Americas, it can be considered as “insignificant.” In addition, as shown in According to the analysis of the current situation, the global communication conditions in which China is located are even worse. Therefore, the determined historical mission of the global promotion of Chinese language must be as follows: to make the world aware of China's economic and social development and world progress, understand China's history, understand the natural, economic, and development values of the Chinese nation, improve the global understanding of Chinese language, and promote the peaceful coexistence of Chinese and the world.The human world is a complex society composed of diversity, and the existence of different civilizations forms a colorful world. In international communication, news is one of the most basic information circulating in the world. Through news, we learn about changes in the environment and the world around us, forming our impressions and attitudes towards things. News in international communication is not purely objective information; it is the reporting of newly occurring facts. Since it is a report, it is a human activity, which inevitably involves human consciousness for processing and human cognition and judgment.Second, there are great inequalities in the context of international communication. The main tool for shaping a country's image through international communication is the media. However, the current distribution of mass communication resources in the entire international community is extremely unequal.As the main force of China's foreign reporting, Xinhua News Agency can only broadcast more than 800,000 words of news in 7 languages every day. There are only 13,091 news users, of which only 4,144 are overseas users; while Reuters uses 24 languages every day for 151 countries. Third, the overall image of developing countries is distorted. Although the use of foreign media to shape a country's national image is now a common method, in essence, the fundamental purpose of international communication is still to serve the country's politics and ultimately safeguard the country's political interests. Correct understanding will in turn lead to a stereotyped image of a big country, that is, people's stereotype of a big country, because Western powers always “shape” news in China based on their own interests, and the content of the reports is all news that is beneficial to their national political interests. This monopolistic coercive method makes it extremely difficult for developing countries to try to shape their country's image through media communication.The rapid development of China in the mid-1990s has attracted the attention of some Asian countries, especially the United States. Since 1996, China's diplomatic strategy has been adjusted to focus on domestic development in order to improve overall national strength and maintain appropriate international conditions and minimize the possibility of the United States and other countries using their advantages to contain China's development. This strategy helps China unite other great powers as partners, while also curbing the formation of potentially hostile alliances to a certain extent.While continuing economic development, we must spare no effort to continue promoting the process of political civilization and change the social phenomenon with many social and legal problems and low government participation; earnestly respect human rights and strengthen the concept of human rights; adhere to the sustainable scientific outlook on development and enhance environmental protection awareness and intensify efforts in environmental protection; take the scientific outlook on development as the guiding ideology, take economic development as the foundation, and promote the all-round social progress and the all-round development of people; and actively solve the outstanding problems of China at the current stage that are concerned by the international community, especially the hot issues. This will give the international community an opportunity to fully understand China.Can actively strengthen people-to-people exchanges. In the process of shaping its national image, China needs to actively cultivate the participation of diverse actors, strengthen nongovernmental exchanges and cooperation, deepen nongovernmental understanding, and consolidate the social foundation of friendship and mutual trust. It is necessary to intensify economic cooperation. Promote exchanges between youth, women, media, and other NGOs with foreign countries and deepen nongovernmental understanding.In the era of peace and development, along with the pace of reform and opening up, China has gained a more comprehensive and profound understanding of the international community and international system and has begun to handle international affairs and interstate relations from the perspective of national interests. Actively and fully integrate into the international community with respect, understanding, support, cooperation, cooperation, and utilization, and highlight the importance and urgency of seeking survival and development. Therefore, we must actively carry out public diplomacy. Public diplomacy has become an important means for countries to shape and disseminate their national image and thus effectively exert “soft power.” Diplomacy has an impact on public opinion, and public opinion also has an adverse effect on government decision-making. Public diplomacy has achieved certain results.The concept of international communication currently existing in China is relatively backward, and this imperfect international communication system has led to the formation of a wrong national image in the eyes of other peoples. From a global perspective, environmental problems have gradually emerged in the process of human understanding and transformation of nature.“The solution of ecological environmental problems not only depends on the progress of technology but also on the improvement of ecological civilization awareness.” Human production and life cannot be far away from nature, nor can it not be affected by nature. Man and nature are closely linked and inseparable. Regarding the relationship between man and nature, Xi Jinping emphasized that man and nature are closely related, and between man and nature, nature is the first, and the relationship between man and nature belongs to the relationship between the large system of nature and the people it contains; between nature and nature, human beings depend on nature and need to use and transform nature. However, no matter how high human production progresses, human beings cannot surpass nature. There is no human being above nature. Human beings are always a part of nature.Secondly, in overseas exchanges, we have paid attention to the great power of humanistic diplomacy, nongovernmental diplomacy and film and television diplomacy, as well as the need to highlight the common will of mankind and reduce unique political propaganda and large and empty grand narratives, and stereotyped positive reports. Turn to more active and specific people and listen to their needs in order to enhance the permeability and effectiveness of communication. We should be soberly aware that the strength and status of domestic social media in the global development cannot be compared with Twitter and Facebook. At the same time, the influence of CCTV's English channel overseas is also very limited, and the audience's language needs are greater than information needs.The use of media events to construct a national image reflects the comprehensive planning and agenda setting functions of the media. Mannheim pointed out that if a country is to seek admiration and a positive image on the world stage, it must find ways to host global media events. As long as this event can firmly attract the world's attention, it will help improve the country's image. In the international communication system, more and more countries have realized the importance of media events in building a national image. They usually choose news that foreign governments and international audiences are interested in to report and integrate their subjective consciousness and political stance into the news information and adopt a way that is easily accepted by the international community to spread, so as to shape its ideal national image. The following aspects should also be considered in the communication. First, the strategies, methods, and methods of communication should be continuously improved to realize localized communication, precise communication, global communication, and story-based communication, interesting in human. Secondly, it is necessary to strengthen the innovative use and full utilization of new technologies and new platforms and plan news reports according to the different characteristics of different platforms.Today, with the integration of media information, the deterioration of the ecological environment, and the increasing globalization of international communication, it has become an important issue that we must face up to by developing international communication to create a good national image. This paper analyzes the current situation and existing problems of China's international communication and national image under the ecological environment and puts forward corresponding suggestions accordingly. It aims to achieve the purpose of shaping China's national image through the continuous improvement of international communication in terms of awareness, technology, means, and skills. Establishing an ideal national image is not something that can be achieved overnight. It must be through our continuous exploration and efforts, a lot of hard work and material investment, and the development of a good ecological environment. Only by strengthening this belief can we compete in the increasingly fierce international communication. Only by gaining a place in China can the national image of China be continuously improved in accordance with our expectations. The continuous evolution and integration of media with the support of technology has created extremely favorable conditions for the transnational dissemination of information. On the one hand, domestic public opinion needs to use information transmission channels to say good things; however, they must spare no effort to establish a local global flagship media, as the most important source of information in the world today, establish a national brand, interact with mobile networks, organically integrate into social media, and form a comprehensive three-dimensional all media publicity matrix, and lay a solid foundation for the realization and dissemination of national image. We should be more aware that it is a difficult and long project to establish an ideal national image of China from the perspective of global communication, so we need to have more perseverance, patience, and courage to achieve this goal.


Objective: One-leg standing has been used exclusively for static balance testing and training purposes. We investigated the acute effects of one-leg standing with open or closed eyes on arterial stiffness in older women and explored the role of standing dose in arterial stiffness regulation.Methods: Eighteen older women (60 ± 2 years) underwent non-intervention control (CON), one-leg standing with open eyes for 2 × 3 min (SO2), and one-leg standing with closed eyes for 1 × 3 min (SC1), 2 × 3 min (SC2), and 3 × 3 min trials (SC3) in a randomized self-controlled crossover fashion. Arterial stiffness in the cardio-ankle vascular index (CAVI) was measured at baseline (BL), immediately (0 min), and 10 and 20 min after standing. CAVI changes from BL in the same trial (⊿CAVI) were used for analysis.Results: ⊿CAVI of the non-standing and standing side did not change with time in CON and SO2 trials. In SC1, SC2, and SC3 trials, ⊿CAVI of the standing side decreased significantly at 0 min compared to their corresponding BL (p < 0.01) and reverted gradually to the BL level afterward, with ⊿CAVI of the non-standing side undergoing no changes. At the time point of 0 min, only in the SC2 trial, ⊿CAVI of the standing side was significantly lower than that of CON (p < 0.01).Conclusion: One-leg standing with closed eyes, but not with open eyes, resulted in transient arterial stiffness improvement in older women. The improvement was restricted to standing leg, and the moderate standing dose had maximal benefit on arterial stiffness. Arterial stiffening is prominent in older people and could increase the risk of cardiovascular diseases. Strategies that combat the age- and sedentary-associated increase in arterial stiffness are of great importance. Compared to aerobic and resistance exercises, standing is more accessible in practice. However, current evidence does not support the efficacy of two-leg standing on arterial stiffness in humans .As an ancient body-mind practice, yoga could reduce arterial stiffness in older people . Since yOLS has long been exclusively adopted in static balance training and testing . Visual Therefore, this study aimed to examine the acute effects of OLS with eyes open or closed on arterial stiffness and investigated whether the dose of OLS influences the extent of arterial stiffness improvement in older adults.Eighteen healthy older women (age 60 ± 2 years) participated in the study , with 11All participants underwent five trials including non-standing control (CON), one-leg standing with eyes open for 2 × 3 min (SO2), and one-leg standing with eyes closed for 1 × 3 min (SC1), 2 × 3 min (SC2), and 3 × 3 min trials (SC3) in a randomized self-controlled crossover fashion . In the All participants abstained from vigorous activity and alcohol or caffeine intake over the day before each trial. Participants entered their own trials once a week for five consecutive weeks on the same timing of the day, fasting at least for 3 h, and rested quietly for at least 15 min before baseline measurement. All the trials were conducted with room temperature ranging from 22 to 25°C in the Cardiovascular Health Laboratory of the Capital University of Physical Education and Sports.The participant was asked to stand on their left leg, with eyes either open or closed for single or multiple 3-min bouts whilst flexing the contralateral knee. The left leg was chosen for all the participants in all the standing trials, for the dominant and the non-dominant leg can be used interchangeably during static one-leg balance testing . All theUsing a VaSera 1500 vascular screening system , arterial stiffness was evaluated in the cardio-ankle vascular index (CAVI), an index of systemic arterial stiffness that reflects the condition of the aorta, femoral artery, and tibial artery. With the subjects in the supine position, electrocardiogram electrodes were placed on wrists, a microphone for monitoring heart sounds (phonocardiogram) was placed on the sternum, and four cuffs were wrapped around the upper arms and ankles. When the electrocardiogram was stable and the first and second heart sounds were detected in the phonocardiogram, the START button was pressed, and the values of right and left CAVI were obtained using the system completely independent of human operation.Measurements of blood pressure and heart rate were made simultaneously by the system.post hoc test was performed to probe the time point at which the difference between trials existed and to identify the significant changes with time within the trial. The statistical significance level was set at p < 0.05.Statistical processing was performed using GraphPad Prism Software 8.0. All data are expressed as means ± SEM. CAVI changes from BL in the same trial (⊿CAVI) were used for analysis. The responses of ⊿CAVI, HR, and BP to exercise were analyzed by two-way (treatment × time) ANOVA of repeated measures. A **p < 0.01 vs. BL, ****p < 0.0001 vs. BL, 10, and 20 min, **p < 0.01 vs. BL, 10, and 20 min, $p < 0.01 vs. CON trial at the same time point, As can be seen in Specifically, ⊿CAVI of the standing side remained unchanged with time in both CON and SO2 trials . In the As seen in As indicated in Our findings are that OLS with closed eyes, in contrast to open eyes, acutely improved arterial stiffness of the standing side in older women. However, this transient effect was attenuated when the dose of OLS was either increased or decreased.Evidence demonstrates that sedentary time is positively associated with arterial stiffness , and sedCompared to bipedal standing, OLS is more challenging due to the narrower support base  and the Vision is one of the elements of the system responsible for maintaining static balance and provides important sensory information required by balancing. Any visual impairments or conditions hampering the reception of visual stimuli may affect the static balance. Mechanical instability needs to be counterbalanced by the precise activation of multiple muscles , and thuOur results showed that after OLS with closed eyes, no matter what the bout number is, the arterial stiffness of the standing side in the older women improved significantly, though transiently. In our study, the legs experienced the same hydrostatic pressure due to gravity in both closed- and open-eye trials, and thus, one-leg standing-induced shear stress did not significantly differ between both trials. So, it seems unlikely that hydrostatic pressure led to the impact of one-leg standing with closed eyes on arterial stiffness. Considering that intensity is an important determinant of the physiological responses to exercise training , we propIn this study, the mild but still significant improvement of arterial stiffness in terms of CAVI induced by closed-eye OLS is comparable to that observed in acute aerobic exercise  and longHowever, In this study, brachial systolic blood pressure tends to increase immediately after standing overall and reached significance after three bouts of standing with closed eyes. This supports the notion that heart rate and blood pressure increase in order to acutely meet the metabolic demands of the working skeletal muscle during exercise  and indiGuidelines recommended that older people participate in aerobic and muscle-strengthening activities above minimum recommended amounts to gain additional health benefits and higher levels of physical fitness . SimilarThe results showed that, though all OLS protocols with closed eyes have significant impact on arterial stiffness in older women, the optimal protocol is two bouts of 5-min OLS, and the attenuation of the impact was observed when the OLS bout number was either increased to three or decreased to one. Specifically, an increase in OLS dose within a very narrow range (from one to two bouts) produced augmented response. This reminds us that caution should be taken on the dose of OLS in practice to ensure that OLS can have maximal health benefit. Furthermore, whether a fourth or more bouts will deteriorate, and even abolish, the arterial stiffness improvement induced by OLS warrants further investigation.The phenomenon that a third bout of OLS attenuates the impact of previous two bouts is very similar to that of ischemic conditioning. In dose–response studies, researchers found that an increased number of ischemic cycles could attenuate, or even abolish, the beneficial effects that a certain number of cycles produced . This waPrevious studies demonstrated that only arterial stiffness in the exercised leg decreased after acute aerobic exercise , resistaFirst, we enrolled older women with both normal and above-normal blood pressure; however, we used self-control design in this study, and the results indicated that the results might apply to people with both normal and above-normal blood pressure. Second, we, somewhat arbitrarily, fixed the interval between standing bouts at 1 min in this study. Since the interval between cycling bouts may influence arterial stiffness improvement , whetherThough OLS with open eyes was not a sufficient stimulus to elicit an arterial stiffness decrease in older women, OLS with closed eyes could transiently improve arterial stiffness in the standing side but not the non-standing side. Moderate standing dose was necessary in order to benefit arterial stiffness the most. Our study provided an easily accessible protocol for older women to condition arterial stiffness at any time when they wanted to exercise, and this will contribute to the improvement of cardiovascular health and the prevention of cardiovascular diseases of older women.


In this study, the effects of the amylose/amylopectin content on starch gelation and the physical characteristics of hydrogels produced by HPP were studied by optical and rheological measurements in steady-state conditions. Additionally, the effects of the storage temperature (4 °C and 20 °C) and type of packaging  on the physical stability of the hydrogels were evaluated for 30 days of storage by evaluating the shrinkage of the granules, as well as the weight loss, water activity, organoleptic, and rheological properties. The experimental findings suggested that amylose plays an antagonistic role in determining the capacity of the starch granules to absorb water under pressure and to create stable and structured gels and on the physical stability of hydrogels due to its influence over the starch retrogradation extent during storage. Twenty per cent amylose was the minimum concentration to form stable corn starch HPP hydrogels with good physical and rheological properties. Moreover, a storage temperature of 20 °C and the use of polymeric bags were evaluated as the most suitable storage conditions and packaging materials enabling the long storage of corn starch hydrogels. Hydrogels are physical or chemical cross-linked macromolecules forming a stable three-dimensional network capable of retaining or absorbing a significant amount of water . Their cInnovations in the field have been recently proposed and are receiving significant attention from the scientific community, mainly consisting of the utilization of renewable and biodegradable sources, such as cellulose, lignin, pectin, and starch, as natural polymers to produce hydrogels . Starch,Another recently proposed innovation consisted of the utilization of high-pressure processing (HPP) technology to achieve a sol–gel transition and obtain starch-based hydrogels. HPP is a well-known non-thermal technology consisting of subjecting a product, packaged in flexible containers, to the action of the pressure which is applied through an intermediate pressurizing medium in the range from 100 to 1000 MPa for a short time (from a few seconds to minutes) at controlled temperature conditions. Under HPP, starch-in-water suspensions experience structural and morphological changes due to the hydration and/or to the melting of crystalline structures due to compression forces and, once the threshold values of the pressure and processing time are overcome, the sol–gel transition of the system is likely to occur. On the one hand, HPP technology enabled overcoming the main limitations of the conventional gelation methods, especially a long processing time and energy consumption, and, on the other hand, obtaining hydrogels displaying good mechanical properties, stability, and a promising functionality ,24,25. SThe ability and effectiveness of HPP to form hydrogels have been proven by utilizing different starches, namely potato, tapioca, rice, corn, and wheat starches. Regarding the amylose/amylopectin ratio characterizing starch composition, it has been shown that under HPP, the amylose content could play an important role in determining the changes in the structural characteristics and physical properties of starch granules and starch suspensions ,33,34,35Several authors have investigated the effect of HPP on the physical properties of starch granules and starch suspensions with a different amylose content ,39,40,41The gel formation under HPP can be described as the hydration process, in excess of water, of the amorphous and crystalline regions of starch under the action of compression forces. The gelation occurrence in extent as well as the structuring level of the hydrogels formed depends on several factors, including the pressure, time, and amylose/amylopectin content, among others. The occurrence of gelatinization in starch suspensions can be assessed if the characteristic “Maltese cross” is not visible when the starch granules are observed under polarized light .Therefore, based on the obtained results, further analyses were carried out on stable HPP hydrogels, namely those produced at 600 MPa for 5 min with normal and waxy corn starch, as described in the following.Starch-based hydrogels produced by HPP are structures formed by physical non-covalent interactions of a reversible nature. Their non-permanent behavior should be examined thoroughly to understand to which extent the mechanical properties of starch-based hydrogels change over time due to water evaporation . In thisAs can be observed in Additionally, the differences between the physical appearance of the hydrogels investigated in this work were observed during the storage period. After 30 days of storage, waxy corn starch hydrogels stored at 4 °C retained their higher brightness regardless of the type of packaging used. Normal corn starch hydrogels became drier after one month of storage. It could be hypothesized that in waxy corn starch hydrogels, water migration from the inner part of the structure to the surface causes the collapse of the structure, and then small hydrogel lumps (agglomerates) form which are mainly stabilized by non-covalent interactions such as hydrogen bonds. Xie et al.  reportedTo better understand the role of the amylose/amylopectin content on water evaporation dynamics from starch-based HPP hydrogels, the shrinkage index and weight loss of all samples were evaluated. To this purpose, the initial granule size values and weight of all samples immediately after HPP treatment (day 0) were compared with those hydrogels at the end of the storage period (day 30) at the two different temperatures set, and the results are reported in ® sealing, promotes the migration of water from the structure to the environment, meaning this mass transfer phenomenon was facilitated at higher storage temperatures (20 °C). On the contrary, hydrogels packaged in plastic bags are characterized by a lower shrinkage of the granules and a reduced weight loss (<20%). Waxy corn starch hydrogels stored at 20 °C were those showing the lowest values of the shrinkage index compared to normal corn starch hydrogels. However, a lower weight loss was detected in the latter’s structure. This interesting finding reinforces the hypothesis that amylose molecules may hinder the capacity of starch granules to absorb water during the formation of a gel under a high pressure, and even though a complete gelatinization was observed in normal corn starch hydrogels, hydrogels formed with starches composed of almost 100% amylopectin molecules entrapped more water and, therefore, more water became available to be primary released; thus, less shrinkage was likely to occur. Moreover, the shrinkage observed in both samples could be attributed to starch retrogradation phenomena. It is well known that starch gels undergo a structural reorganization of the starch chains during storage, mainly generating water loss and shrinkage, as a consequence of the crystallization of amylose and amylopectin molecules [From olecules . Many auolecules ,47,48,49olecules . These aIn addition, waxy and normal corn starch hydrogels stored at 20 °C in plastic bags showed a lower shrinkage than those stored at 4 °C. This finding could be attributed to the higher retrogradation extent displayed by starch gels stored at 4 °C mainly due to the faster crystallization of the starch macromolecules, as reported elsewhere ,51. Recew values of hydrogel samples were initially in the range of 0.97–0.98, regardless of the amylose/amylopectin content. Moreover, a slight decrease in the water activity was detected in all samples, except in those stored at 20 °C in a Petri dish where a drastic reduction in the Aw values up to 0.57–0.66 was detected. Instead, from weight loss determinations, significant differences were detected between hydrogel samples stored in plastic bags and Petri dishes. However, through a measurement of the water activity, which is a useful tool to understand water dynamics in the starch hydrogel structures, only free water on the surface of the hydrogel samples is evaluated, as reported by Larrea-Wachtendorff et al. [w values changed only marginally during a short storage period.f et al. . The autRheological measurements were carried out to assess the mechanical properties of corn starch-based HPP hydrogels. In particular, the effects of the amylose/amylopectin content on the gelatinization and flow behavior of the samples were evaluated by flow measurements in steady-state conditions. Moreover, the viscoelastic properties of the hydrogels at different storage conditions were determined through frequency sweep tests within the linear viscoelastic region of the materials .Moreover, at 500 MPa, weak hydrogels were obtained with rheological properties far from those desired, due to the partial gelatinization extent. This confirms the results reported in In this work, an attempt to understand the influence of the amylose/amylopectin content over the structuring level and stability of starch-based HPP hydrogels formed was also made, carrying out frequency sweep tests. They provide information on the structuring level of gels by testing the physical response of materials under controlled deformation forces. The viscoelastic properties  of waxy and normal corn starch HPP hydrogels obtained at 600 MPa for 5 min were reported in It can be observed that, initially, both starch-based hydrogels exhibited mechanical profiles characteristic of physical gels, where the elastic response (G’) of the samples prevailed on the viscous response independently of the frequency, indicating that a continuous gel network was formed between starch and water molecules . MoreoveHowever, the mechanical profile of both hydrogel samples was strongly influenced by the storage time and the two temperatures investigated. After 30 days of storage, the gel network of both hydrogels was weakening, mostly related to a higher dependence of G’ and G’’ moduli from the frequency in the range investigated, and the difference between the elastic response and viscous response curves was decreasing. Higher G’ values were observed in all samples after 30 days of storage due to water evaporation and starch retrogradation. Indeed, in agreement with the results of the determination of the organoleptic properties, this trend was more marked in normal corn starch hydrogels and for samples stored at 4 °C. The G’’ values exceeded the G’ values in normal starch hydrogels stored at 4 °C; that is, a reduction in their viscoelasticity was observed. This clearly demonstrated that these samples lost their gel-like structure during storage at a low temperature. Therefore, it can be concluded that at 4 °C, starch retrogradation was likely to occur. Indeed, BeMiller  demonstrThe experimental results obtained in this work demonstrated that the amylose content played an antagonistic role in the gelatinization by HPP treatments of corn starch water suspensions and strongly affected the physical characteristics and stability of the hydrogels obtained. At high concentrations, the amylose content reduced the swelling of the starch granules during HPP processing and lowered their capacity to retain water during storage time due to starch retrogradation. The physical and rheological changes in the hydrogels during storage were mainly attributed to the ability of the type of packaging and storage temperature to control the water evaporation and starch retrogradation. Plastic bags and a storage temperature of 20 °C were the most suitable storage conditions to preserve the physical and organoleptic characteristics of the gel-like structure of corn starch-based hydrogels during storage time (30 days). Moreover, stable corn starch HPP hydrogels with good physical and rheological properties formed when the amylose content of the starch was as high as 20%.The results of this research represent a contribution to the advancement of knowledge on the role played by the amylose/amylopectin content in determining the structural and physical properties of starch-based hydrogels produced by HPP as a physical method for a sol–gel transition as an alternative to traditional and well-assessed gelatinization physical process. Nevertheless, further experiments should be performed to understand the behavior of starch-based HPP hydrogels in long-term storage in different conditions and to individuate natural compounds that could be added to the starch solution undergoing HPP treatments to retard or avoid starch retrogradation. The results of these experiments will be of utmost importance to individuate the optimal storage conditions for starch-based HPP hydrogels as well as their formulation to increase their stability and performances given the forecasted applicability of these novel structures in various product sectorsWaxy , normal , and high-amylose  corn starch powders were purchased from Sigma Aldrich . The Amylose content of the starch samples was confirmed by an enzymatic rapid assay kit .w/w) were formed under gentle mixing. In order to ensure sample homogeneity and avoid particles settling, the starch suspensions were prepared immediately before the HPP treatments.The preparation of the samples was carried out according to the method reported by Larrea-Wachtendorff et al. . BrieflyThe starch-water suspensions (10 g) were vacuum-packed in flexible bags .The high-pressure treatments were performed using an HHP system U22 lab-scale unit ; the unit has a maximum processing volume of 50 mL and can be operated at a wide range of pressure and temperature . The pressurizing medium is Plexol (Bis (2-Ethylhexyl) sebacate from Sigma-Aldrich, Italy) and the estimated temperature increase due to a pressure build-up is 2–3 °C/100 MPa.After being sealed in the packages, the samples were immediately treated at pressures levels of 500, 600, and 700 MPa for 5 and 15 min at 25 °C. In ® and stored at the above-mentioned temperature conditions. Samples at time zero (immediately after HPP processing) and the end of the storage period of 30 days were analyzed. Unless otherwise stated, all measurements were performed in triplicate.To evaluate the stability of HPP hydrogel during a short storage time and the performance of different packaging methods to preserve their physical and organoleptic properties, the samples were stored immediately after HPP treatment for 30 days at different conditions, chilling and at room temperature, 4 °C and 20 °C, respectively, and two types of packaging, namely polymeric multilayers bags and sealed Petri dishes. In the first case, the hydrogel samples were kept in the same flexible bags used during the HPP processing of the starch solutions and they were stored at 4 °C and 20 °C. To emulate the packaging conditions of regular creams or gels, the plastic bags containing the HPP hydrogel formed were opened and the samples were aseptically poured into Petri dishes, sealed with ParafilmThe starch granules’ optical size was determined using an optical inverted light microscope  coupled to a Camera Control Unit  for image acquisition and size analysis, as described elsewhere .In order to compare the water evaporation on starch-based hydrogels during storage and the hydration of the starch granules due to HPP processing, a shrinkage index was defined, based on the change in the granules’ size during gelation and at the end of the storage period. The values of the shrinkage index were calculated according to the relationship reported in the following Equation (1):D0, dD0, and dD30 are the average granule diameter of the untreated samples (corn starch in the water suspension), immediately after the HPP treatments, and after 30 days of storage, respectively.The weight loss of samples was determined as the difference between the weight of samples at the beginning and the end of storage time. For both types of packaging, the determination was made by carefully opening them, draining any excess of water, and weighing it. The weight loss was calculated according to Equation (2):The organoleptic properties of samples throughout the storage time were analyzed by a visual observation, making water evaporation and starch retrogradation the two phenomena that can affect the appearance, homogeneity, integrity, and color of starch-based HPP hydrogels . These pw) was determined using an AW-Sprint Novasina water activity measurement instrument . A total of 1 g of the hydrogel was poured into the center of the sample container and at least six measurements per each sample were performed to reach a hydrodynamic equilibrium inside the humidity-controlled chamber. Prior to the experiments, the water activity equipment was calibrated with standard salts at 25 °C.The water activity  thermally controlled by a Peltier plate and a circulating water bath . A plate-cone geometry configuration was used .For the analysis, 1.0 g of the sample was loaded in the center of the rheometer plate and kept at a set temperature of 25 °C for 2 min to allow for a stress relaxation and temperature equilibration, as reported by Larrea et al. .p-value was <0.05). All analyses were performed using Statgraphics Centurion XVI Statistical Software .The results were analyzed by statistical descriptive analysis (mean ± SD), a one-way ANOVA, and a post hoc comparison using Fisher’s least significant difference (LSD) test to determine significant differences amongst the experiments (


However, mode matching is the basis for high-precision detection, which can improve the sensitivity, resolution, and signal-to-noise ratio of the gyroscopes. An initial frequency split is inevitably generated during the manufacturing process. There are two methods to eliminate the frequency split and to achieve mode matching for the gyroscopes, which are electrostatic tuning and mechanical trimming, respectively. In this paper, we report a novel ring MEMS resonator and a novel method of mechanical frequency tuning. The most prominent characteristic of the resonator is that 16 raised mass blocks are increased in the circumferential positions of the ring uniformly. This structural design can achieve mass-stiffness decoupling, which means that punching holes on the mass blocks only affects the mass distribution but the stiffness is almost unchanged for the resonator. We verify the mass-stiffness decoupling by way of comparing the simulation with the conventional resonator. In addition, we put up an online tuning platform based on a femtosecond laser and reduce a resonator’s frequency split from 23.3 Hz to 0.4 Hz, which reveals that the frequency split is linearly related to the removed mass. These findings will have a referential significance for other transducers.MEMS gyroscopes play an important role in inertial navigation measurements, which mainly works in  MEMS gyroscopes show great superiority over conventional mechanical gyroscopes in size, power consumption, and cost. Ring MEMS gyroscopes have excellent performance advantages from their symmetrical structure and work in the case of mode-matching . Mode-maThere are two methods to realize mode matching: electrostatic tuning and mechanical trimming. In electrostatic tuning, the DC voltage is usually applied to the electrodes, which decreases the frequency of the corresponding mode of the gyroscope due to the effect of electrostatic negative stiffness; thus, the mode matching is realized. However, it does not change the structure of the resonator in essence and is very sensitive to the environmental temperature. By contrast, mechanical trimming can decrease various errors by changing the mass or stiffness distribution of the resonator. Thus it has been widely applied to high-performance gyroscopes such as micro-hemispherical or cylindrical gyroscopes in recent years.In previous studies, the mechanical trimming mainly had two methods. However, no matter whether mass is added to the structure or reduced, there are many uncertainties. For example, change of the structure will affect the mass and stiffness at the same time, making it difficult to control the frequency split. In addition, the laser ablation cannot guarantee the shape of punching holes ,4, and iTo improve the performance of the Disk Resonant Gyro, it is verified that hanging mass blocks on the ring can maintain the stiffness of the resonator . In thisThe traditional ring MEMS resonant structure is composed of a support beam and a resonant ring. Any change of mass at any location on the ring will affect the mass and stiffness distribution of the structure. The overall frame of the new ring MEMS resonant structure is a four-sided anchor a, where To achieve the effect of a ring resonator with errors, suppose that According to the above model, we can deduce that the position of the high-frequency rigid axis is satisfied with:The two frequencies of the ring resonator’s operating modes are:Furthermore, the value of frequency split can be deduced as follows:From the mathematical form of Then, we need to compute the resonator’s effective mass and effective stiffness to know whether it has the character of mass-stiffness decoupling. On the one hand, we increase the radius of the mass blocks to observe how the resonator’s effective mass and effective stiffness change  on one mass block will result in uneven mass distribution (as shown in According to the derivation of the tuning theory above: if removing the same mass at an interval of 90°, the tuning effects are equal to each other; but at an interval of 45°, the tuning effect will be canceled out. We assume that punching holes whose diameters are 100 μm and depths are 200 μm on the mass blocks of the resonator with the errors shown in From Once more, different from the punching set out in From Afterwards, we may simulate punching holes of diameter D = 150 μm, depth d = 300 μm sequentially on the resonator’s mass blocks with the errors shown in From the above In order to study the relationship between frequency split and the mass removed, now, we simulate punching holes on the ring and mass block with various diameters and depths, and then observe and record the frequency split during the punching. We take the diameters from 50 μm to 120 μm by steps of 10 μm and the depths from 50 μm to 400 μm by steps of 50 μm. We only consider punching holes on the stationary position so that we do not change the position of the rigid axis during the punching. The simulation results of punching holes on the ring and mass blocks are shown in As shown in Finally, we build an online tuning platform based on femtosecond laser (as shown in The whole experimental process is: use lock-in amplifier to sweep the gyroscope’s modal frequencies, according to the size of the frequency split then operate the femtosecond laser to punch holes on the mass blocks. After the end of the punching, sweep the frequency again to observe how the frequency split changed. We determine the next punching position and hole size by frequency split and relative amplitude of two peaks of the curve. Punch holes without a break until the frequency split meets the requirement.The gyro is separated from the test circuit board to avoid the influence of temperature, which will result in drifting in the angular frequency and lead to noise. As the laser parameters will have an impact on punching holes, such as diameter, depth and so on, we try punching holes on the dilapidated resonator for exploring which parameter is the best before the tuning experiment. The spot diameter of the laser is about 7–10 μm; we punch two holes of diameters 60 μm and 100 μm on the mass blocks, but we can see the hole’s diameters are about 70 μm and 110 μm under the electron microscope as shown in After all the simulations above, it is so important to verify if these simulation or theories are consistent with the experiment. Firstly, we punch holes of diameter 100 μm and depth 150 μm on the mass blocks of a resonator with an initial frequency split which is 15.7 Hz under vacuum. The punching sequence of the mass blocks are numbers 13, 15, 11 and 9 which are at 90° intervals. However, in the actual punching, the holes’ centers do not completely coincide with the mass blocks. The results are shown in From the results above, we can see the modal frequencies are all rising after punching, which is consistent with the simulation. Likewise, punching positions at 45° intervals cancels out the tuning effect mutually. Then, we continue punching holes on the mass blocks numbered 2, 6, 8 and 12 in order, whose diameters are 60 μm and depths are 150 μm. The results are shown in n = 2 mode of ring resonators.As we can see in Next, we begin to punch holes on another resonator under vacuum to achieve mode matching, of which the frequency sweep is shown as As shown in On the basis of the first set of experiments, the second group of experiments goes on punching holes on the mass blocks numbered 12, 8, 16 and 4 sequentially. These holes’ diameters and depths are 60 μm and 500 μm respectively. As shown in On the basis of the second set of experiments, the third group of experiments continues to punch holes on the mass blocks numbered 2, 6, 10 and 14 in turn. From On the basis of the third set of experiments, finally the fourth group of experiments is designed, in which we punch holes on the mass blocks numbered 15, 11 and 7 in order, of which the diameters are 100 μm and the depths are from 200 μm to 400 μm by the step of 100 μm. At the end of the final punching, the resonator’s modal frequencies are 24,662.3 Hz and 24,662.7 Hz. It is worth mentioning that the final frequency split is 0.4 Hz, as shown in The tuning parameters of the four sets of experiments are listed in We have come up with a new ring resonator which was different from the conventional resonator and could achieve the decoupling between mass and stiffness by punching holes on the mass blocks. Based on this structure, we put forward a novel method of permanent frequency split reduction by laser ablation. It not only increases the convenience of the frequency tuning but also lowers the damage to the structure with the laser ablation, which can reduce the quality factor of the resonator. Moreover, our research will have a referential significance to other transducers.