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A new mealybug species, Ceroputo liquidambaris Zhang & Watson sp. n. (Hemiptera: Coccomorpha: Pseudococcidae), collected on leaves and branches of Liquidambar formosana (Altingiaceae), is described and illustrated from Jiangxi, China. The new species differs from all other known species of Ceroputo in having dorsal multilocular disc pores. Notes on some aspects of Ceroputo pilosellae Šulc collected in China and a key to the adult females of Ceroputo species are provided.

A new mealybug species, Dysmicoccus lushanensis Zhang, Wang & Watson sp. n. (Hemiptera: Coccomorpha: Pseudococcidae), collected on the branches of Rhododendron simsii Planch. (Ericaceae) in Jiangxi Province, China, is described and illustrated. It is similar to another species recorded feeding on Rhododendron, D. wistariae (Green 1923), in having small conical dorsal setae and most cerarii containing more than 2 conical setae, but differs from it in having each anal lobe cerarius(C18) with more than two conical setae, and translucent pores present on the hind femur and tibia. The new species also resembles D. finitimus (Williams 1994), which is only known to feed on palms (Arecaceae), in possessing anal lobe cerarius(C18) each with more than 2 conical cerarian setae, but differs in having minute, conical dorsal setae and in lacking translucent pores on the hind coxa. In addition, D. debregeasiae (Green 1922) is recorded from China for the first time. A key to the Chinese species of Dysmicoccus is provided.

MgO nanoparticles (NPs) are widely used in bactericides, fuel cells and electronic materials and are frequently detected in aquatic environments.

Background: The incidence, risk factors, and pathogenesis of early neurological deterioration (END) in posterior circulation stroke are still unclear. In this study, we aimed to determine the risk factors and prognosis of END in patients with acute posterior circulation cerebral infarction. Methods: Acute posterior circulation ischemic stroke patients who had completed neuroimaging within 72 hours of onset were selected from a prospective registry study. Demographic characteristics, physiological data, medical history, laboratory data, in-hospital evaluation, neurological severity and TOAST classification, treatment, and the modified Rankin Scale (mRS) score of patients were assessed. Early neurological deterioration was defined as an increase of ≥2 points in the National Institutes of Health Stroke Scale score between the baseline and 72-hour evaluation. Favorable and poor outcomes were defined as mRSs of 0–2 and ≥3, respectively, at 3 months. The incidence and risk factors were evaluated by univariate and multivariate regression analysis (step-back method). Results: The analysis included 455 subjects with an acute posterior circulation non-cardiac ischemic stroke, 330 (72.53%) of them male, with an average age of 63.12 (±10.14) years and with 47 (10.33%) having END. The results of univariate and multivariate logistic regression analysis showed that BATMAN scores ≥5 (OR: 0.1, 95% CI: 0.02–0.53, P < 0.01), large artery atherosclerosis (OR: 11.55, 95% CI: 4.18–31.93, P < 0.01), vascular stenosis >50% (OR: 2.44, 95% CI: 1.1–5.42, P = 0.029), reperfusion therapy (OR: 4.21, 95% CI: 1.66–10.64, P < 0.01), and the distribution of pontine lesions (OR: 5.66, 95% CI: 2.39–13.44, P< 0.01) were significantly associated with END. Patients with END had a lower rate of favorable outcomes at discharge and long-term follow-up (P < 0.001), regardless of whether they received reperfusion therapy. Conclusion: The lesion distribution of the pons, the progression of temporo-occipital lobe lesions, and large arterial atherosclerosis are independent risk factors of END that might predict a poor short- and long-term prognosis.

Sixteen species of the genus Formicococcus (Hemiptera: Coccomorpha: Pseudococcidae) are recognized from China. Among them, a new species, F. delonicola Zhang & Wu sp. n., is described and illustrated based on adult females collected from Xishuangbanna, Yunnan, China on Delonix regia (Fabaceae). The new species is similar to Formicococcus latens Williams 2004 in possessing oral collar tubular ducts on the head and in marginal groups on the posterior abdominal segments. However, it differs from the latter in the morphological character states of dorsal setae on abdominal segment VIII, anal ring setae length and tips morphology of cerarian setae. The monotypic genus Anaparaputo Borchsenius 1962 is recognized as a junior synonym of Formicococcus, and Anaparaputo liui Borchsenius 1962 is transferred to Formicococcus as Formicococcus liui (Borchsenius 1962) comb. n. Three species, Paraputo bambusus (Wu 2001), Paraputo eriobotryae (Wang 1985) and Planococcus mumensis Tang 1977 are here restored to Formicococcus, as F. bambusus (Wu 2001) comb. rev., F. eriobotryae Wang 1985 comb. rev. and F. mumensis (Tang 1977) comb. rev. respectively, bringing the number of Formicococcus species found in China to 16. A key to the Palaearctic and Oriental species of Formicococcus is provided.

This study aimed to focus on the high-value utilization of raw wheat gluten by determining the potent antioxidant peptides and angiotensin I-converting enzyme (ACE) inhibitory peptides from wheat gluten oligopeptides (WOP). WOP were analyzed for in vitro antioxidant activity and inhibition of ACE, and the identification of active peptides was performed by reversed-phase high-performance liquid chromatography and mass spectrometry. Quantitative analysis was performed for highly active peptides. Five potent antioxidant peptides, Leu-Tyr, Pro-Tyr, Tyr-Gln, Ala-Pro-Ser-Tyr and Arg-Gly-Gly-Tyr (6.07 ± 0.38, 7.28 ± 0.29, 11.18 ± 1.02, 5.93 ± 0.20 and 9.04 ± 0.47 mmol 6-hydroxy-2,5,7,8-tetramethylchroman-2-carboxylic acid (Trolox) equivalent/g sample, respectively), and five potent ACE inhibitory peptides, Leu-Tyr, Leu-Val-Ser, Tyr-Gln, Ala-Pro-Ser-Tyr and Arg-Gly-Gly-Tyr (half maximal inhibitory concentration (IC50) values = 0.31 ± 0.02, 0.60 ± 0.03, 2.00 ± 0.13, 1.47 ± 0.08 and 1.48 ± 0.11 mmol/L, respectively), were observed. The contents of Leu-Tyr, Pro-Tyr, Tyr-Gln, Ala-Pro-Ser-Tyr, Arg-Gly-Gly-Tyr, and Leu-Val-Ser were 155.04 ± 8.36, 2.08 ± 0.12, 1.95 ± 0.06, 22.70 ± 1.35, 0.25 ± 0.01, and 53.01 ± 2.73 μg/g, respectively, in the WOP. Pro-Tyr, Tyr-Gln, Ala-Pro-Ser-Tyr, Arg-Gly-Gly-Tyr, and Leu-Val-Ser are novel antioxidative/ACE inhibitory peptides that have not been previously reported. The results suggest that WOP could potentially be applied in the food industry as a functional additive.

Our aim is to investigate whether vascular risk factors are associated with cerebral deep medullary veins (DMVs) and whether DMVs are associated with MRI markers of cerebral small vessel disease (CSVD) or risk of stroke. In a community-based cohort of 1056 participants (mean age 55.7 years), DMVs were identified on susceptibility-weighted imaging (SWI) and counted in periventricular regions. Neuroimaging markers including lacunes, whiter matter hyperintensity (WMH), microbleeds, enlarged perivascular space, and brain atrophy were evaluated. The number of DMVs decreased with age (p = 0.007). After adjusting for age and sex, the number of DMVs was not associated with traditional vascular risk factors. Fewer DMVs was associated with increase of WMH and lacunes, but the association vanished after adjustment for vascular risk factors. However, fewer DMVs were independently associated with brain atrophy (p

In this study, we examined the thermal effects throughout the process of the placement of span-scale girder segments on a 6×110-m continuous steel box girder in the Hong Kong-Zhuhai-Macao Bridge. Firstly, when a span-scale girder segment is temporarily stored in the open air, temperature gradients will significantly increase the maximum reaction force on temporary supports and cause local buckling at the bottom of the girder segment. Secondly, due to the temperature difference of the girder segments before and after girth-welding, some residual thermal deflections will appear on the girder segments because the boundary conditions of the structure are changed by the girth-welding. Thirdly, the thermal expansion and thermal bending of girder segments will cause movement and rotation of bearings, which must be considered in setting bearings. We propose control measures for these problems based on finite element method simulation with field-measured temperatures. The local buckling during open-air storage can be avoided by reasonably determining the appropriate positions of temporary supports using analysis of overall and local stresses. The residual thermal deflections can be overcome by performing girth-welding during a period when the vertical temperature difference of the girder is within 1 °C, such as after 22:00. Some formulas are proposed to determine the pre-set distances for bearings, in which the movement and rotation of the bearings due to dead loads and thermal loads are considered. Finally, the feasibility of these control measures in the placement of span-scale girder segments on a real continuous girder was verified: no local buckling was observed during open-air storage; the residual thermal deflections after girth-welding were controlled within 5 mm and the residual pre-set distances of bearings when the whole continuous girder reached its design state were controlled within 20 mm.

This paper aims to address the problem of geometric state control of large-segment steel box girders in offshore hoisting during the construction of large-span bridges. First, the geometric state control indexes of a large-segment steel box girder are determined, such as the manufacturing parameters of the top and bottom slabs, the width of the annular joint, and the support position. Second, the geometric state equations and state transfer matrixes of large-segment steel box girders under different conditions are deduced by taking the mileage and elevation of control points as basic state variables. In application of the geometric state transfer method in the construction control of the Hong Kong-Zhuhai-Macao Bridge, the width of the annular joint and the position parameters for the support of the large-segment steel box girder are predicted precisely. Moreover, the manufacturing parameters of the top and bottom slabs of the steel box girders are calculated reliably. The measured values show that the width of the annular joint is basically the same with the difference of less than 2 mm, the eccentricity of bridge support is less than 20 mm, and the elevation error of the bridge deck is within −10 mm to +15 mm, which meets the construction accuracy. Using the geometric state transfer method, the rapid and accurate installation of the Hong Kong-Zhuhai-Macao Bridge has been realized, demonstrating that the precise control of the geometric state of a steel box girder with ectopic installation and multi-state transition can be realized by using the geometric state transfer method.

Background and Purpose: To compare the risk factors and risk of stroke between lacune and large perivascular spaces (PVSs) in a community-based sample. Methods: Large PVSs were assessed using 3.0T MRI in a population-based cohort consisting of 1,204 participants. The relationship between cardiovascular risk factors, neuroimaging changes, and incidental stroke risk and the presence of lacune or large PVSs was assessed with univariate and multivariable ordinal logistic regression analysis. Results: Of the 1,204 study participants (55.7 ± 9.3 years, 37.0% men), a total of 347 large PVSs were detected in 235 (19.5%) subjects, while a total of 219 lacunes were detected in 183 subjects (15.2%). The presence of lacunes was found to be significantly associated with age, male gender, hypertension, and diabetes, whereas only age (p < 0.01) and ApoEε4 carrier status (p < 0.01) were related to the presence of large PVSs. Those who had lacunes detected on MRI at baseline had a significant increased risk of stroke (hazard ratio [HR] 4.68; 95% confidence interval [CI], 1.15–19.07) during the 3-year follow-up independent of age, gender, and other vascular risk factors. However, there was no significant relationship between the presence of large PVSs and incident stroke (HR 3.84; 95% CI, 0.82–18.04). Conclusions: The lack of association between large PVSs and cardiovascular risk factors or risk of stroke indicated a nonvascular pathogenic mechanism underlying large PVSs, suggesting the importance of distinguishing large PVSs from lacunes in clinical practice.

Background: Cancer is one of the leading causes of pathological death in humans. Although CTHRC1 is a prooncogene highly expressed in a variety of tumor tissues, the specific biological mechanisms of CTHRC1 involvement in cancer development need to be elucidated. Methods: In the present study, nine online bioinformatics databases were employed to explore the potential prognostic and grading value of CTHRC1 in generalized cancer as well as its potential role in regulating tumor immunity. Results: Data from GEPIA2.0, Oncomine, TNMplot, Kaplan-Meier Plotter and TISIDB database had consistently demonstrated that CTHRC1 was associated with the expression, prognosis and typing in most cancer tissues. Cbioportal and SMART analysis revealed that genomic changes and methylation of CTHRC1 in most tumor tissues. Finally, Sangerbox and TIMER database analysis suggested that CTHRC1 was involved in the changes of immune cell components in tumor immune microenvironment, with certain heterogeneity. Meanwhile, CTHRC1 was correlated with TMB, MSI, neoantigen and tumor immune checkpoint, especially CD276. Conclusion: CTHRC1 had the potential as a prognostic and grading molecular marker for pan-cancer. And CTHRC1-related targeting agents may be a novel breakthrough in tumor immunotherapy.

Methylglyoxal (MGO), an endogenous reactive carbonyl compound, plays a key role in the pathogenesis of diabetic neuropathy. The aim of this study is to investigate the role of MGO in diabetic itch and hypoalgesia, two common symptoms associated with diabetic neuropathy. Methods: Scratching behavior, mechanical itch (alloknesis), and thermal hypoalgesia were quantified after intradermal (i.d.) injection of MGO in naive mice or in diabetic mice induced by intraperitoneal (i.p.) injection of streptozotocin (STZ). Behavioral testing, patch-clamp recording, transgenic mice, and gene expression analysis were used to investigate the mechanisms underlying diabetic itch and hypoalgesia in mice. Results: I.d. injection of MGO evoked dose-dependent scratching in normal mice. Addition of MGO directly activated transient receptor potential ankyrin 1 (TRPA1) to induce inward currents and calcium influx in dorsal root ganglia (DRG) neurons or in TRPA1-expressing HEK293 cells. Mechanical itch, but not spontaneous itch was developed in STZ-induced diabetic mice. Genetic ablation of Trpa1 (Trpa1-/- ), pharmacological blockade of TRPA1 and Nav1.7, antioxidants, and mitogen-activated protein kinase kinase enzyme (MEK) inhibitor U0126 abrogated itch induced by MGO or in STZ-induced diabetic mice. Thermal hypoalgesia was induced by intrathecal (i.t.) injection of MGO or in STZ-induced diabetic mice, which was abolished by MGO scavengers, intrathecal injection of TRPA1 blockers, and in Trpa1-/- mice. Conclusion: This study revealed that Nav1.7 and MGO-mediated activation of TRPA1 play key roles in itch and hypoalgesia in a murine model of type 1 diabetes. Thereby, we provide a novel potential therapeutic strategy for the treatment of itch and hypoalgesia induced by diabetic neuropathy.

Itch is a common symptom of skin diseases and significantly reduces patients' quality of life. Melatonin has anti-inflammatory and antioxidant effects. Our study examined the potential anti-itch effects of melatonin (N-acetyl-5-methoxytryptamine) in mice.We detected the effects of melatonin and its receptors on acute and chronic itch by conducting itching behavioral experiments in male C57 mice. Reactive oxygen species (ROS) levels and calcium ion (CaWe discovered that compound 48/80 (C48/80)- and chloroquine (CQ)-induced scratching were significantly decreased by intraperitoneal (i.p), intradermal, and intrathecal administration of melatonin in a dose-dependent manner in mice, and the co-administration of melatonin receptor antagonists abolished the anti-itch effects of i.d melatonin. The incubation of melatonin significantly decreased the intracellular ROS levels induced by C48/80 and CQ in cultured ND7/23 cells from a mouse x rat hybridoma nerve as neuron. Melatonin inhibited intracellular CaCollectively, our results indicate that melatonin attenuates acute and chronic itch, possibly via melatonin receptors, and its antioxidant, and anti-inflammatory effects in mice.

The arsenic in livestock wastewater would induce adverse impact on the biological treatment technology such as anaerobic ammonium oxidation (anammox) process. Extracellular polymeric substances (EPS) play an important role in resisting such toxicity. Unfortunately, the role of EPS in protecting anammox from As(III) and the mechanisms underlying the protection still remains unclear. This work comprehensively evaluated the acute toxicity of arsenic on anammox sludge and investigated the binding property and interaction mechanism. The results revealed that the half maximal inhibitory concentration (IC50) of As(III) on anammox sludge was estimated to be 408 mg L−1, which decreased to 41.97 mg L−1 when EPS was exfoliated. Complexation and hydrophobic interactions were the leading forces in preventing arsenic invasion. Protein was the main component that complexes with As(III), and O–H, –NH, –C O were binding sites. The response sequence of organic component in EPS to As(III) was ordered as hydrocarbons-proteins-polysaccharides-aliphatic amines.

To explore the combined effect of recombinant human transforming growth factor-β1 (rhTGF-β1) and recombinant human platelet derived growth factor-BB (rhPDGF-BB) on the expression of Pyk2 in the osteoclasts of the pressure side of orthodontic tooth in rats.One hundred and sixty male Sprague-Dawley rats were randomly divided into 2 groups: experimental group(A) and control group(B) to establish orthodontic tooth movement model. Rats in the experimental group received combined injection of 5 ng rhTGF-β1 and 10 ng rhPDGF-BB in the buccal submucosal area of the left upper first molar every other day, while rats in the control group received equivalent volumes of PBS. Rats in each group were sacrificed at each of 5 time points(1,4,7,10 and 14 days) after appliance placement. The distance of the tooth movement was measured with stereomicroscope, the change of the amount of osteoclasts was detected with tartrate-resistant acid phosphatase histochemistry (TRAP), the protein and mRNA expression of Pyk2 was detected by immunohistochemistry and real time PCR(RT-PCR). SPSS19.0 software package was used for statistical analysis.The distance of teeth in group A moved more rapidly than in group B, except for the first day, significant differences were found (P0.05) in all time points.The number of osteoclasts in group A was significantly higher than that in group B, except for the 14th day, compared with the control group(P0.05). Pyk2 protein and gene expression of group A was significantly higher than group B, both groups reached a peak in 7 days and gradually decreased thereafter, except in the first day, the expression of protein Pyk2 was significantly different at other time points (P0.05).rhTGF-β1 and rhPDGF-BB up-regulated the expression of Pyk2 protein and mRNA gene on the pressure side of orthodontic tooth in rats, which may be one of the reasons for accelerating the rate of orthodontic tooth movement.

Sulfide has attracted increasing attention due to its odor nuisance, toxicity and corrosion. Although variations in the nitrogen removal performance of anammox under sulfide stress have been reported previously, understanding the microorganisms at the molecular level is of greater significance. This study first deciphered the microbial community and functional gene response of anammox sludge to sulfide stress. Results showed that 20 mg L−1 sulfide could reduce specific anammox activity by 61.7%. The protein-like substances within extracellular polymeric substances were quenched at the end of the experiment. Moreover, the relative abundance of Candidatus Kuenenia significantly decreased from 28.7% to 6.4% while Thiobacillus increased from 0 to 7.2% due to sulfide stress. Furthermore, the abundances of functional genes (hzsA, hdh, nirK and nirS) significantly decreased when the sulfide concentration reached 20 mg L−1. These findings provide a further theoretical basis for the anammox process for nitrogen removal from wastewater containing sulfide.

Anaerobic ammonium oxidation (anammox) process exhibits advantages in treating high-ammonium livestock wastewater, while the anammox bacteria is vulnerable to heavy metal and antibiotics. Arsenic and sulfonamides extensively existed in livestock wastewater; unfortunately, their effects on the anammox process have not yet been investigated. This work comprehensively evaluated the single and joint effects of As(III) and sulfamethoxazole (SMX) on the anammox process and revealed the related inhibitory mechanism. Anammox had extraordinary resistance to As(III) stress (0–50 mg L−1), while nitrogen removal sharply deteriorated under the stress from 50 mg L−1 As(III) and 3 mg L−1 SMX. Exogenous As(III) damaged the protection of extracellular polymeric substance (EPS) and aggravated the inhibition of SMX. As(III) had direct toxic effects on anammox bacteria, while enhanced denitrifying capacity was the reason for inhibition of anammox by SMX. Moreover, the host arsenic resistance genes were changed under SMX inhibition. The findings of this study enrich our knowledge of the anammox response to various pollutants, and provide the operational guidance for anammox process to treat wastewater containing antibiotic and heavy metal.

A study of the genus Paraputo Laing, 1929 (Coccomorpha: Pseudococcidae) from China is provided. Eight Paraputo species are recognized in China, of which two species, P. platani sp. n. and P. yunnanensis sp. n., are described as new and P. banzigeri Williams, 2004 is recorded from China for the first time. Two new combinations are introduced, involving transfer of P. citricola Tang, 1992 and P. sinensis Borchsenius, 1962 to the genus Formicococcus Takahashi, 1928. A key to the Paraputo species of China is provided.

Background Parkinsonism-related motor complaints are commonly seen in the elderly. Our study aimed to investigate the association among Parkinsonism-related motor complaints, cerebral small vessel disease and cerebrovascular risk factors in a community-dwelling population in a Chinese rural area.Methods Individuals who were 50 years old or older, were independently living, were well-functioning, and had no history of ischemic or hemorrhagic stroke, were included. Brain magnetic resonance imaging (MRI), quantified motor function assessment, and questionnaire screening for Parkinsonism-related motor complaints were performed. Clinical data including cerebrovascular risk factors were collected. In univariate analysis, Chi-square test and student t-test were used to compare dichotomous variables and continuous variables, respectively, between individuals with or without motor complaints. In multivariate analysis, binary Logistic regression models were generated to determine risk factors for Parkinsonism-related motor complaints. General linear models were used to compare motor parameters between individuals with or without motor complaints. Results In the final analysis, 854 people were included. Individuals with motor complaints had a longer time for finger taping (6.2s v.s. 5.6s, p = 0.006), and a longer time for 3m-walking(4.0s v.s. 3.6s, p = 0.034) than did those without motor complaints. Hypertension was associated with motor complaints (odds ratio, 1.82; 95% confidence interval [CI], [1.21, 2.73]; p = 0.004). Age was not associated with motor complaints; none of the neuroimaging markers of cerebral small vessel disease was associated with motor complaints. Conclusion Hypertension is associated with Parkinsonism-related motor complaints. Better management of hypertension may prevent mobility limitation in the elderly. The questionnaire that we used for Parkinsonism is not suitable for screening small vessel disease in a community-dwelling population.

A modified viscoelastic constitutive model is proposed to predict cure-induced residual stresses in polymer matrix composites. The modifications rely on using the inverse of the Deborah number to describe regimes corresponding to a fully relaxed state, a viscoelastic state and an elastic state. The composite is only in a viscoelastic state for limited ranges of the Deborah number. By considering the evolution of the Deborah number during curing of the AS4/3501-6 composite, the composite is in a fully relaxed state when it is cured at high temperature and the degree of cure is lower than 0.73, and no further changes in the viscoelastic characteristics when the degree of cure is higher than 0.8. A 3D simulation of a composite laminate plate is used to predict the evolution of the residual stresses. The analysis reveals that the accurate simulation on the cure-induced residual stress should include the last two states of the entire cure process, and consider the stress relaxation, thermal deformation and chemical shrinkage.

Mealybugs (Hemiptera: Pseudococcidae) are an insect group that feeds on plant sap; many are major pests of ornamental plants and crops worldwide. The difficulty of morphological identification of mealybugs points to a need for a rapid and effective identification method, like DNA barcoding, to assist morphological taxonomy. Here, we employed diverse methods (best close match [BCM], Neighbor-Joining [NJ] tree, Barcoding with LOGic formulas [BLOG], Poisson Tree Process [PTP] Species Delimitation Method) to test the efficiency of two molecular markers (mitochondrial cytochrome c oxidase I [COI] and large ribosomal subunit gene [28S]) that could be used for species identification of 54 mealybug species that commonly occur in China. Two hundred six COI barcodes (47 species) and 242 28S sequences (53 species) were recovered from 246 individuals. In both the COI and 28S data sets, species except for Planococcus citri and P. minor were unambiguously identified by all the methods. The PTP analysis based on COI sequences generated more putative species in Antonina tesquorum , Atrococcus paludinus , and Formicococcus sp. than morphological identification. Among these three cases, the sequences of At. paludinus showed 3.55% variation at the 28S locus, possibly reflecting cryptic diversity in this taxon. Our study corroborates the utility of the COI and 28S genes in the rapid identification of mealybugs, and the barcode library we provide will create an effective identification system for mealybug pest management in China.

Environmental pollution by antibiotics has severely affected human health and development. Antibiotic resistance genes (ARGs) have also been recognized as emerging pollutants because of their persistence and adverse impacts in aquatic ecosystems, even at low concentrations. For the alleviation and elimination of antibiotics stress, several approaches have been proposed, some of which have been applied in practice. This review systematically summarizes the removal strategies for various antibiotics and their corresponding mechanisms, including chemical, physical, biological, condition-based and combined strategies. Moreover, a comparison among these methods is made with a focus on the performance and efficiency. Further research needs are also proposed, which provides a guidance for the establishment of a control strategy to achieve simultaneous removal of nitrogen, antibiotics and ARGs.

The mealybug genus Saccharicoccus Ferris includes three species: S. isfarensis (Borchsenius, 1949), S. sacchari (Cockerell, 1895) and a new species, S. chinensis Zhang, Wu & Wu sp. n. The new species, collected on Miscanthus sp. (Poaceae) and other poaceous weeds in China, is described and illustrated, and molecular analyses based on the mitochondrial gene cytochrome c oxidase subunit I (COI) are provided. Additional data on the distribution and host-plants of each species are given, and a key to the adult females of Saccharicoccus species is provided.

A new mealybug genus, Dorsoceraricoccus Dong & Wu gen. nov. (Hemiptera: Sternorrhyncha: Coccomorpha: Pseudococcidae), is described to contain Dysmicoccus muajatae Williams as type species, and a new species, Dorsoceraricoccus ningboensis Dong & Wu sp. nov., collected from Zhejiang Province, China on Digitaria sp. (Poaceae). For the new species, the adult female is described and illustrated. In addition, a key to genera of the subfamily Pseudococcinae now known from China and a key to adult female now in Dorsoceraricoccus gen. nov. are provided.

The kinetics of nitrogen absorption in Fe-Cr-Mn (Mo) alloys under 0.1 MPa nitrogen pressure and 1873K was investigated by top blowing nitrogen gas into the steel melts. A thermodynamic model of nitrogen solubility was established. Also the effect of surface active elements oxygen and sulfur on nitrogen absorption was studied. The results show that Fe-Cr-Mn (Mo) melts achieve nitrogen saturation value within 50 minutes, the nitrogen solubility increases with the content of chromium and manganese, but the experiment values of nitrogen solubility are general lower than theoretical values because of the open nitrogen gas atmosphere and high surface active elements content in the steel melts. The nitrogen absorption can be described well by a second order reaction and the interfacial reaction is restrictive step. The rate of nitrogen absorption decreases by lowering the surface reaction constant due to oxygen and sulfur in the steel melts. The effect of the surface active elements oxygen and sulfur on nitrogen absorption can be described well as .

A two-dimensional axisymmetric model was constructed to predict the ablation of the insulation layer in an end burning rocket motor by using the Computational Fluid Dynamics (CFD) software Fluent. The insulation material of graphite was used in the model. The wall surface reactions and discrete phase erosion were applied to simulate the insulation layer ablation. The influence of the burning surface movement was analyzed by using the dynamic mesh method. Numerical results show that the erosion rate increase with the increasing of burning time. The maximum erosion rate occurs at the upstream of the nozzle throat. There has a high erosion rate closing to the burning surface, and it decreases gradually away from the burning surface and becomes zero near the nozzle. It’s found that solid particle deposition appears on the inner surface of combustor closing to the nozzle, and it increases with the increasing of time.