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To describe the need for high school sleep education from the perspective of undergraduate university students. Undergraduate students who completed an online course on sleep and circadian health were surveyed 6 months after course completion. Students were asked whether a similar course would have benefited them as high school students, and about the need for sleep education in high schools. Thematic analysis of this qualitative data was carried out. Eighty‐nine students who had attended 71 unique high schools provided responses. Eight‐one per cent thought they would have benefitted from a similar course during high school and identified domains of sleep knowledge particularly relevant to high school students. They cited environmental barriers to healthy sleep present during high school and believed that sleep education could improve students’ lifestyle, sleep and performance. Nineteen per cent of students said they would not have benefited, because they perceived sleeping patterns during high school to be nonmodifiable or believed that previous sleep education was sufficient. Of the respondents who did not think students would benefit, 53% would still tell their high school principal that there was a need for sleep education. The findings support the need for engaging sleep education for high school students. Future studies should examine the perspectives of students in high school directly, rather than undergraduate students who have already shown an interest in sleep health. Sleep health is missing from the Australian school curriculum. Online courses may be an engaging method of promoting sleep and circadian health to high school students.

To elucidate whether Bronze Age population dispersals from the Eurasian Steppe to South Asia contributed to the gene pool of Indo-Iranian-speaking groups, we analyzed 19,568 mitochondrial DNA (mtDNA) sequences from northern Pakistani and surrounding populations, including 213 newly generated mitochondrial genomes (mitogenomes) from Iranian and Dardic groups, both speakers from the ancient Indo-Iranian branch in northern Pakistan. Our results showed that 23% of mtDNA lineages with west Eurasian origin arose in situ in northern Pakistan since ~5000 years ago (kya), a time depth very close to the documented Indo-European dispersals into South Asia during the Bronze Age. Together with ancient mitogenomes from western Eurasia since the Neolithic, we identified five haplogroups (~8.4% of maternal gene pool) with roots in the Steppe region and subbranches arising (age ~5–2 kya old) in northern Pakistan as genetic legacies of Indo-Iranian speakers. Some of these haplogroups, such as W3a1b that have been found in the ancient samples from the late Bronze Age to the Iron Age period individuals of Swat Valley northern Pakistan, even have sub-lineages (age ~4 kya old) in the southern subcontinent, consistent with the southward spread of Indo-Iranian languages. By showing that substantial genetic components of Indo-Iranian speakers in northern Pakistan can be traced to Bronze Age in the Steppe region, our study suggests a demographic link with the spread of Indo-Iranian languages, and further highlights the corridor role of northern Pakistan in the southward dispersal of Indo-Iranian-speaking groups.

A novel redox-active Schiff base polymer (SBPPPDA-PDA) was prepared by condensation of p-phenylenediamine with 1,10-phenanthroline-2,9-dicarbaldehyde. The structure of SBPPPDA-PDAwas investigated by scanning electron microscopy, transmission electron microscopy, atomic force microscopy, Fourier transform infrared spectroscopy, N2adsorption/desorption isotherm, and powder X-ray diffraction and electrochemical techniques. The results showed that SBPPPDA-PDAhad two-dimensional lamellar structure. The electrochemical properties of SBPPPDA-PDAwere characterized by cyclic voltammetry, showing several pairs of redox peaks and good catalytic ability toward oxygen reduction. On the basis of the redox-active activity of SBPPPDA-PDA, an electrochemical pH sensor was proposed based on SBPPPDA-PDAwith a linear range from 2 to 9 for pH detection. With nitrogen-containing skeleton and porous structure, SBPPPDA-PDAcould be used as support to load glucose oxidase (GOD). Thus, a novel ratiometric electrochemical glucose sensor was further constructed by immobilizing GOD on SBPPPDA-PDAmodified electrode. The results revealed that the reduction peak of O2decreased with the gradual addition of glucose, while the response peak of SBPPPDA-PDAat about 0.15 V almost remained. The sensor based on GOD/SBPPPDA-PDA/SPE showed a rapid response, a linear range from 22.5 μmol/L–5 mmol/L and a lower detection limit of 7.56 μmol/L for glucose.

The smoothing function is used to solve the problem of low simulation efficiency of multi-stage stiffness Dual Mass Flywheel (DMF) model, and the influence of different smoothing functions and fitting factor βon the fitting effect is studied. Firstly, based on the analysis of the working principle of multi-stage stiffness DMF, a mathematical model of DMF considering multi-stage stiffness and damping nonlinearity is established, and the accuracy of the model is verified by bench test. Then, tanh function, arctangent function, and sigmoid function are used to smooth the segment points in the DMF model, which solves the problem of inefficiency and not easy to converge in simulation. Finally, a 3-DOF model of the transmission system with DMF is established to simulate and analyze the smooth effect of the smoothing function and the performance difference between different smoothing functions. The results show that the smoothing function can effectively improve the stability of the simulation model. By comparing the three smoothing functions, it can be seen that the sigmoid function has the most obvious effect, which can shorten the simulation time by 52%.

ABSTRACTThe screening and treatment of laryngeal squamous cell carcinoma (LSCC) still perplexes clinicians, making it necessary to explore new markers. To this end, this research examined the underlying molecular mechanism of LSCC based on high-throughput datasets (n= 249) from multiple databases. It also identified transcription factors (TFs) independently associated with LSCC prognosis. Through Gene Ontology and Kyoto Encyclopedia of Genes and Genomes analyses, differential expression genes of LSCC were deemed relevant to the extracellular matrix and its related structures or pathways, suggesting that the extracellular matrix plays an important role in LSCC. At the same time, several hub genes that may also have important roles in LSCC were identified via protein–protein interaction analysis, including CDC45, TPX2, AURKA, KIF2C, NUF, MUC1, MUC7, MUC4, MUC15,and MUC21. Eight unreported LSCC prognostic TFs – BCAT1, CHD4, FOXA2, GATA6, HNF1A, HOXB13, MAFF,and TCF4– were screened via Kaplan–Meier curves. Cox analysis determined for the first time that HOXB13expression and gender were independently associated with LSCC prognosis. Compared to control tissues, elevated expression of HOXB13was found in LSCC tissues (standardized mean difference = 0.44, 95% confidence interval [0.13–0.76]). HOXB13expression also makes it feasible to screen LSCC from non-LSCC (area under the curve = 0.77), and HOXB13may play an essential role in LSCC by regulating HOXB7. In conclusion, HOXB13may be a novel marker for LSCC clinical screening and treatment.

ABSTRACTSynaptotagmins (SYTs), constitute a family of 17 membrane-trafficking protein, palying crucial roles in the development and progression of human cancers. However, only very few studies have investigated the expression profile and prognostic values of SYTs family members in gastric cancer (GC). Therefore, we comprehensively evaluated the expression, methylation, prognosis and immune significance of SYTs family members through bioinformatics analysis from the online databases in GC. The expressions of SYT4, SYT9, and SYT14 were up-regulated, and negatively associated with their methylation levels in GC. Both the over-expression of SYT4, SYT9 and SYT14 and their hypomethylation levels contributed to an unsatisfactory overall survival (OS) and progression-free survival (PFS) in GC. Moreover, the low expressions of several methylation cg sites (cg02795029, cg07581146, cg15149095, cg19922137, cg25371503, cg26158959, cg02269161, cg03226737, cg08185661, cg16437728, cg22723056 and cg24678137) were significantly correlated with an unfavorable OS and PFS in GC. Furthermore, the expression of SYT4, SYT9 and SYT14 played a pivotal role in immune cells infiltration in GC. Collectively, our current finding suggested that SYT4, SYT9 and SYT14 might be potent prognostic indictors and promising immunotherapeutic targets for GC patients.

Sildenafil citrate is approved to treat erectile dysfunction. An orally disintegrating tablet (ODT) of sildenafil citrate that does not require swallowing or administration with fluids has been developed. The bioequivalence and bioavailability of sildenafil citrate ODT (50 mg) without and with water were compared with conventional sildenafil citrate tablets (50 mg) in an open‐label, randomized crossover study. Healthy Chinese male subjects (n = 36) were allocated to 1 of 6 sildenafil citrate treatment sequences under fasted conditions, and plasma samples for determination of sildenafil concentrations were collected predose through 14 hours postdose. Bioequivalence was demonstrated for sildenafil citrate ODT administered without water relative to the sildenafil citrate tablet administered with water; 90%CIs for the ratios of adjusted geometric means for sildenafil AUClast, Cmax, and AUCinf(ratio, 101.41%; 90%CI, 95.49%‐107.70%; ratio, 93.55%; 90%CI, 84.15%‐104.00%; and ratio, 101.03%; 90%CI, 94.80%‐107.66%; respectively) were wholly contained within the bioequivalence acceptance range of 80% to 125%, indicating bioequivalence criteria were met. Relative bioavailability of sildenafil citrate ODT administered with water to the sildenafil citrate tablet (50 mg) administered with water was 97.10%, 91.43%, and 97.09% with respect to sildenafil AUClast, Cmax, and AUCinf, respectively (90%CI, 91.43%‐03.12%, 82.25%‐101.65%, and 90.90%‐103.71%, respectively). Both sildenafil citrate formulations were generally well tolerated in healthy Chinese men. Sildenafil citrate ODT administered without or with water was bioequivalent to or met bioequivalence criteria compared with conventional sildenafil citrate tablets administered with water under fasted conditions in healthy Chinese men, thus offering a convenient alternative method of oral administration.

Graphical Abstract

Organosulfates (OSs) derived from biogenic volatile organic compounds are important compounds signifying interactions between anthropogenic sulfur pollution and natural emission. In this work, we substantially expand the OS standard library through the chemical synthesis of 26 α-hydroxy OS standards from eight monoterpenes (i.e., α- and β-pinene, limonene, sabinene, Δ3-carene, terpinolene, and α- and γ-terpinene) and two sesquiterpenes (i.e., α-humulene and β-caryophyllene). The sulfation of unsymmetrically substituted 1,2-diol intermediates produced a regioisomeric mixture of two OSs. The major regioisomeric OSs were isolated and purified for full NMR characterization, while the minor regioisomers could only be determined by liquid chromatograph–mass spectrometer (MS). The tandem mass spectra of the molecular ion formed through electrospray ionization confirmed the formation of abundant bisulfate ion fragments (m/z97) and certain minor ion fragments characteristic of the carbon backbone. A knowledge of the MS/MS spectra and chromatographic retention times for authentic standards allows us to identify α-hydroxy OSs derived from six monoterpenes and β-caryophyllene in ambient samples. Notably, among two possible regioisomers of α-hydroxy OSs, we only detected the isomers with the sulfate group at the less substituted carbon position derived from α-pinene, limonene, sabinene, Δ3-carene, and terpinolene in the ambient samples. This observation sheds light on the atmospheric OS formation mechanisms.

In order to know if any protein encoded by citrus vein enation virus (CVEV) might act as an RNA silencing suppressor (RSS), five open reading frames (ORF) of CVEV, including the coat protein (CP) gene, were individually cloned into the binary expression vector pBI121. The silencing suppression ability of the five ORFs was tested by ‘viral minireplicon infectivity assays’ based on a beet yellows virus (BYV) minireplicon carrying a reporter gene (BYVminiR-GFP). GFP imaging and microscopic analyses were used to observe whether RNA silencing suppression occurred or not. In addition, real-time quantitative RT-PCR was used to quantify the mRNA expression of GFP in the injected region. The fluorescence intensity of leaves with CP expression was stronger than that of the empty vector negative control, but it was weaker than that of the positive control HC-Pro of tobacco etch virus (TEV), indicating that the CP of CVEV partly inhibited the GFP gene silencing. Co-expression of each of the other four ORFs with BYVminiR-GFP showed an almost complete quenching of GFP fluorescence in infiltrated areas, similar to that of the negative control. The amount of GFP mRNA in the leaves co-expressed with CP was nearly twice as much as that of either the negative control or other ORFs. These results suggest that CP of CVEV is a weak gene silencing suppressor.

Dihydromyricetin (DMY), hyperoside and silybin are phytochemicals that belong to a class called flavonoids, and they have been used in liver protection pharmaceutical preparations, but the specific mechanism of these chemicals is still unclarified. This study aims to investigate the hepatoprotective effects and potential mechanism of these phytochemicals. The immortalized human hepatocyte cell line L02 was treated with 200 μM emodin for 48 h, and this was used as a hepatocyte injury model. The L02 cells were treated with both 200 μM emodin and different concentrations of DMY/hyperoside/silybin for 48 h to investigate the protective effects of these phytochemicals. The CCK-8 assay was used to detect cell viability. RT-qPCR and western blotting were performed to examine the mRNA and protein expression, respectively, of the classic bile acid synthetic pathway gene CYP7A1, the bile acid efflux transporter bile salt export pump (BSEP), the nuclear factor erythroid-2-related factor 2 (Nrf2) and the drug processing gene CYP1A2. DMY, hyperoside and silybin prevented the impairment of cell viability that was caused by emodin-induced hepatotoxicity in a dose-dependent manner, and at a low concentration (10 μM), the protective effect followed the order hyperoside > DMY > silybin, while at a high concentration (160 μM), the protective effect followed the order DMY > hyperoside > silybin. These phytochemicals reduced the expression of CYP7A1 at both the mRNA and protein levels. BSEP was not influenced by the phytochemical intervention. When 200 μM emodin was used for 48 h with the addition of the phytochemicals at 200 μM, the nuclear protein expression of Nrf2 significantly increased and CYP1A2 expression decreased. DMY, hyperoside and silybin prevented the hepatotoxicity induced by emodin in the L02 cells, potentially, viathe Nrf2 signaling pathway.

Describe sleep duration in adult Sri Lankans and determine the bias and agreement of self-report and actigraphic assessments.

Sleep is important for the physical, social and mental well-being of both children and adults. In this paper, we discuss the need to consider sleep as a multidimensional construct and as a component of total 24-hour activity. First, we make a case for considering sleep as a multidimensional construct, whereby all characteristics of sleep (including duration, quality, timing, and variability) and their links with health are examined. Second, we argue that sleep should also be conceptualized as part of the daily spectrum of time-use, along with other types of activity. We propose novel statistical models, in particular compositional data analysis (CoDA), as appropriate analytical methods for a new sleep paradigm.

We aimed to evaluate the interaction of two key determinants of sleep health, quantity and quality, with physical, emotional, and social functioning, in the general population.

C12H9ClFN3, monoclinic, P21/n(no. 14), a= 10.120(4) Å, b= 13.823(6) Å, c= 16.480(7) Å, β= 91.744(8)°, V= 2304.4(17) Å3, Z= 8, Rgt(F) = 0.0402, wRref(F2) = 0.0932, T= 113.15 K.

Sleep is important for the physical, social and mental well-being of both children and adults. Over the years, there has been a general presumption that sleep will inevitably decline with the increase in technology and a busy 24-hour modern lifestyle. This narrative review discusses the empirical evidence for secular trends in sleep duration and the implications of these trends.

The rock-breaking mechanism and effect of confined blasting were analysed by blasting and impact dynamic mechanics, fluid dynamic mechanics, fracture mechanics as well as blasting experiment. The results showed that the fracturing of surrounding rock in confined blasting condition is the result of coaction of rock pre-cracking by shock wave and stress wave and the continuing expanding crack-enhancement of confined medium, and the model of crack development of borehole surrounding rock in confined blasting condition was established. This study acquired the damage range of surrounding rock under the action of shock wave and stress wave, as well as the crack development characteristics of surrounding rock after the wedge-in confined medium into the crack space. Deep-hole confined blasting experiment on large rock showed that the high-efficient utilisation of in-hole explosive was achieved and the safety of rock blasting operation was ensured. Safe static rock-breaking under the action of high-efficient explosive blasting was achieved as well as the unification of super dynamic load of explosive blasting and static rock-breaking of water medium.

Asthma has become the serious chronic and the most common disease of hospitalization in children. Recently, the number of children with asthma has increased year by year. Thereafter, the medical community pays much attention to the treatment of asthma. Because of noises or outlier, the resulting factors for asthma are complex. Traditional algorithms usually assume that asthma data are evenly distributed among various classes and might ignore minority classes. Therefore, an intelligent algorithm based on bacterial foraging optimization (BFO) and robust fuzzy algorithm (RFA) is applied to analyze asthma data in this paper. In the proposed algorithm, RFA with the property of robust can reduce the influence of noises or outlier. It can establish the fuzzy model and effectively analyze asthma data. For foraging theory, natural selection trends to eliminate animals with poor foraging strategies and to favor the propagation of genes for animals which have successful foraging strategies. BFO can model the mechanism of natural selection and find the best solution. Consequently, it can enhance the classification accuracy of asthma data. In this paper, asthma data were collected from Mackay Memorial Hospital in Taiwan to test the performance of the proposed algorithm. The performance of the proposed algorithm is supported by simulation results. From simulation results, the classification accuracy of the proposed algorithm outperforms other existing approaches and can help physicians to determine asthma.

Although it is widely recognized that the ancestors of Native Americans (NAs) primarily came from Siberia, the link between mitochondrial DNA (mtDNA) lineage D4h3a (typical of NAs) and D4h3b (found so far only in East China and Thailand) raises the possibility that the ancestral sources for early NAs were more variegated than hypothesized. Here, we analyze 216 contemporary (including 106 newly sequenced) D4h mitogenomes and 39 previously reported ancient D4h data. The results reveal two radiation events of D4h in northern coastal China, one during the Last Glacial Maximum and the other within the last deglaciation, which facilitated the dispersals of D4h sub-branches to different areas including the Americas and the Japanese archipelago. The coastal distributions of the NA (D4h3a) and Japanese lineages (D4h1a and D4h2), in combination with the Paleolithic archaeological similarities among Northern China, the Americas, and Japan, lend support to the coastal dispersal scenario of early NAs.

A mobile ad hoc network is formed by a cluster of mobile stations randomly located within a certain area without the infrastructure of base stations. There have been many researches proposing different models of routing protocols and numerous simulations to enhance their performances under varying conditions and constraints. However, most of them only focus on network layer without considering the influence of media access control (MAC) layer. In this paper, a new strategy of cross layer algorithm is proposed based on the characteristics of reactive routing and multi-hop jumping. In addition, artificial bee colony algorithm is performed to calculate the contention window of the nodes along the routing path over MAC layer. This framework could avoid data collision in MAC layer, and results in getting better performances of data transmission in network layer. Extensive simulations show that the proposed AODV with intelligent priority flow scheme is able to earn a significant improvement over the conventional routing algorithm.

The Longfengtou Beach in the Haitan Bay, located in Fujian Province of China and facing the Haitan Strait, has been suffering severe erosion due to the construction of seawalls. A simple beach nourishment project implemented has not achieved the anticipated beach restoration. Thus a practical solution has to rely on a combination with near-shore marine structures. In this study, a 2-D calibrated flow model is set up to investigate the effects of three different layouts of near-shore marine structures on the tidal current. It is shown that the breakwaters situated in both the north and south ends play a vital part in the protection against erosion. The offshore breakwaters can serve as a barrier to obstruct the current circulation then reduce the current velocity. The groyne linking the Guimo islet and the coast significantly reduces the south-to-north water exchange through the channel and redirects the current direction nearly perpendicular to the north breakwater, which cuts off the longshore transport that may have a negative influence on the beach, especially, the northern part. It is also noted that the monsoon at the site with different directions increases the current velocity. In general, proper layouts of marine structures can reduce the current velocity thus lead to less intense sand transport near the beach.

Environmental contextChina has been experiencing severe particulate pollution and frequent haze episodes in recent years. We compare the molecular composition of urban organic aerosols on clear and hazy days in Beijing by high-resolution mass spectrometry. The comparative study shows that oxidation, sulfation and nitrification processes actively involve precursors of anthropogenic origin in the Beijing polluted urban atmosphere. AbstractHaze has frequently affected many cities and threatened human health in China. Detailed knowledge of the chemical composition of secondary organic aerosol provides fundamental information in the study of the formation mechanism of haze and its adverse effects on human health. In our work, dichloromethane and water extracts of ambient aerosols collected on hazy and clear days in Beijing were characterised by negative-ion electrospray ionisation and Fourier-transform ion cyclotron resonance mass spectrometry (FT-ICR MS). Formulae in four elemental compositional groups, namely CHOS, CHONS, CHO and CHON, were identified relying on the ultrahigh resolution and mass accuracy of FT-ICR MS. Significantly more compounds were detected and the peaks were much more intense in the hazy day samples, especially for the CHOS, CHONS and CHON formula groups. Organosulfates (OS) and nitrooxy-organosulfates (nitrooxy OS) were the major forms of CHOS and CHONS formulae respectively, and their numbers more than tripled on the hazy days. Under the severely polluted conditions in Beijing, the compositional distribution of the OS and nitrooxy OS exhibited distinct features such as intense peaks of low double-bond equivalent (DBE) (DBE=0, 1 for OS and DBE=1, 2 for nitrooxy OS) and low degree oxidation, of medium DBE (DBE=2, 3 for OS and DBE=3, 4 for nitrooxy OS), and of high DBE (DBE ≥ 4 for OS and DBE ≥ 5 for nitrooxy OS). The likely respective candidates for these could be aliphatic OS having a low degree of oxidation, biogenic OS and many aromatics and polycyclic aromatic hydrocarbon (PAH)-derived OS. The CHON formulae observed on hazy days were double those on clear days and had higher DBE values and larger O/N ratios. Slightly more CHO compounds were detected in the hazy-day samples and they had higher DBE values and more oxygen atoms. The comparative study suggests that oxidation, sulfation and nitrification processes actively involve precursors of anthropogenic origin in the Beijing polluted urban atmosphere.

The redundant spherical aberration of deformation can be caused by the weight of the stressed mirror polishing (SMP) apparatus in the continuous polishing (CP) process, and the elastic model to correct the spherical aberration by exerting center lateral loading is proposed. Subsequently, the analytic solution of mirror deformation is given by using a piecewise method. Next, the variation trend of mirror deformation with the loading force and the loading area size by the center lateral loading method is discussed. Following corresponding simulation calculation is carried out using finite element analysis (FEA) software. And the FEA result is compared with analytical solution. The experiment for the edge-loading force case is accomplished. Furthermore, a comparison between theoretical calculation and experiment results is provided. All of these verify the validity of the theoretical model and the analytic solution. Finally, we introduce another method called the bending mirror technique for correcting additional spherical aberration of mirror deformation, calculating and acquiring the optimum inner radius for bending and the corresponding surface residual error.

Commingling is employed in the petroleum industry to enhance oil recovery and reduce costs. It is of great importance to monitor the production of each oil well oilfields. Nowadays, more and more oilfields use chromatographic fingerprint to estimate single-zone production allocation. In order to insure the efficiency and affectivity of the commingled oil well exploiting, the productivity contribution of every single layer must be acquainted. Kernel partial least squares (KPLS) is a promising regression method for tackling nonlinear systems because it can efficiently compute regression coefficients in high-dimensional feature spaces by means of nonlinear kernel functions. Unlike other nonlinear partial least squares (PLS) techniques KPLS does not entail any nonlinear optimization procedures and has a complexity similar to that of linear PLS. Using the technology of crude oil chromatography fingerprint, an algorithm for predicting productivity contribution based on KPLS is proposed. The validity of the method is proved by laboratory artificial experiments. The maximum absolute error of predicted and real proportion is less than 10%. The model can also be applied to other wells which are similar to those used in the experiment. The experiment results show the prediction model is feasible.

Based on the derived bi-dimensional Bedrosian’s principles and the original multicomponents, we provide the combined bi-dimensional Bedrosian’s principle so that the monocomponents in multicomponents can be separated in the case that the existent methods fail. The proposed method can solve the problems caused by the cross-angle and amplitude ratio and frequency ratio and so on between these components that BEMD fails to solve. Experiments support the proposed methods.

In this paper, an approach is present to evaluate the inequity of the investment in transportation in China. The investment in the integrated transportation is expressed with transportation investment utility based on homogenized service. The approach evaluating the inequity is composited with four methods of inequity evaluation. This paper finds that the investment in transportation in China is poorly inequitable and four suggestions improving the equity of the transportation investment are proposed.

In this paper, an operational amplifier with low-power consumption has been designed. Using the complementary differential pair for the input stage and the class AB structure for the output stage, the common-mode input range and output swing of the proposed circuit could achieved rail-to-rail. Based on TSMC 0.18μm CMOS process, using HSPICE 2008 software for circuit simulation, the results showed that the proposed op-amp has more than 100dB open loop gain, meanwhile the static power consumption is less than 300μw. The circuit's phase margin is 68 degrees, CMRR is 135dB and power supply rejection ratio is 63dB.

CORDIC Algorithm is widely applicable to the hardware implementation of DSP, and it attaches a great importance in many hardware implementations of DSP for a lot of arithmetic operations are simplified to simple addition operations and shifting operations. The FPGA implement of sine and cosine functions are achieved through CORDIC Algorithm in the paper, and the input and output data of the entire structure complies with IEEE754 standards. The basic theory of CORDIC Algorithm is introduced first in the paper, then the hardware iterative formula and the flow chart get out of basic formulas are given, and the structure of the design is introduced in detail, at last synthesis and simulation results are given.

Concentrations and distributions of four polycyclic musks (galaxolide (HHCB), tonalide (AHTN), celestolide (ADBI) and phantolide (AHMI)) in surface water from the Songhua River were investigated. Experimental data showed that the Songhua River had been polluted to different degrees except the rivers source. Concentrations of HHCB, AHTN, ADBI and AHMI were in the ranges of 6.77-30.65, 2.19-7.97, < LOD-1.94 and < LOD-2.53 ng/L, respectively. The results indicated a low proportion of wastewater burden in this river, and the HHCB and AHTN were the major components. Risk assessments on HHCB and AHTN suggest that the current polycyclic musk levels in Songhua River represent a low potential risk to the aquatic organisms.

Occurrence and distribution of four polycyclic musks in nine sediment samples from the Songhua River were studied by using GC-MS. The concentrations of total polycyclic musks were in the range of 2.91-27.8 ng/g (dry weight, dw), while HHCB, AHTN, ADBI and AHMI were in the ranges of 1.89-16.00, 1.02-6.06, <LOD-2.72 and <LOD-3.02 ng/g (dry weight, dw), respectively. The results indicated that the Songhua River had been polluted with different degree except the river source, and the HHCB and AHTN were the dominant components in the sediments.

Considering the advantages and disadvantages of the mill screw down system now, a new type screw down system of caster is designed in this paper. Electro-hydraulic double-precision device is adopted in the synchronized screw down system.Bilateral synchronous motor is adopted first for coarse adjustment, and then use hydraulic servo cylinder to realize synchronization precision adjustment. It can adjust roll gap with double-precision, which can both achieve the purpose of rapid screw down and meet the accuracy requirements of the roll gap adjustment. Rotate both sides of screw down nuts using one hydraulic cylinder to achieve simultaneous fine-tuning of the roll gap. While coarse and fine adjustment, the actions are coordinate and non-interference. The screw down nut designed is compound nut, which can effectively compensate for the loosening and improve the accuracy of the roll gap adjustment. By analyzing and comparing, the new type screw down system of caster has some advantages such as double-precision adjustment, well synchronization, easy to operate and low cost, which have practical significance to improve the performance of the twin-roll casting machine.

Objective:To determine the extent to which insomnia poses an independent burden on individual function and healthcare use in Australia.

Semisolid A356 alloy feedstock was generated by reversed cone channel pouring. The influence of pouring temperatures and the reversed cone angle on the semisolid microstructure were investigated, and the microstructure of the slurry after soaking was also studied. The results indicate that the suitable pouring temperature for obtaining semisolid feedstock is not above 660℃ and the semisolid microstructure can be improved by increasing the reversed cone angle, but proper reversed cone angle should be considered for avoiding solid shell in the condition of big reversed cone angle.

As one of the most advanced technology, twin-roll strip casting technology has a huge advantage compared to conventional casting technology in iron and steel industry. In recent years, therefore, metallurgical workers are favour of the twin-roll strip casting technology and invest a great deal of reseach funding. It has achieved considerable progress. In abroad, there were several advanced iron and steel enterprises which had realized the commercialization of small-scale production. But there is still a long way to go for the mass of industrial production. Because of the very short service life of side dam, side sealing technology is one of the bottlenecks. Based on this, the paper analyzes the reason caused the very short service life of traditional side dam and improves the service life through improving heating mode. That is digging appropriate size of slot on the back of the side dam in the contact with casting roller to install resistance wire for on-line heating. The result indicate that the improved heating mode can make the temperature distribution and stress distribution of the side dam more uniform, decrease temperature gradient and thermal stress and improve stress concentration. It can improve the service life of the side dam in a certain extent.

Basic point of manifold research method for rolling theory is discussed. These methods are engineering numeration, the method of slip line network, the limit analytical method, the plastic finite element method, energy method, research rolling theory with viscosity hydrokinetics, the boundary element method, the finite twig element method and the artificial neural network technic. Point out holding crux part on the whole bog of tricks. Apply range of apiece research method are analyzed and compared. The selection to embark research methods of rolling theory is to have definite referential action.

Tension reducing is one of the important processes in the production of steel tube, especially for the production of small diameter and thin-walled tube. Tension reducing mill has wide work speed range. A series of finished tube with different diameters and wall thickness were produced from a pierced billet by changing the velocity ratio between the rack. It is important to obtain the relationship of the wall thickness variation and tension for the production of satisfied steel tube. A speed calculation model was established for a suitable tension. The setting of the initial velocity field has great effects on the convergence of iteration process or iterations, so it must strictly satisfy the velocity boundary conditions, and must not break continuity condition and approximately meet the constancy of volume.

The mechanism of the cycloaddition reaction of forming a silicic bis-heterocyclic compound between singlet dimethylmethylenesilylene (Me2C=Si:) and ethene has been investigated with the CCSD(T)//MP2/6-31G* method. From the potential energy profile, it can be predicted that, this reaction has one dominant channel. The presented rule of this dominant channel: the 3p unoccupied orbital of Si in dimethylmethylenesilylene and the p orbital of ethene forming the p-p donor-acceptor bond, resulting in the formation of three-membered ring intermediate (INT1); INT1 then isomerizes to a four-membered ring silylene (P2), which is driven by ring-enlargement effect; due to sp3 hybridization of Si atom in P2, P2 further combines with ethene to form a silicic bis-heterocyclic compound.

It is necessarily to study a new wire of economic section for market of building materials and development of social progress. Based on hardware to requirement of software, this paper exploits a computer simulation system for special straightening and shearing of wire, it face to the engineering directly. The software adopts the structure systems, which includes structure type, modularity, and expert system ability. The algorithm of the system is reliable. Its function is complete. Interface is friendly. It can be widely used in practical engineering.

Bar straightening is an important work before the bar is applied as qualified products. In this paper, the mechanics of the straightening process is analyzed in detail on the base of conjugate quadric theory. A simulation program is developed with the investigation of straightening process as well. The equations, which describe roll contour curve and the longitudinal section, are given and simulated in computer. And a brief method of designing and drawing the straightening roll contour curve is introduced.

C33H27lrN2O6, Triclinic, P-1, a= 7.4840(11) Å, b= 11.7312(17) Å, c= 17.438(2) Å, V= 1427.0(3) Å3, Z= 2, Rgt(F)= 0.0280, wRref(F2)= 0.0677, T= 293(2) K.

Laboratory feeding experiments with the poplar aphid, Chaitophorus populeti(Panzer), feeding on transgenic poplar (P. alba × P. glandulosa) varieties C13-5 and C013-5, were carried out to study the effect of transgenic poplar on the ladybird Harmonia axyridis(Pallas). The mortality and development time of the immature stages, the eclosion rate and body mass of H. axyridiswere measured. The results indicated that C. populetifeeding on different varieties of transgenic plants had no statistically significant effect on the mortality of H. axyridislarvae. The development time of larval and pupal stages were not significantly different between the two transgenic poplars and a non-transgenic poplar. Furthermore, the body mass and eclosion rate did not show any difference between the H. axyridisfeeding on aphids reared on transgenic plants and those from non-transgenic plants. It is suggested that transgenic plants have no deleterious effect on the predatory ladybird.Laboratory feeding experiments with the poplar aphid, Chaitophorus populeti(Panzer), feeding on transgenic poplar (P. alba × P. glandulosa) varieties C13-5 and C013-5, were carried out to study the effect of transgenic poplar on the ladybird Harmonia axyridis(Pallas). The mortality and development time of the immature stages, the eclosion rate and body mass of H. axyridiswere measured. The results indicated that C. populetifeeding on different varieties of transgenic plants had no statistically significant effect on the mortality of H. axyridislarvae. The development time of larval and pupal stages were not significantly different between the two transgenic poplars and a non-transgenic poplar. Furthermore, the body mass and eclosion rate did not show any difference between the H. axyridisfeeding on aphids reared on transgenic plants and those from non-transgenic plants. It is suggested that transgenic plants have no deleterious effect on the predatory ladybird.

According to the theories for stretch reducing process and steel tube plastic deformation, the energy method was used to mesh the rolled deformation zone of the steel tube into the upper limit elements, and an admissible velocity field was constructed to deduce a series of formulas of the inner virtual power consumption of deformed bodies. The rolling force during the stretch reducing process could be obtained by optimizing the upper limit power, which could provide guidelines for a proper choice of the stretch reducing process and devices for steel tube companies, as well as new products and devices.

According to the N-S equation in fluid mechanics, it is analyzed the rheological properties of strip cast-rolling deforment area with flow function method. The research problem can be simplified into 2-D when the wide of cast-rolling strip are greater than thickness. But, it still difficult to find solution for established two-dimensional partial differential equation directly. A mathematics model of velocity field in the cast-rolling area has been built by flow function method. The model not only satisfies the continues equation, the condition of no-compression and velocity boundary, but it also make the most possible to solute partial differential equation. So, in the future continue research, it has created possible conditions for saluting the mathematics model of average unit compression stress distribution in the cast-rolling deforment area.

According to the deformation characteristics of three-roll tube rolling, the existent disadvantages of traditional A Geleiyi and A Tselikov’s formulas were objectively analyzed. An assumption approximate to actual situation was put forward. After suitable simplification, the energy method was adopted to establish velocity fields for permissive movement in deformed areas, and the calculation formula of average unit pressure for three-roll tube rolling was deduced. The values of theoretical calculation are basically consistent with the measured values of large-scale aluminum tube during on-site rolling process. The results proved that the formula is reasonable.