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Offshore oil and gas development plays an important part in the global energy sector. Offshore platforms and flexible pipes are the key equipments in the whole offshore oil and gas development system. Because of the randomness and uncertainty of wave and current loads in the ocean environment, the structural design and mechanical analysis of the marine equipment can be highly complicated. Therefore, this paper reviews the recent works of the theoretical model, numerical simulation, and experimental test in three research areas: hydrodynamic analysis of offshore platforms, structural mechanics analysis of flexible pipe and cable, and monitoring technology of offshore floating structures under marine loads. By analyzing their main research methods and key technical difficulties, this paper provides theoretical basis and technical support for the reliability engineering application of offshore platforms and flexible pipelines. Also, China is relatively backward in the design of marine floating platform, the design, analysis and testing of flexible pipeline and cable, as well as the marine equipment prototype monitoring technology research. Calling for breakthroughs at the earliest possible stage in the above fields, prime research should be focused on and strategic planning should be made to deal with “key areas and stranglehold problems”. It is of great significance for the development of China’s deep-sea energy and resource development of independent technology and on time to achieve the “carbon peak” national strategic objectives.

A novel analysis is performed, incorporating time-of-flight (TOF) information to study the interactions of dark matter (DM) with standard model particles. After supernova (SN) explosions, DM with mass $m_\chi\lesssim\mathcal{O}({\rm MeV})$ in the halo can be boosted by SN neutrinos (SN$\nu$) to relativistic speed. The SN$\nu$ boosted DM (BDM) arrives on Earth with TOF which depends only on $m_\chi$ and is independent of the cross section. These BDMs can interact with detector targets in low-background experiments and manifest as afterglow events after the arrival of SN$\nu$. The characteristic TOF spectra of the BDM events can lead to large background suppression and unique determination of $m_\chi$. New cross section constraints on $\sqrt{\sigma_{\chi e} \sigma_{\chi\nu}}$ are derived from SN1987a in the Large Magellanic Cloud with data from the Kamiokande and Super-Kamiokande experiments. Potential sensitivities for the next galactic SN with Hyper-Kamiokande are projected. This analysis extends the existing bounds on $\sqrt{\sigma_{\chi e}\sigma_{\chi \nu}}$ over a broad range of $r_\chi=\sigma_{\chi \nu}/\sigma_{\chi e}$. In particular, the improvement is by 1-3 orders of magnitude for $m_\chi, Comment: PRL accepted, matched published version

Chronic low back pain patients have been observed to show a reduced shift of thorax-pelvis relative phase towards out-of-phase movement with increasing speed compared to healthy controls. Here, we review the literature on this phase shift in patients with low back pain and we analyze the results presented in literature in view of the theoretical motivations to assess this phenomenon. Initially, based on the dynamical systems approach to movement coordination, the shift in thorax-pelvis relative phase with speed was studied as a self-organizing transition. However, the phase shift is gradual, which does not match a self-organizing transition. Subsequent emphasis in the literature therefore shifted to a motivation based on biomechanics. The change in relative phase with low back pain was specifically linked to expected changes in trunk stiffness due to ‘guarded behavior’. We found that thorax-pelvis relative phase is affected by several interacting factors, including active drive of thorax rotation through trunk muscle activity, stride frequency and the magnitude of pelvis rotations. Large pelvis rotations and high stride frequency observed in low back pain patients may contribute to the difference between patients and controls. This makes thorax-pelvis relative phase a poor proxy of trunk stiffness. In conclusion, thorax-pelvis relative phase cannot be considered as a collective variable reflecting the orderly behaviour of a complex underlying system, nor is it a marker of specific changes in trunk biomechanics. The fact that it is affected by multiple factors may explain the considerable between-subject variance of this measure in low back pain patients and healthy controls alike.

The acoustic streaming which can facilitate the heat and mass transfer inside liquids is of great importance in ultrasonic processing. Most of previous investigations were mainly focused on the acoustic streaming induced by one dimensional (1D) ultrasound. In this paper, the flow field generated by 1D, 2D and 3D ultrasounds in a cubic box filled with water was investigated by numerical simulations. It is found that the jet flow emitted from the sound source is in the form of cylinder, vortex and wave, for 1D, 2D and 3D ultrasounds, respectively. When the ultrasonic dimension is increased, the flow becomes much stronger in the vicinity of the sound source but little weaker at the box center. By comparing the patterns of the flow generated by the ultrasounds of different dimensions, we demonstrate that 3D ultrasounds not only enhance the overall flow strength, but also effectively promote the uniformity of the flow and enlarge the size of vortices.

The effect of power ultrasound on the liquid phase separation of ternary Cu-32%Sn-20%Bi immiscible alloy is experimentally investigated, which shows that as compared with the layered structure formed under static condition, the macrosegregation resulted from liquid phase separation is remarkably reduced with the increase of ultrasonic amplitude. A homogenous microstructure characterized by refined (Bi) particles dispersing uniformly on the (Cu3Sn) matrix is obtained when the ultrasonic amplitude reaches the highest value of 24 μm. This is mainly ascribed to the ultrasonically induced cavitation and acoustic streaming, which promotes the nucleation, the fragmentation, and the dispersion of (Bi) droplets. The finally solidified immiscible alloy exhibits obvious improvements in electrochemical corrosion resistance, microhardness and wear-resisting if compared with those in static solidification. These results prove that applying power ultrasound is an effective way to modulate the liquid phase separation and enhance the applied performance for immiscible alloys.

Introduction: Pelvic Girdle Pain (PGP) is an important clinical problem that deserves more attention. Several treatment regimens have been presented that appear to be somewhat promising, but it was reported that about 10% of patients still suffer from the problems 11 years after their inception. This situation should be improved. Purpose: We present a personalized history, with first the acceptance of the concept of ‘PGP’, around 2005, and then continued problems in really understanding PGP's nature and causes. We propose to engage in ‘deconstruction’ of PGP, that is, disentangling the large variety of processes involved. Implications: Deconstructing PGP is a venture into the unknown. Still, science should proceed on the basis of what we know already. To understand PGP, experts emphasize the importance of biomechanics or of psychology, and we propose to insert ‘inflammation’ between these two levels of understanding, that is to say, the full development from low grade local inflammation to systemic inflammation and neuroinflammation. Inflammation is bidirectionally related to biomechanical as well as psychological processes. For clinicians, challenging our “beliefs and understanding of PGP, rather than being ‘stuck’ with a preferred modus operandi” has major practical implications. It requires continuous monitoring of the patient, and a willingness to change direction. More scientific disciplines are relevant to understanding, and treating, PGP than a single human being can master. Creative flexibility of clinicians would be a promising starting point to improve overall treatment effects in PGP.

Ultrasonic melt treatment is an environmentally friendly and no-polluting external field technology and has great application potential in materials fabrication. Power ultrasound with different intensities was introduced into the liquid phase separation and solidification process of ternary Al-45%Sn-5%Si immiscible alloy to explore the effects of ultrasound on the formation of macro- and microstructure. It was found that the previously apparent macrosegregation caused by the large density difference between immiscible liquid (Al) and (Sn) phases was gradually reduced and even suppressed with the increase of ultrasonic amplitude. Meanwhile, the ultrasonic waves also significantly modified monotectic structures, within which (Al) phase transformed from coarse dendrites to refined equiaxed grains, and (Si) phase evolved from long strips to small blocks. The introduction of ultrasound weakened the texture of solidified structure, whereas the growth orientation relationship between monotectic (Al) and (Si) phases remained unchanged. The theoretical analysis and calculation results indicated that ultrasonic cavitation and acoustic streaming were the dominant effects to modulate the macro- and microstructural evolution. This would improve the exploiting and utilization of immiscible alloys by ultrasonic processing technology.

Objective: To investigate the effect of oxycodone hydrochloride injection preemptive analgesia on serum inflammatory factors, neurotransmitter index and immune function in patients with laparoscopic cholecystectomy. Methods: According to random data table, 113 patients undergoing laparoscopic cholecystectomy were divided into control group (n=57) and observation group (n=56), patients in the control group were treated with sufentanil citrate injection analgesia, and the observation group patients were given oxycodone hydrochloride injection analgesia, level of serum inflammatory factors [tumor necrosis factor-α (TNF-α), interleukin-6 (IL-6)], neurotransmitter index [5-hydroxy tryptamine (5-HT), P substance] and immune function index [CD4+ , CD8+ , CD4+ /CD8+ ] of two groups between preoperative and postoperative 1d were compared. Results: There were no significant difference in level of TNF-α, IL-6, 5-HT, P substance, CD4+ , CD8+ and CD4+ /CD8+ between the two groups preoperative. Compared with the level of the same group preoperative, at postoperative 1 d level of TNF-α, IL-6, 5-HT, P substance, CD8+ were significantly increased, moreover level in the observation group were significantly lower compared with the control group, the difference was statistically significant; Postoperative 1 d, level of CD4+ , CD4+ /CD8+ in the two groups were significantly lower than the preoperative level within the group, and the observation group was significantly higher than the control group. Conclusion: Oxycodone hydrochloride injection preemptive analgesia in laparoscopic cholecystectomy can effectively reduce serum inflammatory factors and neurotransmitter index release, improve immune function, has an important clinical value.

The offshore floating platform shows the strong nonlinear characteristics subject to harsh ocean environmental conditions. It is of practical significance and engineering value to predict the marine environmental load and platform motion response by using the prototype monitoring information. Meanwhile, under the interaction of the high-frequency six degrees of freedom (DOF) movements of the platform. Based on the long-term prototype monitoring data of a semi-submersible platform in the South China Sea, the present paper mainly studies the following two aspects: 1.The prediction of ocean environmental load considering time correlation is studied based on the method of long-short-term memory (LSTM) neural network with the combination of the field monitoring data. The comparison between predicted and measured results shows that the present prediction method has the high accuracy and low computation cost. Besides, this method can be extended to short-term predictions of other environmental loads. 2.The nonlinear mapping relationship between the ocean environment load and the floater motions is constructed based on the deep learning method. The simulated results indicated that the mapping relationship can be used to predict the six DOFs motions of the platform with high accuracy by using the forecasting prototype monitoring data and ocean weather information. Based on this research and the short-term prediction of environmental loads, we can do some studies on short-term prediction of floater motions in the future.

A crosstalk between multiple biological pathways has been proposed in biological processes. However, the existence and degree of this phenomenon in patients with preeclampsia (PE) have not been strictly investigated. Thus, this study explored an dysregulated pathway set (DPS) for PE based on pathway crosstalk network (PCN) related analysis. In the present study, four steps were performed in the inference of DPS: acquiring data of gene expression, pathway and protein-protein interaction (PPI) construction; building a PCN through integrating the information in these datasets and Pearson's correlation coefficient (PCC). A principal component analysis (PCA) approach was used to compute the activity of every pathway for selecting seed pathway of PCN. DPS was evaluated by measuring of an area under the receiver operating characteristics curve (AUC) and seed pathway from PCN. Consequently, a total of 420 pathways and 6,032 crosstalks were mapped to the PCN, in which RIG-I/MDA5-mediated induction of IFN-α/β pathways was identified as the seed pathway that had the greatest changes in activity scores across PE patients and normal controls. DPS was composed of 15 dysregulated pathways and 46 crosstalks, in which CLEC7A (Dectin-1) signaling possessed the highest degree of 12, which indicated it exerted an important role in the DPS. Our results revealed crosstalk between pathways and the DPS crucial for PE pathogenesis, which aid in excavating potential biomarkers of PE therapy and unveil the underlying pathological mechanism of this disease.

BackgroundHip abductor weakness and unilateral pain in patients with moderate hip osteoarthritis may induce changes in frontal plane kinematics during walking that could affect stability and fall risk.MethodsIn 12 fall-prone patients with moderate hip osteoarthritis, 12 healthy peers, and 12 young controls, we assessed the number of falls in the preceding year, hip abductor strength, fear of falling, Harris Hip Score, and pain. Subjects walked on a treadmill with increasing speeds, and kinematics were measured opto-electronically. Parameters reflecting gait stability and regressions of frontal plane center of mass movements on foot placement were calculated. We analyzed the effects of, and interactions with group, and regression of all variables on number of falls.FindingsPatients walked with quicker and wider steps, stood shorter on their affected leg, and had larger peak speeds of frontal plane movements of the center of mass, especially toward their unaffected side. Patients' static margins of stability were larger, but the unaffected dynamic margin of stability was similar between groups. Frontal plane position and acceleration of the center of mass predicted subsequent step width. The peak speed of frontal plane movements toward unaffected had 55% common variance with number of falls, and adding the Harris Hip Score into bivariate regression led to 83% “explained” variance.InterpretationQuickening and widening steps probably increase stability. Shorter affected side stance time to avoid pain, and/or weakened affected side hip abductors, may lead to faster frontal plane trunk movements toward the unaffected side, which could contribute to fall risk.

C26H19Cl8KN2NdO13.5, triclinic, P1̅ (no. 2), a = 8.6114(17) Å, b = 12.665(3) Å, c = 16.997(3) Å, α = 96.53(3)°, β = 103.28(3)°, γ = 97.89(3)°, V = 1766.6(6) Å3, Z = 2, R gt (F) = 0.0254, wR ref (F 2 ) = 0.0838, T = 293 K.

Transverse plane pelvis rotations during walking may be regarded as the "first determinant of gait". This would assume that pelvis rotations increase step length, and thereby reduce the vertical movements of the centre of mass-"the pelvic step". We analysed the pelvic step using 20 healthy young male subjects, walking on a treadmill at 1-5. km/h, with normal or big steps. Step length, pelvis rotation amplitude, leg-pelvis relative phase, and the contribution of pelvis rotation to step length were calculated. When speed increased in normal walking, pelvis rotation changed from more out-of-phase to in-phase with the upper leg. Consequently, the contribution of pelvis rotation to step length was negative at lower speeds, switching to positive at 3. km/h. With big steps, leg and pelvis were more in-phase, and the contribution of pelvis rotation to step length was always positive, and relatively large. Still, the overall contribution of pelvis rotations to step length was small, less than 3%. Regression analysis revealed that leg-pelvis relative phase predicted about 60% of the variance of this contribution. The results of the present study suggest that, during normal slow walking, pelvis rotations increase, rather than decrease, the vertical movements of the centre of mass. With large steps, this does not happen, because leg and pelvis are in-phase at all speeds. Finally, it has been suggested that patients with hip flexion limitation may use larger pelvis rotations to increase step length. This, however, may only work as long as the pelvis rotates in-phase with the leg. © 2013 Elsevier B.V.

_Dear Editor of Clinical Biomechanics,_ We read with interest Kibsgard et al.'s above Clinical Biomechanics paper. Radiostereometric Analysis was performed to measure sacroiliac movements during the Active Straight Leg Raise (ASLR) in 12 patients with chronic Pelvic Girdle Pain (PGP). Of the patients, 8 had been diagnosed with bilateral, and 4 with unilateral sacroiliac pain. All were about to undergo sacroiliac fusion surgery. We fully agree with Kibsgard et al. that this is an important field. About 5% of all pregnant women suffer from PGP that is sufficiently serious to warrant medical attention (Wu et al., 2004). Also athletes with groin pain may have PGP (Verrall et al., 2001), often in the form of osteitis pubis. Both groups of patients have difficulties performing the ASLR (Mens et al., 2006). Contralateral to the side of the raising leg, Kibsgard et al. observed 0.8° backward rotation of the ilium with respect to the sacrum (range−0.3° to −1.3°, ‘minus’ for backward), and ipsilaterally on average 0.0° (range −1.0° to +0.5°). We congratulate Kibsgard et al. with this contribution to the field. Still, there are some questions.

The oscillation and migration of bubbles within an intensive ultrasonic field are important issues concerning acoustic cavitation in liquids. We establish a selection map of bubble oscillation mode related to initial bubble radius and driving sound pressure under 20 kHz ultrasound and analyze the individual-bubble migration induced by the combined effects of pressure gradient and acoustic streaming. Our results indicate that the pressure threshold of stable and transient cavitation decreases with the increasing initial bubble radius. At the pressure antinode, the Bjerknes force dominates the bubble migration, resulting in the large bubbles gathering toward antinode center, whereas small bubbles escape from antinode. By contrast, at the pressure node, the bubble migration is primarily controlled by acoustic streaming, which effectively weakens the bubble adhesion on the container walls, thereby enhancing the cavitation effect in the whole liquid.

In order to facilitate the advanced measurement system with real-time interaction in smart grid and to satisfy the requirements for power quality management, a wireless ad hoc smart metering system for power quality using Internet of things (IoTs) technology is presented in the paper. By utilizing the energy metering module to collect energy information, the ZigBee ad hoc networks to transmit energy information, and the user monitoring terminal to support power grids management, the proposed system is able to efficiently realize the power quality information collection, transmission, processing and sharing. Experimental results demonstrate that the system performs real-time and precious monitoring of the distributed client power quality information, together with friendly and intelligent interaction capability.

After stacking pre-oxidation treatment, lead anode slime was leached in sulfuric acid added with sodium chloride and oxidant of sodium chlorate. The leaching rates of As, Te, Sb, Bi and Cu are more than 98% with potential controlled at 500mV. And noble metals are left in the residue, which are separated from the base metals effectively. Through cooling and crystallizing out arsenate, the solution is reduced with potential controlled. According to reducing slag, the recovery rate of Te is 96.52%. Sb is recovered by neutralizing hydrolysis and the recovery rate is 95.2%. By the effect of iron powder, As, Bi and Cu are entirely reduced with the recovery rates of Bi and Cu to be 91.56% and 83.49%, respectively. The total recovery of As from the crystalline product and reducing slag achieves 91.56%.

Background. To explore influence of continuous illumination, luzindole, and Tamoxifen on incidence of scoliosis model of rats.Methods. Thirty-two one-month-old female rats were rendered into bipedal rats. The bipedal rats were divided into 4 groups: group A by intraperitoneal injection of luzindole and continuous illumination; group B by intraperitoneal injection of luzindole only; group C by intraperitoneal injection of luzindole and oral administration of Tamoxifen; and group D by intraperitoneal injection of equivalent saline. Radiographs were taken at 8th week and 16th week, and incidence and the Cobb angles of scoliosis were calculated. At 16th week, all rats were sacrificed. Before the sacrifice, the levels of calmodulin were measured in each group.Results. At 8th week, scoliosis occurred in groups A and B, with an incidence of 75% and 12.5%, respectively, while rats in group C or D had no scoliosis. At 16th week, scoliosis incidences in groups A and B were 57% and 62.5%, respectively. No scoliosis occurred in group C or D. Calmodulin in platelets in group B was significantly different, compared with groups A and D. There was no significant difference in calmodulin in platelets in groups B and C.Conclusion. By intraperitoneal injection of luzindole in bipedal rats, scoliosis rat models could be successfully made. Under light, incidence of scoliosis may be increased at an early period but it is reversible. Tamoxifen can suppress natural process of scoliosis.

To deal with the problem that dead time is indispensable and that its compensation is difficult to implement especially when taking Space Vector Modulation method to modulate the inverter stage of Two-Stage Matrix Converter (TSMC), this paper presents a Carrier-based Modulation (CBM) strategy suitable for the TSMC and amplifies concerned the uniqueness of the proposed CBM. Based on this, the dead-time effect to TSMC is analyzed, formula for describing dead-time effect is induced, and two compensation methods are given, namely modulation voltage modification method and time compensation method. At last, the uncompensated and compensated experiments are carried out on the prototype, and the results prove that this strategy meets the satisfaction.

The AZ31 magnesium alloy flow stresses have been investigated in the strain rates of 0.03~3s-1and temperature range of 300~400°C. The result showed that dynamic recovery and dynamic recrystallization occurred obviously during the hot compression of AZ31 magnesium alloy. In order to represent the flow stress of plastic deformation accurately, the constitutive equation was built by using the dynamic recovery model and dynamic recrystallization model, and its parameters of the constitutive equation were determined by multivariate nonlinear regression analysis. The two-step constitutive equation not only expressed the variation of flow stress with strain rate, deformation temperature and strain, but also revealed the characteristic of dynamic recrystallization kinetics of AZ31 magnesium alloy. Its accuracy was higher than the flow stress of hyperbolic sine model, and the maximum relative errors of two constitutive equation models calculation values compared with experiment data were 5% and 6.5% respectively.

Psoas function is a topic of considerable relevance in sports and clinical science. However, the literature on psoas function is not sufficiently consistent. Questions are, amongst others, if during hip flexion the psoas always has the same function as the iliacus, and if the psoas affects the hip more than the lumbar spine. In the present study, 17 healthy women, 20-40 years, performed the active straight leg raise (ASLR), with the right or the left leg ("Side"), and without or with weight added above the ankle ("Condition"). Electromyographic (EMG) activity of psoas and iliacus were recorded with fine-wire electrodes, and of rectus femoris and adductor longus with surface electrodes, all on the right side. Movements of the leg were recorded with active markers and a camera system. During ASLR, the iliacus, rectus femoris, adductor longus and psoas were active ipsilaterally, but psoas was also active contralaterally. All muscles started to contract before movement onset, the iliacus, rectus femoris, and adductor longus largely at the same time, before the psoas. There was no significant difference between the amplitude or time of onset of ipsilateral and contralateral psoas EMG activity, nor was there a significant interaction between Side and Condition for the psoas. Although ipsilateral psoas activity is consistent with the psoas being a hip flexor, contralateral activity is not. The most simplest explanation of the pattern found is that the psoas is bilaterally recruited to stabilize the lumbar spine, probably in the frontal plane. © 2010 The Author(s).

A simple method to prepare multi-walled carbon nanotubes (MWCNTs) with high purity, high-aspect ratio and especially minimal defects is presented by low-power ultrasonic-assisted treatment of raw carbon nanotubes in hot concentrated hydrochloric acid under continuous reflux conditions. The evolution of surface morphology of MWCNTs during the treatment is evaluated by transmission electron microscopy, and microstructure is characterised by Fourier transform infrared and micro-Raman spectroscopy. The results show that with increasing the treatment time, the external layers with defects are peeled off piece by piece from the surface of MWCNTs until the inner graphite layers with good chemical resistance are exposed. The MWCNTs treated for less than 15 h by this method have been demonstrated to have minimal microstructural defects and large aspect ratios as compared to those treated in mixed concentrated nitric acid and sulphuric acid, which is further confirmed that almost no manganese dioxide particles can ...

Women with pregnancy-related pelvic girdle pain (PPP), or athletes with groin pain, may have trouble with the active straight leg raise (ASLR), for which a pelvic belt can be beneficial. How the problems emerge, or how the belt works, remains insufficiently understood. We assessed muscle activity during ASLR, and how it changes with a pelvic belt. Healthy nulligravidae (N=17) performed the ASLR, and walked on a treadmill at increasing speeds, without and with a belt. Fine-wire electromyography (EMG) was used to record activity of the mm. psoas, iliacus and transversus abdominis, while other hip and trunk muscles were recorded with surface EMG. In ASLR, all muscles were active. In both tasks, transverse and oblique abdominal muscles were less active with the belt. In ASLR, there was more activity of the contralateral m. biceps femoris, and in treadmill walking of the m. gluteus maximus in conditions with a belt. For our interpretation, we take our starting point in the fact that hip flexors exert a forward rotating torque on the ilium. Apparently, the abdominal wall was active to prevent such forward rotation. If transverse and oblique abdominal muscles press the ilia against the sacrum (Snijders' "force closure"), the pelvis may move as one unit in the sagittal plane, and also contralateral hip extensor activity will stabilize the ipsilateral ilium. The fact that transverse and oblique abdominal muscles were less active in conditions with a pelvic belt suggests that the belt provides such "force closure", thus confirming Snijders' theory. © 2009 Elsevier Ltd. All rights reserved.

In speeding-up normal walking, relative phase between horizontal thorax and pelvis rotations changes from more in-phase (synchronous) to more out-of-phase. In pathology (stroke, Parkinson's disease, low-back pain, pregnancy-related pelvic girdle pain), this often fails to happen. Even in healthy gait, however, these phenomena remain poorly understood. Thorax-pelvis relative phase may increase with either stride length, or stride frequency. Sixteen healthy male subjects walked on a treadmill at 0.5. m/s, 1.0. m/s, or 1.5. m/s, with small, normal, or large steps. Increasing stride length (with lower frequency) led to larger spinal rotations, larger thorax-pelvis relative phase, and lower pelvis-leg relative phase, while the thorax continued to counterrotate with respect to the leg. With small steps, speeding-up hardly affected thorax-pelvis relative phase, and spinal amplitudes remained low. From a certain walking speed onwards, pelvis rotations start to contribute to stride length, and thus to speed (the " pelvic step" ). This phenomenon appears to be driven, and the present study suggests, at least for higher speeds, that also thoracic counterrotations are driven, and not determined by the passive dynamics of the system. For patients, several strategies may exist to avoid large thorax-pelvis relative phase, and the concomitant large rotations of the spine: walking slowly, walking with small steps, adapting the timing of thorax rotations to that of the pelvis, or refraining from adapting the timing of pelvis rotations to the movements of the leg. © 2010 Elsevier B.V.

The effective site-selective interaction between the π-bonds in the aromatic rings of the polyaniline and the graphitic structure of multiwall carbon nanotubes would strongly facilitate the charge-transfer reaction between the two components. We adopted multiwall carbon nanotubes (MWNTs) with minimal defects as templates and facilely fabricated carbon nanotube−polyaniline nanocomposites with uniform core−shell structures by ultrasonic assisted in situ polymerization. By varying the ratio of aniline monomers and carbon nanotubes, the thickness of polyaniline layers can be effectively controlled. The results indicated that the presence of carbon nanotubes with minimized defects induced the formation of a more planar conformation of polyaniline even when a high weight percent of aniline was loaded. As a result, macroscopically, great improvements in the electrical and electrochemical properties of the resulting nanocomposites were observed.

Poly(3-hydroxybutyrate- co -3-hydroxyvalerate) (PHBV) has attracted the attention of academia and industry because of its biodegradability, biocompatibility, thermoplasticity and plastic-like properties. However, PHBV is unstable above 160 °C during melt processing at a temperature above the melting temperature, which restricts practical applications as a commodity material. It is widely believed that thermal degradation of PHBV occurs almost exclusively via a random chain scission mechanism involving a six-membered ring transition state. Here, 2,2′-bis(2-oxazoline) (BOX) was selected to modify PHBV to control the formation of six-membered ring ester during thermal degradation. The resulting hydroxyl-terminated PHBVs (HT-PHBVs) had improved thermal stability due to a decrease in the negative inductive effect of the neighboring group of methylene groups at the β-position to the ester oxygen, and a decrease in the electron-denoting effect of substituent group of carbon atoms at α-position to the ester oxygen. The optimal reaction temperature and time were determined to be 95 °C and 6 h, respectively. Compared with those of original PHBV, the temperature determined at 5% weight loss ( T 5% ), the initial decomposition temperature ( T 0 ), the maximum decomposition temperature ( T max ), the complete decomposition temperature ( T f ) of HT-PHBV prepared under the optimal conditions increased by 31, 24, 19 and 19.1 °C, respectively.

Walking is impaired in Pregnancy-related Pelvic girdle Pain (PPP). Walking velocity is reduced, and in postpartum PPP relative phase between horizontal pelvis and thorax rotations was found to be lower at higher velocities, and rotational amplitudes tended to be larger. While attempting to confirm these findings for PPP during pregnancy, we wanted to identify underlying mechanisms. We compared gait kinematics of 12 healthy pregnant women and 12 pregnant women with PPP, focusing on the amplitudes of transverse segmental rotations, the timing and relative phase of these rotations, and the amplitude of spinal rotations. In PPP during pregnancy walking velocity was lower than in controls, and negatively correlated with fear of movement. While patients' rotational amplitudes were larger, with large inter-individual differences, spinal rotations did not differ between groups. In the patients, peak thorax rotation occurred earlier in the stride cycle at higher velocities, and relative phase was lower. The earlier results on postpartum PPP were confirmed for PPP during pregnancy. Spinal rotations remained unaffected, while at higher velocities the peak of thorax rotations occurred earlier in the stride cycle. The latter change may serve to avoid excessive spine rotations caused by the larger segmental rotations. © 2008 The Author(s).

Microstructures and mechanical properties of Mg-2.0%Ce-0.7%Zn-0.7%Zr alloy were studied. The results of scanning electron microscopy show that Mg12Ce phase mainly distributes at the grain boundaries. The fine Mg12Ce phase can apparently elevate recrystallization temperature by preventing the grain boundary migration. No dynamic recrystallization occurs during the hot-extrusion. The mechanical properties of as extruded specimens are σ b=278.5 MPa, δ=12.0%, while those of the specimens annealed at 250 °C for 100 h are σ b=272.6 MPa, δ=11.3%, which indicate that the alloy has good mechanical properties at room temperature.

Objective. To examine the effects of pregnancy on the coordination of transverse pelvic and thoracic rotations during gait. Design. Gait of healthy pregnant women and nulligravidae was studied during treadmill walking at predetermined velocities ranging from 0.17 to 1.72 m/s. Background. Pelvis–thorax coordination during walking is altered in women with postpartum pregnancy-related pelvic girdle pain. This coordination has not been investigated in a healthy pregnant population. Methods. Comfortable walking velocity was established. Amplitudes of pelvic and thoracic rotations were calculated. Their coordination was characterized by relative Fourier phase and its standard deviation. Results. Comfortable walking velocity was significantly reduced. The amplitudes of pelvic and thoracic rotations were somewhat reduced, with significantly smaller intra-individual standard deviations. Also pelvis–thorax relative Fourier phase was somewhat smaller, its intra-individual standard deviation was negatively correlated with week of pregnancy, and significantly lower at velocities P 1.06 m/s. Conclusions. The general pattern of gait kinematics in pregnant women is very similar to that of nulligravidae. Still, it appears that pregnant women experience difficulties in realizing the more anti-phase pelvis–thorax coordination that is required at higher walking velocities. Relevance The present study shows that gait in healthy pregnancy is remarkably normal, but some differences in pelvis–thorax coordination were detected. In healthy pregnancy, anti-phase pelvis–thorax coordination appears difficult, but less so than in pregnancy-related pelvic girdle pain. Better understanding of gait in healthy pregnancy may provide insight into the gait problems of women with pregnancy-related pelvic girdle pain. � 2004 Elsevier Ltd. All rights reserved.

Patients with non-specific low back pain, or a similar disorder, may stiffen their trunk, which probably alters their walking coordination. To study the direct effects of increasing trunk stiffness, we experimentally increased trunk stiffness during walking, and compared the results with what is known from the literature about gait coordination with, e.g., low back pain. Healthy subjects walked on a treadmill at 3 speeds (0.5, 1.0 and 1.5. m/s), in three conditions (normal, while contracting their abdominal muscles, or wearing an orthopedic brace that limits trunk motions). Kinematics of the legs, thorax and pelvis were recorded, and relative Fourier phases and amplitudes of segment motions were calculated. Increasing trunk stiffness led to a lower thorax-pelvis relative phase, with both a decrease in thorax-leg relative phase, and an increase in pelvis-leg relative phase, as well as reduced rotational amplitude of thorax relative to pelvis. While lower thorax-pelvis relative phase was also found in patients with low back pain, higher pelvis-leg relative phase has never been reported in patients with low back pain or related disorders. These results suggest that increasing trunk stiffness in healthy subjects causes short-term gait coordination changes which are different from those seen in patients with back pain. © 2013 Elsevier B.V.

Transversus abdominis (TA), obliquus internus (OI), and obliquus externus (OE) are involved in multiple functions: breathing, control of trunk orientation, and stabilization of the pelvis and spine. How these functions are coordinated has received limited attention. We studied electromyographic (EMG) activity of right-sided muscles and 3-dimensional moments during treadmill walking at six different speeds (1.4-5.4. km/h) in sixteen healthy young women. PCA revealed time series of trunk moments to be consistent across speeds and subjects though somewhat less in the sagittal plane. All three muscles were active during ≥075% of the stride cycle, indicative of a stabilizing function. Clear phasic modulations were observed, with TA more active during ipsilateral, and OE during contralateral swing, while OI activity was largely symmetrical. Fourier analysis revealed four main frequencies in muscle activity: respiration, stride frequency, step frequency, and a triphasic pattern. With increasing speed, the absolute power of all frequencies remained constant or increased; the relative power of respiration and stride-related activities decreased, while that of step-related activity and the triphasic pattern increased. Effects of speed were gradual, and EMG linear envelopes had considerable common variance (>70%) across speeds within subjects, suggesting that the same functions were performed at all speeds. Maximum cross-correlations between moments and muscle activity were 0.2-0.6, and further analyses in the time domain revealed both simultaneous and consecutive task execution. To deal with conflicting constraints, the activity of the three muscles was clearly coordinated, with co-contraction of antagonists to offset unwanted mechanical side-effects of each individual muscle. © 2011 Elsevier B.V.

The Active Straight Leg Raise (ASLR) is an important test in diagnosing pelvic girdle pain (PGP). It is difficult to understand what happens normally during the ASLR, let alone why it would be impaired in PGP. In the present study, healthy subjects performed the ASLR under normal conditions, with weight added above the ankle, and while wearing a pelvic belt. Activity of the abdominal muscles, rectus femoris (RF), and biceps femoris (BF) was recorded with surface electromyography (EMG), and transversus abdominis (TA) with fine wire EMG. RF was ipsilaterally active, BF contralaterally, and the abdominal muscles bilaterally. All muscle activity was higher with weight, and abdominal muscle activity was lower with the pelvic belt. In both these conditions, TA and obliquus abdominis internus (OI) were more asymmetrically active than obliquus externus. The abdominal muscles engage in multitasking, combining symmetric and asymmetric task components. Hip flexion causes an unwanted forward pull on the ipsilateral ilium, which is counteracted by contralateral BF activity. To transfer this contralateral force toward ipsilateral, the lateral abdominal muscles press the ilia against the sacrum (" force closure" ). Thus, problems with the ASLR may derive from problems with force closure. Also abdominal wall activity counteracts forward rotation of the ilium. Moreover, contralateral BF activity causes transverse plane rotation of the pelvis, often visible as an upward movement of the contralateral anterior superior iliac spine. Such transverse plane rotation is countered by ipsilateral TA and OI. The present study facilitates the understanding of what normally happens during the ASLR. © 2012 Elsevier Ltd.

The activities of four CYP450 enzymes (CYP3A, 1A2, 2El and 2C) and the mRNA expression levels of CYP1A2, 2El, 2Cll and 3A1 in rat liver were determined after Wistar rats were orally administered with brucine (BR) at three dosage levels (3, 15 and 60 mg.kg-1 per day) and the high dose of BR combined with glycyrrhetinic acid (GA, 25 mg.kg-1 per day) or liquiritin (LQ, 20 mg.kg-1 per day) for 7 consecutive days. Compared with the control, brucine caused 24.5% and 34.6% decrease of CYP3A-associated testosterone 6beta-hydroxylation (6betaTesto-OH) and CYP2C-associated tolbutamide hydroxylation (Tol-OH), respectively, and 146.1% increase of CYP2El-associated para-nitrophenol hydroxylation (PNP-OH) at the high dose level. On the other hand, (BR+GA) caused 51.4% and 33.5% decrease, respectively, of CYP2El-associated PNP-OH and CYP1A2-associated ethoxyresorufin-O-de-ethylation (EROD) as compared with the high dose of BR group. Meanwhile, (BR+LQ) caused 41.1% decrease of CYP2El-associated PNP-OH and 37.7% increase of CYP2C-associated Tol-OH. The results indicated that the co-administration of BR with GA or LQ had effect on mRNA expression and activities of the CYP450 enzymes mentioned above to some extent, and the in vivo antagonism of LQ on BR-induced CYPs adverse effects and the in vivo inhibitory action of GA on CYP2E1 and 1A2 might play an important role in the detoxification of Radix Glycyrrhizae against Strychnos nux-vomica L.

Patients with chronic non-specific low back pain (LBP) walk with more synchronous (in-phase) horizontal pelvis and thorax rotations than controls. Low thorax-pelvis relative phase in these patients appears to result from in-phase motion of the thorax with the legs, which was hypothesized to affect arm swing. In the present study, gait kinematics were compared between LBP patients with lumbar disc herniation and healthy controls during treadmill walking at different speeds and with different step lengths. Movements of legs, arms, and trunk were recorded. The patients walked with larger pelvis rotations than healthy controls, and with lower relative phase between pelvis and thorax horizontal rotations, specifically when taking large steps. They did so by rotating the thorax more in-phase with the pendular movements of the legs, thereby limiting the amplitudes of spine rotation. In the patients, arm swing was out-of phase with the leg, as in controls. Consequently, the phase relationship between thorax rotations and arm swing was altered in the patients. © The Author(s) 2010.

This study conducted several approaches to determine development and succession of different types of biofilms (i.e., colonization and accumulation biofilms). Changes in total metabolic activity, bacterial and algal composition within different biofilms from two river ecosystems were analyzed. They were related to water quality parameters in order to assess major factors influencing biofilm growth. Significant differences in chlorophyll a concentrations in biofilms and water between two rivers were due to differences in light intensity, water current velocity, and turbidity. Colonization of epilithic algae in biofilms mainly resulted from high levels of nutrients (up to 2.8 mgL(-1) of phosphate) and water chlorophyll a, and may be caused by attachment of planktonic algae. However, epilithic algae may also serve as the source of planktonic algae. Oxidizable substrates measured as chemical oxygen demand were found to directly increase bacterial growth or indirectly affect growth a week later. One-month colonization biofilms were the most sensitive to change of water quality, and had the greatest number of significant relationships to physico-chemical and biological parameters among three types of biofilms. This suggested that 1-month colonization biofilms were applicable for biomonitoring water quality.

This paper presents a multi-band orthogonal frequency-division multiplexing (MB-OFDM) based ultra-wideband (UWB) baseband inner transceiver. Design challenges arise from the requirements for high data rates, low power consumption, and low cost. The proposed UWB transceiver utilizes both pipelined and parallel structures to reduce the critical path and increase the system throughput. Implemented by TSMC 0.18 mum technology, the design supports 528-Msample/s throughput and 480-Mbps data rate, and consumes power less than 500 mW at 132-MHz clock rate. The whole system is designed, evaluated, and verified by the SystemC and Verilog-HDL languages through simulations. Multi-path fading, including CM1, CM2, CM3, and CM4 channel models, additive white Gaussian noise (AWGN), and up to plusmn40 ppm carrier frequency offset (CFO) and sampling frequency offset (SFO) are considered in both floating-point (FLP) and fixed-point (FXP) simulations to evaluate the system performance.

The in vivo and in vitro metabolism of jatrorrhizine has been investigated using a specific and sensitive LC/MS/MS method. In vivo samples including rat feces, urine and plasma collected separately after dosing healthy rats with jatrorrhizine (34 mg/kg) orally, along with in vitro samples prepared by incubating jatrorrhizine with rat intestinal flora and liver microsome, respectively, were purified using a C(18) solid-phase extraction cartridge. The purified samples were then separated with a reversed-phase C(18) column with methanol-formic acid aqueous solution (70:30, v/v, pH3.5) as mobile phase and detected by on-line MS/MS. The structural elucidation of the metabolites was performed by comparing their molecular weights and product ions with those of the parent drug. As a result, seven new metabolites were found in rat urine, 13 metabolites were detected in rat feces, 11 metabolites were detected in rat plasma, 17 metabolites were identified in intestinal flora incubation solution and nine metabolites were detected in liver microsome incubation solution. The main biotransformation reactions of jatrorrhizine were the hydroxylation reaction, the methylation reaction, the demethylation reaction and the dehydrogenation reaction of parent drug and its relative metabolites. All the results were reported for the first time, except for some of the metabolites in rat urine.