Prompt diagnosis and therapy of aneurysms are critical for patients with nontraumatic subarachnoid hemorrhage (SAH).The aim of our study was to assess the clinical usefulness of multislice computed tomography angiog...Prompt diagnosis and therapy of aneurysms are critical for patients with nontraumatic subarachnoid hemorrhage (SAH).The aim of our study was to assess the clinical usefulness of multislice computed tomography angiography (CTA) in the surgical and endovascular treatment of intracranial aneurysms.A total of 195 cases with 206 intracranial aneurysms underwent CTA.Fifty (24%) aneurysms underwent surgical clipping while 156 (76%) aneurysms underwent endovascular coiling.In the five missed aneurysms at digital substraction angiography and the nine aneurysms with mass intracerebral hematomas,surgical treatment was successfully performed based on 16-slice CTA alone,and the other 36 aneurysms were clipped on the main basis of the CTA.The intraoperative findings correlated well with the CTA findings and all aneurysms were clipped successfully.Sixteen-slice CTA image information has been shown to determine the choice of aneurysm therapy and assist the surgical and endovascular treatment of intracranial aneurysms.展开更多
The effects of hot-strip coiling temperature on Ti(C,N) precipitation, texture and hydrogen permeation behavior in DC06 EK enamel steel were investigated by TEM, EBSD test and electrochemical hydrogen permeation exp...The effects of hot-strip coiling temperature on Ti(C,N) precipitation, texture and hydrogen permeation behavior in DC06 EK enamel steel were investigated by TEM, EBSD test and electrochemical hydrogen permeation experiment. It was found that the Ti(C,N) particles in hot-strip coarsened with increasing coiling temperature, whereas after cold-rolling and annealing, the size difference of Ti(C,N) particles was lessened. The hot-strip coiling temperature has a significant impact on the recrystallized texture in the subsequent cold-rolled and annealed sheet. Hot-strip using high temperature(700 ℃) coiling leads to strong {111} recrystallized texture in annealed sheet, with peak intensity 9.2. On the contrary, in annealed sheets using hot-strip coiling at 650 ℃, their {111} recrystallized textures were weaker, which was also reflected in their rmvalues. Even though the hydrogen diffusion coefficient is slightly lower(7.76×10^(-5) mm^2/s) in annealed sheet using low temperature coiling(600 ℃), appropriately higher coiling temperature is more suitable for DC06 EK enamel steel combining both good drawability and fish-scale resistance.展开更多
The effect of coiling temperatures on the evolution of texture in Ti-IF steel during ferritic hot rolling, cold rolling and annealing was studied. It was found that texture evolution at high temperature coiling is abs...The effect of coiling temperatures on the evolution of texture in Ti-IF steel during ferritic hot rolling, cold rolling and annealing was studied. It was found that texture evolution at high temperature coiling is absolutely different from that at low temperature one. The hot band texture includes a strong α-fiber as well as a weak γ-fiber after ferritic hot rolling and low temperature coiling. Both of them intensify after cold rolling and a γ-fiber with peak at {111}〈112〉 is the main texture of annealed samples. However, the main component of the hot band texture after high temperature coiling is v-fiber. After cold rolling, the intensity of γ texture reduces; α fiber (except {111}〈110〉 component) intensifies and a strong and well-proportioned γ-fiber forms in the annealed samples.展开更多
A new intelligent control scheme for hot strip coiling temperature is presented. In this scheme, the prediction mode1 of finishing temperature and the presetting model of main cooling zone are establish based on BP ne...A new intelligent control scheme for hot strip coiling temperature is presented. In this scheme, the prediction mode1 of finishing temperature and the presetting model of main cooling zone are establish based on BP neural network, the feed-forward open-loop control model of main cooling zone is constructed based on T-S fuzzy neural network, a new improved structure of T-S fuzzy neural network is developed, and the feedback close-loop control model of precision cooling zone is obtained based on fuzzy control. The effectiveness of the proposed scheme has been demonstrated by computer simulation with a satisfactory result.展开更多
The effects of cooling rate and coiling temperature on microstructure and mechanical properties of a plain carbon steel were investigated by combining metallography and tensile experiments. The results indicate that f...The effects of cooling rate and coiling temperature on microstructure and mechanical properties of a plain carbon steel were investigated by combining metallography and tensile experiments. The results indicate that ferrite grain size is refined and bainite transformation occurs to ensure high strength and elongation, as the cooling rate is quick enough. Yield strength and tensite strength improve with the decreased finish cooling temperature, but the elongation decreases too significantly to meet the requirements. Thus, the cooling rate must be quick enough, and the appropriate coiling temperature should be carefully selected to obtain refined ferrite and a small amount of bainite to improve the strength while the plasticity is also ensured. Under this condition, the Mn element concentration can be reduced to save cost or produce higher strength steel with same chemical composition.展开更多
In this paper, the effect of hot-rolling processing parameters on the post-rolling transformation behavior of C-Mn-Cr-Cu weather-resistant martensitic steel was investigated.Results indicate that the post-rolling tran...In this paper, the effect of hot-rolling processing parameters on the post-rolling transformation behavior of C-Mn-Cr-Cu weather-resistant martensitic steel was investigated.Results indicate that the post-rolling transformation behavior, particularly the post-coiling transformation behavior, strongly depends on the coiling temperature.Under a high coiling temperature, ferrite/pearlite transformation was mainly observed with a low trans-formation speed and transformation dilation after coiling.With decreasing coiling temperature, the proportion of bainite transformation increased with an increased transformation speed and transformation dilation.The dependence of transformation behavior on the coiling temperature could be one of the most important reasons behind the coil collapse of the experimental steel.The optimization of hot-rolling and coiling processing parameters of the steel strip, including laminar flow cooling, coiling temperature, and suspension time on the winding machine, can signi-ficantly reduce the transformation dilation of the steel after hot rolling, thus effectively controlling the coil collapse of the steel.展开更多
Background:To evaluate the efficacy of stent-assisted coiling(SAC)for the treatment of carotid ophthalmic segment aneurysm segment aneurysms(OSAs)of the internal carotid artery(ICA)through detailed long-term follow-up...Background:To evaluate the efficacy of stent-assisted coiling(SAC)for the treatment of carotid ophthalmic segment aneurysm segment aneurysms(OSAs)of the internal carotid artery(ICA)through detailed long-term follow-up of a large patient cohort.Methods:We retrospectively analyzed 88 consecutive patients with OSAs between January 2009 and January 2020 at our center.Angiographic results were evaluated using the modified Raymond grading system and clinical outcomes were evaluated using the mRS scale.The primary endpoints were major aneurysm recurrence and poor clinical outcomes for at least 18 months of follow-up.The patients were asked to attend clinical follow-up assessments and possibly undergo DSA or MR via telephone.Results:We enrolled 88 patients with 99 OSAs treated with coiling,of whom 76 were treated with SAC.The coiling procedures were successful in all 88 patients.Overall,complications occurred in 8 patients(9.1%).No procedure-related mortality was observed.67(76.1%)experienced immediate aneurysm occlusion at the end of the procedure.Long-term angiographic follow-up(18 months)was available in 45/88 aneurysms(51%)(average 18.7±5.2 months).Four patients continued their follow-up for 5 years after initial aneurysm treatment.After a clinical follow-up time of 28.7 months(range,12-51 months),85 patients(95.5%)achieved favorable clinical outcomes(mRS scores of 0-2).Conclusions:This study indicates that SAC treatment is a safe and effective therapeutic alternative for ruptured and unruptured OSAs.The procedural risks are low with relatively long-term effectiveness.展开更多
To improve the precision of the coiling temperature and the performance of the feedback control system with long pure time delay on hot strip mills, we analyzed the design process of the Dahlin algorithm in detail. Th...To improve the precision of the coiling temperature and the performance of the feedback control system with long pure time delay on hot strip mills, we analyzed the design process of the Dahlin algorithm in detail. The coiling temperature curves controlled by the PID algorithm and Dahlin algorithm were simulated and compared, which showed that the control precision with the Dahlin algorithm was higher than that with the PID algorithm. That was further verified by the production practice.展开更多
A measure called the Uncertainty in Unruptured Intracranial Aneurysm Patients Undergoing Endovascular Coiling Scale (UUIACS) was developed and its validity and reliability were examined. The 49 questions that comprise...A measure called the Uncertainty in Unruptured Intracranial Aneurysm Patients Undergoing Endovascular Coiling Scale (UUIACS) was developed and its validity and reliability were examined. The 49 questions that comprised the original draft of the UUIACS were created based on interview data. Based on data from 172 participants, exploratory and confirmatory factor analyses were conducted. As a result of exploratory factor analysis, the UUIACS e retained 17 items and extracted four factors (“Lack of decision-making cues”, “Lack of information and complexity of information interpretation”, “The ambiguous nature of the disease”, and “The unpredictable living with UIA”). All of the UUIACS items showed adequate internal consistency. Between the UUIAC scale and the Universal Uncertainty in Illness Scale (UUIS), the Health Locus of Control (HLC) scale, and the SF-36v2® (Japanese version), positive correlations were found between the UUIACS and UUIS, and the HLC scale at a 1% significance level indicating concurrent validity. According to confirmatory factor analysis, the UUIACS had an acceptable goodness of fit. Given these findings, the UUIACS was judged to have satisfied the criteria for use in a clinical setting, although further investigation was required.展开更多
Background: Potentially lethal, aneurysmal subarachnoid hemorrhage has a bad prognosis for many individuals. Over the past few decades, endovascular and surgical interventions have been developed, including surgical c...Background: Potentially lethal, aneurysmal subarachnoid hemorrhage has a bad prognosis for many individuals. Over the past few decades, endovascular and surgical interventions have been developed, including surgical clipping, and endovascular coiling. Patients who have aSAH are also susceptible to delayed cerebral ischemia and cerebral vasospasm. The aim of this study is to compare the outcome of endovascular coiling with surgical clipping in patients with SAH, specifically in relation to prevalence of vasospasm, in the country of Georgia. Method: In this study, we present a retrospective review of the outcomes of 217 patients with acute subarachnoid hemorrhage who underwent endovascular coiling or surgical clipping. The data were gathered from patients who are admitted to New Vision University Hospital and Caucasus Medical Center in Tbilisi, Georgia, between 2017 and 2022. Results: Vasospasm was prevalent in 217 of the patients who had aneurysmal rupture when they first appeared. Endovascular coiling or surgical clipping was used to treat aneurysmal rupture. In our sample, 24.81 percent of patients who underwent coiling experienced vasospasm after 14 days, compared to 31.25 percent of patients who underwent clipping. After endovascular coiling and surgical clipping, the severity of vasospasm was only slightly different, according to Lindegaard ratios. Finally, 32 patients (23.35 percent) died after coiling whereas 55 patients (68.75 percent) died within three decades of clipping. Conclusion: After 5 years of data collection, this study has demonstrated the most favorable option for treatment is endovascular coiling. However, the treatment choice takes multiple factors into account, and clipping is not ideal for some ruptured aneurysms. Despite the fact that endovascular coiling is usually successful and minimally invasive, complications can occur and additional monitoring and potential surgical intervention are indicated.展开更多
Objective: To evaluate and compare the outcomes of microsurgical clipping and endovascular coiling of ruptured anterior cerebral circulation aneurysms. Methods: The current study retrospectively included 61 patients p...Objective: To evaluate and compare the outcomes of microsurgical clipping and endovascular coiling of ruptured anterior cerebral circulation aneurysms. Methods: The current study retrospectively included 61 patients presented with subarachnoid hemorrhage (SAH), treated by clipping or coiling for ruptured aneurysms located in anterior circulation. Anatomic outcome and post-operative ischemic events were evaluated. The primary clinical outcomes were evaluated as operative complications while the secondary clinical outcome was evaluated by modified Rankin scale (mRS) at discharge. Results: Of 61 ruptured aneurysms, 47 and 14 were treated by surgery and coiling, respectively. The average follow-up duration was 19.1 ± 18.6 months for clipping and 21.7 ± 14.8 months for coiling. Complete occlusion was greater in surgery group (80.8%) than endovascular group (21.4%). Re-growth occurred in 2 cases of the coiling group only. Ischemic events were encountered in both groups;silent ones were higher in coiling group (21.4%) than in clipping group (6.3%), while symptomatic ones were higher in the clipping group (49%). Good outcome (mRS 0 - 2) was 51% and 71.4% after clipping and coiling respectively. Postoperative hospital period was longer after clipping (P = 0.04). Conclusions: For anterior circulation ruptured aneurysms, both treatments are feasible, coiling showed lower rate of morbidity while clipping results were better regarding durability and recurrence. Coil embolization may be preferred, which is the current point proved by the RCT like ISAT, but if you choose the patients carefully and find out the optimal candidate for the clipping, the clipping is still enough feasible as a mainstream.展开更多
The present work aimed to investigate the effect of coiling process conditions on microstructure development in a low-Si content TRIP (transformation-induced plasticity)-assisted steel after thermomechanical process...The present work aimed to investigate the effect of coiling process conditions on microstructure development in a low-Si content TRIP (transformation-induced plasticity)-assisted steel after thermomechanical processing. In this framework, compression samples which were deformed above Tnr and then intercritically annealed were held isothermally for different durations at temperatures below bainite transformation start temperature. Microstructure of samples were characterized by optical and electron microscopy, XRD (X-ray diffraction) and M6ssbauer spectroscopy. The results indicated that due to low-silicon content of the present steel, the incomplete bainite reaction phenomena was not observed and, hence, the maximum carbon enrichment of residual austenite was achieved in the samples which held for short durations. It was also shown that the maximum carbon enrichment and volume fraction of residual austenite were achieved at intermediate bainite hold temperature of 450 ℃ as the result of competing phenomena, such as microstructural refinement, dislocation density, carbide precipitation and growth.展开更多
Objective To investigate the application of assisted coiling techniques in the treatment of complex intracranial aneurysms. Methods From Jun. 2007 to Aug. 2010,36 patients with 41 complex intracranial aneurysms were t...Objective To investigate the application of assisted coiling techniques in the treatment of complex intracranial aneurysms. Methods From Jun. 2007 to Aug. 2010,36 patients with 41 complex intracranial aneurysms were treated by varient endovascular methods,including balloon, stent-assisted coiling and double microcatheter coilingtechniques. Results Among the展开更多
Short suspension system has an indispensable effect on vehicle handling and ride,so,optimization of vehicle suspension system is one of the most effective methods,which could considerably enhance the vehicle stability...Short suspension system has an indispensable effect on vehicle handling and ride,so,optimization of vehicle suspension system is one of the most effective methods,which could considerably enhance the vehicle stability and controllability.Motion control,stability maintenance and ride comfort improvement are fundamental issues in design of suspension system of off-road vehicles.In this work,a dependent suspension system mostly used in off-road vehicles is modeled using Trucksim software.Then,geometric parameters of suspension system are optimized using integrated anti-roll bar and coiling spring in a way that ride comfort,handling and stability of vehicle are improved.The simulation results of suspension system and variations of geometric parameters due to road roughness and different steering angles are presented in Trucksim and effects of optimization of suspension system during various driving maneuvers in both optimized and un-optimized conditions are compared.The simulation results indicate that the type of suspension system and geometric parameters have significant effect on vehicle performance.展开更多
Objective:This study aimed to evaluate the clinical and angiographic outcomes of aneurysms that were completely or near-completely embolized and ascertain whether complete embolization is important in the stent-assist...Objective:This study aimed to evaluate the clinical and angiographic outcomes of aneurysms that were completely or near-completely embolized and ascertain whether complete embolization is important in the stent-assisted coiling(SAC)of intracranial aneurysms.Methods:This retrospective study enrolled 390 patients(417 aneurysms).Among them,complete(100%)or nearcomplete(>90%)angiographic obliteration of the aneurysms on immediate angiography was accomplished.Baseline characteristics,complications,angiography follow-up results,and clinical outcomes were analyzed.Results:Cumulative adverse events occurred in 30 patients(7.7%),including thromboembolic complications in 17(4.4%),intraoperative rupture in 10(2.6%),and others in 3(0.8%).Statistical analyses revealed an increased intraprocedural rupture rate in the initial completely occluded aneurysms(5.6%compared with 1.0%).The incidence of cumulative adverse events was higher in patients with completely occluded aneurysms(11.1%)than in those with near-completely occluded aneurysms(5.5%).Angiography follow-up was available for 173 aneurysms.Aneurysm occlusion status at follow-up was correlated with stent placement(p?0.000,odds ratio?5.847),size(p?0.000,odds ratio?6.446 for tiny aneurysms;and p?0.001,odds ratio?5.616 for small aneurysms),and initial aneurysm occlusion status(p?0.001,odds ratio?3.436).Complete occlusion at followup was seen in 82.6%of the initial complete occlusion group versus 63.0%of the initial near-complete occlusion group.The incidence of complete occlusion at follow-up was higher in the initial completely occluded aneurysms with SAC(100%)than in the initial completely occluded aneurysms with non-SAC(65.2%).Conclusions:Initial complete treatment may lead to higher complication rates and good clinical outcomes at follow-up.Stent placement may enhance progressive aneurysm occlusion.Initial complete occlusion with SAC can provide durable closure at follow-up.展开更多
The plant-pollinator‘arms race’model posits that a major driver of the evolution of elongated corollas in flowers is reciprocal selection for‘morphological fit’between pollinator-tongue length and access distance ...The plant-pollinator‘arms race’model posits that a major driver of the evolution of elongated corollas in flowers is reciprocal selection for‘morphological fit’between pollinator-tongue length and access distance to nectar(usually corolla-tube length).Evidence for the pollinator-mediated selection on tube length and evolution of multiple,correlated floral traits remains inconclusive.To gain possible insights into the strength of stabilizing selection by assessing standing phenotypic variation,we measured a series of functionally important floral traits,including corolla tube length and‘effective’tube depth and degree of style coiling.We then calculated coefficients of variation(CV)for these traits in three field populations of R.schneideriana.Unlike in most long-tubed flowers,the bottom part of the corolla tube is completely occupied by the style,with no room for nectar.The length of this portion of the corolla tube was more variable(higher CV)than the upper part of the corolla tube,suggesting that functional tube depth was under stronger stabilizing selection.The degree of style coiling was negatively related to the corolla-tube length in all three populations of R.schneideriana,suggesting that there may be conflicting selection acting on style length and corolla-tube length,which are otherwise usually tightly correlated.Given the lack of nectar in the flowers of this species,the long corolla tubes and long styles may represent morphological holdovers from ancestors that were pollinated by long-tongued pollinators,as is still seen in related species in the western Himalayas.展开更多
Fiber strain sensors with robust sensing performance are indispensable for human-machine interactions in the electronic textiles.However,current fiber strain sensors are confronted with the challenges of unavoidable d...Fiber strain sensors with robust sensing performance are indispensable for human-machine interactions in the electronic textiles.However,current fiber strain sensors are confronted with the challenges of unavoidable deterioration of functional sensing components during wearable and extreme environments,resulting in unsatisfactory stability and durability.Here,we present a robust fiber strain sensor based on the mutual inductance effect.The sensor is assembled by designing coaxial helical coils around an elastic polyurethane fiber.When stretching the fiber sensor,the strain is detected by recording the voltage changes in the helical coils due to the variation in magnetic flux.The resultant fiber strain sensor shows high linearity(with a linear regression coefficient of 0.99)at a large strain of 100%,and can withstand various extreme environmental conditions,such as high/low temperatures(from-30℃to 160℃),and severe deformations,such as twisting and pressing(with a pressure of 500 N/cm).The long-term cyclic stability of our fiber strain sensor(100,000 cycles at a strain of 100%)is superior to that of most reported flexible resistive and capacitive strain sensors.Finally,the mass-produced fiber strain sensors are woven into a smart textile system to accurately capture gestures.展开更多
Objective To compare the differences of therapeutic effect of chronic fatigue syndrome (CFS) treated with the combined therapy of Panlongci (coiling dragon needling) and cupping on back and the western medicine th...Objective To compare the differences of therapeutic effect of chronic fatigue syndrome (CFS) treated with the combined therapy of Panlongci (coiling dragon needling) and cupping on back and the western medicine therapy with prednisone. Methods Seventy-two cases were randomly divided into 2 groups of acupuncture-cupping group (37 cases) and prednisone group (35 cases). In acupuncture-cupping group, Jiaji points (夹脊 EX-B 2) of the level of T1–L5 were applied with coiling dragon needling once a day, combining with moving cupping on back once every two days. In prednisone group, prednisone tablets of 10 mg were orally taken at 8:00 am everyday. Seven days were counted as one treatment course, and 2 courses were carried on totally. FS-14 scale and BELL’s CFS integral table were applied to evaluate the fatigue degree of patients before and after the treatment, and the therapeutic effects of both groups were compared. Results After one course of treatment, the BELL’s scores of both groups were obviously improved (both P0.01), but there was no significant difference between the 2 groups (P0.05); after 2 courses of treatment, the BELL’s score in acupuncture-cupping group improved more obviously than that of the prednisone group (P0.05), and the total effective rate of 91.9% (34/37) in acupuncture-cupping group was superior to that of 71.4% (25/35) in prednisone group (P0.05). Conclusion The therapeutic effect of chronic fatigue syndrome treated with coiling dragon needling and moving cupping on back is positive, which is superior to that of prednisone with oral administration.展开更多
Many strip materials are coiled after rolling process. The stresses are imposed on the material wound on the automatically controlled collapse mandrel under the coiling tension. The coiling process can be described by...Many strip materials are coiled after rolling process. The stresses are imposed on the material wound on the automatically controlled collapse mandrel under the coiling tension. The coiling process can be described by three typical cases: winding without automatic adjustment, winding with automatic adjustment and after mandrel removal. A new model of equations for predicting the stresses during the strip coiling process is built by consideration of the three cases respectively. By solving the equations of different typical cases, the radial stresses and tangential stress of the layers of coil can be calculated. Also, the coiling parameters, such as strip thickness, coiling tension and necking critical pressure, affecting the coil performance are investigated. It is believed that the present model can be used for design and control of the automatically controlled collapse mandrel.展开更多
基金supported by grant of Changzhou science and technology projects of social development (No. CS2007203)
文摘Prompt diagnosis and therapy of aneurysms are critical for patients with nontraumatic subarachnoid hemorrhage (SAH).The aim of our study was to assess the clinical usefulness of multislice computed tomography angiography (CTA) in the surgical and endovascular treatment of intracranial aneurysms.A total of 195 cases with 206 intracranial aneurysms underwent CTA.Fifty (24%) aneurysms underwent surgical clipping while 156 (76%) aneurysms underwent endovascular coiling.In the five missed aneurysms at digital substraction angiography and the nine aneurysms with mass intracerebral hematomas,surgical treatment was successfully performed based on 16-slice CTA alone,and the other 36 aneurysms were clipped on the main basis of the CTA.The intraoperative findings correlated well with the CTA findings and all aneurysms were clipped successfully.Sixteen-slice CTA image information has been shown to determine the choice of aneurysm therapy and assist the surgical and endovascular treatment of intracranial aneurysms.
基金Funded by the National Natural Science Foundation of China(No.51501056)Natural Science Foundation of Hebei Province(No.E2016209341)+2 种基金Educational Commission of Hebei Province(No.BJ2014031)Project of Science and Technology of Tangshan(Nos.14130243B and 15130202C)Foundation of North China University of Science and Technology(No.JP201510)
文摘The effects of hot-strip coiling temperature on Ti(C,N) precipitation, texture and hydrogen permeation behavior in DC06 EK enamel steel were investigated by TEM, EBSD test and electrochemical hydrogen permeation experiment. It was found that the Ti(C,N) particles in hot-strip coarsened with increasing coiling temperature, whereas after cold-rolling and annealing, the size difference of Ti(C,N) particles was lessened. The hot-strip coiling temperature has a significant impact on the recrystallized texture in the subsequent cold-rolled and annealed sheet. Hot-strip using high temperature(700 ℃) coiling leads to strong {111} recrystallized texture in annealed sheet, with peak intensity 9.2. On the contrary, in annealed sheets using hot-strip coiling at 650 ℃, their {111} recrystallized textures were weaker, which was also reflected in their rmvalues. Even though the hydrogen diffusion coefficient is slightly lower(7.76×10^(-5) mm^2/s) in annealed sheet using low temperature coiling(600 ℃), appropriately higher coiling temperature is more suitable for DC06 EK enamel steel combining both good drawability and fish-scale resistance.
基金National Natural Science Foundation of China for financial support, under Grant No. 50104004.
文摘The effect of coiling temperatures on the evolution of texture in Ti-IF steel during ferritic hot rolling, cold rolling and annealing was studied. It was found that texture evolution at high temperature coiling is absolutely different from that at low temperature one. The hot band texture includes a strong α-fiber as well as a weak γ-fiber after ferritic hot rolling and low temperature coiling. Both of them intensify after cold rolling and a γ-fiber with peak at {111}〈112〉 is the main texture of annealed samples. However, the main component of the hot band texture after high temperature coiling is v-fiber. After cold rolling, the intensity of γ texture reduces; α fiber (except {111}〈110〉 component) intensifies and a strong and well-proportioned γ-fiber forms in the annealed samples.
文摘A new intelligent control scheme for hot strip coiling temperature is presented. In this scheme, the prediction mode1 of finishing temperature and the presetting model of main cooling zone are establish based on BP neural network, the feed-forward open-loop control model of main cooling zone is constructed based on T-S fuzzy neural network, a new improved structure of T-S fuzzy neural network is developed, and the feedback close-loop control model of precision cooling zone is obtained based on fuzzy control. The effectiveness of the proposed scheme has been demonstrated by computer simulation with a satisfactory result.
文摘The effects of cooling rate and coiling temperature on microstructure and mechanical properties of a plain carbon steel were investigated by combining metallography and tensile experiments. The results indicate that ferrite grain size is refined and bainite transformation occurs to ensure high strength and elongation, as the cooling rate is quick enough. Yield strength and tensite strength improve with the decreased finish cooling temperature, but the elongation decreases too significantly to meet the requirements. Thus, the cooling rate must be quick enough, and the appropriate coiling temperature should be carefully selected to obtain refined ferrite and a small amount of bainite to improve the strength while the plasticity is also ensured. Under this condition, the Mn element concentration can be reduced to save cost or produce higher strength steel with same chemical composition.
文摘In this paper, the effect of hot-rolling processing parameters on the post-rolling transformation behavior of C-Mn-Cr-Cu weather-resistant martensitic steel was investigated.Results indicate that the post-rolling transformation behavior, particularly the post-coiling transformation behavior, strongly depends on the coiling temperature.Under a high coiling temperature, ferrite/pearlite transformation was mainly observed with a low trans-formation speed and transformation dilation after coiling.With decreasing coiling temperature, the proportion of bainite transformation increased with an increased transformation speed and transformation dilation.The dependence of transformation behavior on the coiling temperature could be one of the most important reasons behind the coil collapse of the experimental steel.The optimization of hot-rolling and coiling processing parameters of the steel strip, including laminar flow cooling, coiling temperature, and suspension time on the winding machine, can signi-ficantly reduce the transformation dilation of the steel after hot rolling, thus effectively controlling the coil collapse of the steel.
基金supported by grants from the National Natural Science Foundation of China,grant no. 81370041, 81771233, 81671655the Outstanding Clinical Discipline Project of Shanghai Pudonggrant no.PWYgy2018-04.
文摘Background:To evaluate the efficacy of stent-assisted coiling(SAC)for the treatment of carotid ophthalmic segment aneurysm segment aneurysms(OSAs)of the internal carotid artery(ICA)through detailed long-term follow-up of a large patient cohort.Methods:We retrospectively analyzed 88 consecutive patients with OSAs between January 2009 and January 2020 at our center.Angiographic results were evaluated using the modified Raymond grading system and clinical outcomes were evaluated using the mRS scale.The primary endpoints were major aneurysm recurrence and poor clinical outcomes for at least 18 months of follow-up.The patients were asked to attend clinical follow-up assessments and possibly undergo DSA or MR via telephone.Results:We enrolled 88 patients with 99 OSAs treated with coiling,of whom 76 were treated with SAC.The coiling procedures were successful in all 88 patients.Overall,complications occurred in 8 patients(9.1%).No procedure-related mortality was observed.67(76.1%)experienced immediate aneurysm occlusion at the end of the procedure.Long-term angiographic follow-up(18 months)was available in 45/88 aneurysms(51%)(average 18.7±5.2 months).Four patients continued their follow-up for 5 years after initial aneurysm treatment.After a clinical follow-up time of 28.7 months(range,12-51 months),85 patients(95.5%)achieved favorable clinical outcomes(mRS scores of 0-2).Conclusions:This study indicates that SAC treatment is a safe and effective therapeutic alternative for ruptured and unruptured OSAs.The procedural risks are low with relatively long-term effectiveness.
文摘To improve the precision of the coiling temperature and the performance of the feedback control system with long pure time delay on hot strip mills, we analyzed the design process of the Dahlin algorithm in detail. The coiling temperature curves controlled by the PID algorithm and Dahlin algorithm were simulated and compared, which showed that the control precision with the Dahlin algorithm was higher than that with the PID algorithm. That was further verified by the production practice.
文摘A measure called the Uncertainty in Unruptured Intracranial Aneurysm Patients Undergoing Endovascular Coiling Scale (UUIACS) was developed and its validity and reliability were examined. The 49 questions that comprised the original draft of the UUIACS were created based on interview data. Based on data from 172 participants, exploratory and confirmatory factor analyses were conducted. As a result of exploratory factor analysis, the UUIACS e retained 17 items and extracted four factors (“Lack of decision-making cues”, “Lack of information and complexity of information interpretation”, “The ambiguous nature of the disease”, and “The unpredictable living with UIA”). All of the UUIACS items showed adequate internal consistency. Between the UUIAC scale and the Universal Uncertainty in Illness Scale (UUIS), the Health Locus of Control (HLC) scale, and the SF-36v2® (Japanese version), positive correlations were found between the UUIACS and UUIS, and the HLC scale at a 1% significance level indicating concurrent validity. According to confirmatory factor analysis, the UUIACS had an acceptable goodness of fit. Given these findings, the UUIACS was judged to have satisfied the criteria for use in a clinical setting, although further investigation was required.
文摘Background: Potentially lethal, aneurysmal subarachnoid hemorrhage has a bad prognosis for many individuals. Over the past few decades, endovascular and surgical interventions have been developed, including surgical clipping, and endovascular coiling. Patients who have aSAH are also susceptible to delayed cerebral ischemia and cerebral vasospasm. The aim of this study is to compare the outcome of endovascular coiling with surgical clipping in patients with SAH, specifically in relation to prevalence of vasospasm, in the country of Georgia. Method: In this study, we present a retrospective review of the outcomes of 217 patients with acute subarachnoid hemorrhage who underwent endovascular coiling or surgical clipping. The data were gathered from patients who are admitted to New Vision University Hospital and Caucasus Medical Center in Tbilisi, Georgia, between 2017 and 2022. Results: Vasospasm was prevalent in 217 of the patients who had aneurysmal rupture when they first appeared. Endovascular coiling or surgical clipping was used to treat aneurysmal rupture. In our sample, 24.81 percent of patients who underwent coiling experienced vasospasm after 14 days, compared to 31.25 percent of patients who underwent clipping. After endovascular coiling and surgical clipping, the severity of vasospasm was only slightly different, according to Lindegaard ratios. Finally, 32 patients (23.35 percent) died after coiling whereas 55 patients (68.75 percent) died within three decades of clipping. Conclusion: After 5 years of data collection, this study has demonstrated the most favorable option for treatment is endovascular coiling. However, the treatment choice takes multiple factors into account, and clipping is not ideal for some ruptured aneurysms. Despite the fact that endovascular coiling is usually successful and minimally invasive, complications can occur and additional monitoring and potential surgical intervention are indicated.
文摘Objective: To evaluate and compare the outcomes of microsurgical clipping and endovascular coiling of ruptured anterior cerebral circulation aneurysms. Methods: The current study retrospectively included 61 patients presented with subarachnoid hemorrhage (SAH), treated by clipping or coiling for ruptured aneurysms located in anterior circulation. Anatomic outcome and post-operative ischemic events were evaluated. The primary clinical outcomes were evaluated as operative complications while the secondary clinical outcome was evaluated by modified Rankin scale (mRS) at discharge. Results: Of 61 ruptured aneurysms, 47 and 14 were treated by surgery and coiling, respectively. The average follow-up duration was 19.1 ± 18.6 months for clipping and 21.7 ± 14.8 months for coiling. Complete occlusion was greater in surgery group (80.8%) than endovascular group (21.4%). Re-growth occurred in 2 cases of the coiling group only. Ischemic events were encountered in both groups;silent ones were higher in coiling group (21.4%) than in clipping group (6.3%), while symptomatic ones were higher in the clipping group (49%). Good outcome (mRS 0 - 2) was 51% and 71.4% after clipping and coiling respectively. Postoperative hospital period was longer after clipping (P = 0.04). Conclusions: For anterior circulation ruptured aneurysms, both treatments are feasible, coiling showed lower rate of morbidity while clipping results were better regarding durability and recurrence. Coil embolization may be preferred, which is the current point proved by the RCT like ISAT, but if you choose the patients carefully and find out the optimal candidate for the clipping, the clipping is still enough feasible as a mainstream.
文摘The present work aimed to investigate the effect of coiling process conditions on microstructure development in a low-Si content TRIP (transformation-induced plasticity)-assisted steel after thermomechanical processing. In this framework, compression samples which were deformed above Tnr and then intercritically annealed were held isothermally for different durations at temperatures below bainite transformation start temperature. Microstructure of samples were characterized by optical and electron microscopy, XRD (X-ray diffraction) and M6ssbauer spectroscopy. The results indicated that due to low-silicon content of the present steel, the incomplete bainite reaction phenomena was not observed and, hence, the maximum carbon enrichment of residual austenite was achieved in the samples which held for short durations. It was also shown that the maximum carbon enrichment and volume fraction of residual austenite were achieved at intermediate bainite hold temperature of 450 ℃ as the result of competing phenomena, such as microstructural refinement, dislocation density, carbide precipitation and growth.
文摘Objective To investigate the application of assisted coiling techniques in the treatment of complex intracranial aneurysms. Methods From Jun. 2007 to Aug. 2010,36 patients with 41 complex intracranial aneurysms were treated by varient endovascular methods,including balloon, stent-assisted coiling and double microcatheter coilingtechniques. Results Among the
文摘Short suspension system has an indispensable effect on vehicle handling and ride,so,optimization of vehicle suspension system is one of the most effective methods,which could considerably enhance the vehicle stability and controllability.Motion control,stability maintenance and ride comfort improvement are fundamental issues in design of suspension system of off-road vehicles.In this work,a dependent suspension system mostly used in off-road vehicles is modeled using Trucksim software.Then,geometric parameters of suspension system are optimized using integrated anti-roll bar and coiling spring in a way that ride comfort,handling and stability of vehicle are improved.The simulation results of suspension system and variations of geometric parameters due to road roughness and different steering angles are presented in Trucksim and effects of optimization of suspension system during various driving maneuvers in both optimized and un-optimized conditions are compared.The simulation results indicate that the type of suspension system and geometric parameters have significant effect on vehicle performance.
文摘Objective:This study aimed to evaluate the clinical and angiographic outcomes of aneurysms that were completely or near-completely embolized and ascertain whether complete embolization is important in the stent-assisted coiling(SAC)of intracranial aneurysms.Methods:This retrospective study enrolled 390 patients(417 aneurysms).Among them,complete(100%)or nearcomplete(>90%)angiographic obliteration of the aneurysms on immediate angiography was accomplished.Baseline characteristics,complications,angiography follow-up results,and clinical outcomes were analyzed.Results:Cumulative adverse events occurred in 30 patients(7.7%),including thromboembolic complications in 17(4.4%),intraoperative rupture in 10(2.6%),and others in 3(0.8%).Statistical analyses revealed an increased intraprocedural rupture rate in the initial completely occluded aneurysms(5.6%compared with 1.0%).The incidence of cumulative adverse events was higher in patients with completely occluded aneurysms(11.1%)than in those with near-completely occluded aneurysms(5.5%).Angiography follow-up was available for 173 aneurysms.Aneurysm occlusion status at follow-up was correlated with stent placement(p?0.000,odds ratio?5.847),size(p?0.000,odds ratio?6.446 for tiny aneurysms;and p?0.001,odds ratio?5.616 for small aneurysms),and initial aneurysm occlusion status(p?0.001,odds ratio?3.436).Complete occlusion at followup was seen in 82.6%of the initial complete occlusion group versus 63.0%of the initial near-complete occlusion group.The incidence of complete occlusion at follow-up was higher in the initial completely occluded aneurysms with SAC(100%)than in the initial completely occluded aneurysms with non-SAC(65.2%).Conclusions:Initial complete treatment may lead to higher complication rates and good clinical outcomes at follow-up.Stent placement may enhance progressive aneurysm occlusion.Initial complete occlusion with SAC can provide durable closure at follow-up.
基金This work was supported by the National Natural Science Foundation of China(grant nos.31270281,32030071)to SQHNNSFC(32071671)to ZYT.
文摘The plant-pollinator‘arms race’model posits that a major driver of the evolution of elongated corollas in flowers is reciprocal selection for‘morphological fit’between pollinator-tongue length and access distance to nectar(usually corolla-tube length).Evidence for the pollinator-mediated selection on tube length and evolution of multiple,correlated floral traits remains inconclusive.To gain possible insights into the strength of stabilizing selection by assessing standing phenotypic variation,we measured a series of functionally important floral traits,including corolla tube length and‘effective’tube depth and degree of style coiling.We then calculated coefficients of variation(CV)for these traits in three field populations of R.schneideriana.Unlike in most long-tubed flowers,the bottom part of the corolla tube is completely occupied by the style,with no room for nectar.The length of this portion of the corolla tube was more variable(higher CV)than the upper part of the corolla tube,suggesting that functional tube depth was under stronger stabilizing selection.The degree of style coiling was negatively related to the corolla-tube length in all three populations of R.schneideriana,suggesting that there may be conflicting selection acting on style length and corolla-tube length,which are otherwise usually tightly correlated.Given the lack of nectar in the flowers of this species,the long corolla tubes and long styles may represent morphological holdovers from ancestors that were pollinated by long-tongued pollinators,as is still seen in related species in the western Himalayas.
基金financially by Ministry of Science and Technology of the People's Republic of China(2022YFA1203001,2022YFA1203002)National Natural Science Foundation of China(T2321003,22335003,T2222005,22175042)Science and Technology Commission of Shanghai Municipality(21511104900).
文摘Fiber strain sensors with robust sensing performance are indispensable for human-machine interactions in the electronic textiles.However,current fiber strain sensors are confronted with the challenges of unavoidable deterioration of functional sensing components during wearable and extreme environments,resulting in unsatisfactory stability and durability.Here,we present a robust fiber strain sensor based on the mutual inductance effect.The sensor is assembled by designing coaxial helical coils around an elastic polyurethane fiber.When stretching the fiber sensor,the strain is detected by recording the voltage changes in the helical coils due to the variation in magnetic flux.The resultant fiber strain sensor shows high linearity(with a linear regression coefficient of 0.99)at a large strain of 100%,and can withstand various extreme environmental conditions,such as high/low temperatures(from-30℃to 160℃),and severe deformations,such as twisting and pressing(with a pressure of 500 N/cm).The long-term cyclic stability of our fiber strain sensor(100,000 cycles at a strain of 100%)is superior to that of most reported flexible resistive and capacitive strain sensors.Finally,the mass-produced fiber strain sensors are woven into a smart textile system to accurately capture gestures.
文摘Objective To compare the differences of therapeutic effect of chronic fatigue syndrome (CFS) treated with the combined therapy of Panlongci (coiling dragon needling) and cupping on back and the western medicine therapy with prednisone. Methods Seventy-two cases were randomly divided into 2 groups of acupuncture-cupping group (37 cases) and prednisone group (35 cases). In acupuncture-cupping group, Jiaji points (夹脊 EX-B 2) of the level of T1–L5 were applied with coiling dragon needling once a day, combining with moving cupping on back once every two days. In prednisone group, prednisone tablets of 10 mg were orally taken at 8:00 am everyday. Seven days were counted as one treatment course, and 2 courses were carried on totally. FS-14 scale and BELL’s CFS integral table were applied to evaluate the fatigue degree of patients before and after the treatment, and the therapeutic effects of both groups were compared. Results After one course of treatment, the BELL’s scores of both groups were obviously improved (both P0.01), but there was no significant difference between the 2 groups (P0.05); after 2 courses of treatment, the BELL’s score in acupuncture-cupping group improved more obviously than that of the prednisone group (P0.05), and the total effective rate of 91.9% (34/37) in acupuncture-cupping group was superior to that of 71.4% (25/35) in prednisone group (P0.05). Conclusion The therapeutic effect of chronic fatigue syndrome treated with coiling dragon needling and moving cupping on back is positive, which is superior to that of prednisone with oral administration.
文摘Many strip materials are coiled after rolling process. The stresses are imposed on the material wound on the automatically controlled collapse mandrel under the coiling tension. The coiling process can be described by three typical cases: winding without automatic adjustment, winding with automatic adjustment and after mandrel removal. A new model of equations for predicting the stresses during the strip coiling process is built by consideration of the three cases respectively. By solving the equations of different typical cases, the radial stresses and tangential stress of the layers of coil can be calculated. Also, the coiling parameters, such as strip thickness, coiling tension and necking critical pressure, affecting the coil performance are investigated. It is believed that the present model can be used for design and control of the automatically controlled collapse mandrel.