Research Progress of Key Technology of High-Speed and High Precision Motorized Spindles

High speed machining and high precision machining are two tendencies of themanufacturing technology worldwide. The motorized spindle is the core component of the machine toolsfor achieving the high speed and high precise machining, which affects the general developmentlevel of the machine tools to a great extent. Progress of the key techniques is reviewed in thispaper, in which the high speed and high precision spindle bearings, the dynamical and thermalcharacteristics of spindles, the design technique of the high frequency motors and the drivers, theanti-electromagnetic damage technique of the motors, and the machining and assembling technique areinvolved. Finally, tha development tendencies of the motorized spindles are presented.

AN OPTIMAL DESIGN OF RING SPINNING SPINDLES USING PROGRAM SAP84

In this paper, natural frequencies and vibration modes of spindl D1203 are calculated by us-ing structural analysis program SAP84. It is found that the second natural frequency of D1203spindle is too close to the range of working speed. In order to raise the second natural frequencyand to reduce the vibration noise, simple optimal design of several structural parameters are alsodiscussed by means of the orthogonal design method. It is shown that the better design is toshorten the length of the spindle blade appropriately and to increase the elasticity of its uppersupport.

THE MORPHOLOGICAL CHANGES IN MUSCLE SPINDLES AND ALTERATIONS IN CELL ACTIVITY OF THE RATS' RED NUCLEUS AFTER 2 WEEKS' SIMULATED WEIGHTLESSNESS

Objective To study the morphological changes of soleus muscle spindle and electrical activity of neurons in Red Nucleus(RN) of the rat after 2 weeks' simulated weightlessness, and to reveal the interaction between proprioceptive inputs of muscle spindles and reciprocal alterations in RN under simulated weightlessness. Methods Twenty female rats were exposed to weightlessness simulated by tail-suspension for 14 days (SW-14d). Body weight(200-220g) matched female rats were control group(Con). The morphological changes in isolated muscle spindle of soleus muscle, the discharges of red nucleus neurons were observed after 14d tail-suspensions by silver staining and extracellular recording respectively. Results Compared with control group ,the nerve ending of muscle spindle in SW-14d was distorted, degenerated and dissolved; the diameters of intrafusal fibers and capsule in equatorial region of soleus muscle spindles were diminished(P<0.05). The spontaneous cell activity and discharge of RN neurons (spikes/s) induced by afferent firing from muscle spindles after injection of succinylcholine were reduced after 2 weeks' simulated weightlessness respectively (18.44±5.96 vs. 10.19±6.88, 32.50±8.08 vs. 16.86±5.97, P<0.01). Conclusion The degeneration of muscle spindle induced by simulated weightlessness may be one of the causes that led to alterations in discharges of RN.

The Application of Visual Organization Principle in the Detection of Sleep Spindles

In order to detect the sleep spindles simply and efficiently, a novel time-domain approach to detect sleep spindles based on the principles of visual organization is proposed. The code idea of the visual organization is to organize the primary visual elements according to some rules of organization, and to form a more meaningful object of visual processing, as the input of next process. After the collected EEG is processed with the merging algorithm based on the principle of visual organization, it can extract the time-domain feature frequency and duration time better. Use these features with a simple algorithm to detect spindles achieving sensitivity of 92.5% and specificity of 98.1%, which verifies the validity of this method to detect the sleep spindles.

Sleep spindles detection from human sleep EEG signals using autoregressive (AR) model: a surrogate data approach

A new algorithm for the detection of sleep spindles from human sleep EEG with surrogate data approach is presented. Surrogate data ap-proach is the state of the art technique for nonlinear spectral analysis. In this paper, by developing autoregressive (AR) models on short segment of the EEG is described as a superposition of harmonic oscillating with damping and frequency in time. Sleep spindle events are detected, whenever the damping of one or more frequencies falls below a prede-fined threshold. Based on a surrogate data, a method was proposed to test the hypothesis that the original data were generated by a linear Gaussian process. This method was tested on human sleep EEG signal. The algorithm work well for the detection of sleep spindles and in addition the analysis reveals the alpha and beta band activities in EEG. The rigorous statistical framework proves essential in establishing these results.

Deficit of mitochondria-derived ATP during oxidative stress impairs mouse MII oocyte spindles

Although the role of oxidative stress in maternal aging and infertility has been suggested, the underlying mechanisms are not fully understood. The present study is designed to determine the relationship between mitochondrial function and spindle stability in metaphase II (MII) oocytes under oxidative stress. MII mouse oocytes were treated with H2O2 in the presence or absence of permeability transition pores (PTPs) blockers cyclosporin A (CsA). In addition, antioxidant N-acetylcysteine (NAC), F0/F1 synthase inhibitor oligomycin A, the mitochondria uncoupler carbonyl cyanide 4-trifluoro- methoxyphenylhydrazone (FCCP) or thapsigargin plus 2.5 mM Ca^2+ (Th+2.5 mM Ca^2+) were used in mechanistic studies. Morphologic analyses of oocyte spindles and chromosomes were performed and mitochondrial membrane potential (AWm), cytoplasmic free calcium concentration ([Ca^2+]c) and cytoplasmic ATP content within oocytes were also assayed. In a time- and H202 dose-dependent manner, disruption of meiotic spindles was found after oocytes were treated with H202, which was prevented by pre-treatment with NAC. Administration of H2O2 led to a dissipation of AWm, an increase in [Ca^2+]c and a decrease in cytoplasmic ATP levels. These detrimental responses of oocytes to H2O2 treatment could be blocked by pre-incubation with CsA. Similar to H2O2, both oligomycin A and FCCP dissipated AWm, decreased cytoplasmic ATP contents and disassembled MII oocyte spindles, while high [Ca^2+]c alone had no effects on spindle morphology. In conclusion, the decrease in mitochondria-derived ATP during oxidative stress may cause a disassembly of mouse MII oocyte spindles, presumably due to the opening of the mitochondrial PTPs.

Sensory reinnervation of muscle spindles after repair of tibial nerve defects using autogenous vein grafts

Motor reinnervation after repair of tibial nerve defects using autologous vein grafts in rats has previously been reported, but sensory reinnervation after the same repair has not been fully investigated. In this study, partial sensory reinnervation of muscle spindles was observed after repair of lO-mm left tibial nerve defects using autologous vein grafts with end-to-end anasto- mosis in rats, and functional recovery was confirmed by electrophysiological studies. There were no significant differences in the number, size, or electrophysiological function of reinnervated muscle spindles between the two experimental groups. These findings suggest that repair of short nerve defects with autologous vein grafts provides comparable results to immediate end-to-end anastomosis in terms of sensory reinnervation of muscle spindles.

Phosphorylated vasodilator-stimulated phosphoprotein is localized on mitotic spindles of the gastric cancer cell line SGC-7901

AIM： To elucidate the localization of vasodilator stimulated phosphoprotein （VASP）, a cytoskeletal organizing protein and a substrate of protein kinases A and G in mitotic gastric cancer cells. METHODS： Immunofluorescence microscopy was used to observe the localization of α-tubulin, VASP and Ser157 phosphorylated VASP （p-VASP） in interphase of mitotic gastric cancer of the cell line SGC-7901. RESULTS： Immunofluorescence staining showed that p-VASP but not VASP was co-localized with α-tubulin on spindle poles and fibers in prophase, metaphase and anaphase of the mitotic process of the gastric cancer cell line SGC-7901. H89, an inhibitor of protein kinases A and G, had no effect on the localization of p-VASP on the spindles. CONCLUSION： VASP may play a role in assembling and stabilizing the mitotic spindle of cells, and phosphorylation of the protein is the precondition for it to exert this function.

Experimental Study on Meiotic Spindles and Chromosomes of Mouse Mature (MⅡ) Stage Oocytes under Laser Scanning Confocal Microscopy

Taking the mouse as a model, the experimental method of observing the morphology of meiotic spindles and chromosomes in mature oocytes were investigated in order to evaluate the effects of various interventions on the quality of oocytes accurately and rapidly. Laser scanning confocal microscope （LSCM） was used to examine the meiotic spindles and chromosomes by the technologies of optical section and three-dimensional （3D） image reconstruction. The results showed that the configurations of meiotic spindles and chromosomes could be observed clearly by LSCM. The normal rate of meiotic spindles and chromosomes was 82% and 86% respectively. It was concluded that the LSCM was a valid instrument to observe the meiotic spindles and chromosomes of mature oocytes and could be used as a valid method to evaluate the quality of MⅡocytes.

Model of Rotation Accuracy of High-Speed Spindles on Ball Bearings

For the purpose to improve a design quality of high-speed spindle units, we have developed mathematical models and software to simulate a rotation accuracy of spindles running on ball bearings. In order to better understand the mechanics of ball bearings, the dynamic interaction of ball bearings and spindle unit, and the influence of the bearing imperfections on the spindle rotation accuracy, we have carried out computer aided analysis and experimental studies. When doing this, we have found that the spindle rotation accuracy can vary drastically with rotational speed. The influence of bearing preload has a secondary importance. Comparison of the results of these studies has demonstrated adequacy of the models developed to the real spindle units.

Presence of Meiotic Spindles Indicates Early Cleavage of Embryos

Objective To assess whether the detection of the meiotic spindle could anticipate the appearance of early cleavage. Methods Oocytes were obtained from stimulated ovaries of consenting patients undergoing oocytes retrieval for ICSI. Spindles were imaged with the Polscope. After ICSI, oocytes with or without spindles were cultured for examination of early cleavage and embryo development. A total of 328 oocytes from 50 cycles were examined with the Polscope and inseminated by ICSI. Results Spindles were imaged in 81.7% of oocytes. After ICSI, more oocytes with spindles （78.4%） fertilized normally than oocytes without spindles （53.3%） （P〈0. 001）. At 25-27 h post ICSI, more fertilized oocytes developed from oocytes with spindles （81.9%） were detected early cleavage than those from oocytes without spindles （28.1%） （P〈0.001）. Significantly more embryos with early cleavage （82.2%） developed to high quality embryos at d 3 compared with the embryos without early cleavage （48.3%） （P=0.001）. The value of rs related to the relationship between spindles and early cleavage was 0.420 （P〈0.001）. Conclusion The existing of the early cleavage may have a predictive value on the opportunity of high quality embryos and the existing of the spindle may have a predictive value in the appearance of early cleavage.

Engineered Spindles of Little Molecules Around Electrospun Nanofbers for Biphasic Drug Release

Biphasic drug release is a popular advanced drug controlled release profle that has been drawing increasing attention from many felds.Electrospun nanofbers and their derivatives can be act as a strong platform for developing biphasic release dosage forms.In this study,a modifed coaxial electrospinning was implemented,in which little molecule solutions that contain a drug ibuprofen(IBU)and polyethylene glycol(PEG)were exploited as a sheath fuid to surround the core solutions composed of polymer ethyl cellulose(EC)and IBU.The prepared nanofber-based structural hybrids,i.e.,engineered spindles-on-astring(SOS)products,were successfully created and subjected to a series of characterizations.Scanning electron microscopy and transmission electron microscopy results showed the engineered SOS structures.IBU and the carriers EC and PEG had good compatibility,as suggested by X-ray difraction and Fourier transform infrared spectroscopy assessments.In vitro dissolution tests verifed that the SOS products were able to provide a typical biphasic release profle,releasing 40%of the loaded IBU within 1 h in an immediate manner in the frst phase,and the rest of the IBU in a sustained manner in the second phase.A combined mechanism of erosion and difusion is proposed for manipulating the IBU molecule release behaviors.

Myocardial metastasis from ZEB1-and TWIST-positive spindle cell carcinoma of the esophagus:A case report

BACKGROUND Metastatic cardiac tumors are known to occur more frequently than primary cardiac tumors,however,they often remain asymptomatic and are commonly dis-covered on autopsy.Malignant tumors with a relatively high frequency of cardiac metastasis include mesothelioma,melanoma,lung cancer,and breast cancer,whereas reports of esophageal cancer with cardiac metastasis are rare.CASE SUMMARY The case of a 60-year-old man who complained of dysphagia is presented.Upper gastrointestinal endoscopy showed a submucosal tumor-like elevated lesion in the esophagus causing stenosis.Contrast-enhanced computed tomography showed left atrial compression due to the esophageal tumor,multiple liver and lung metastases,and a left pleural effusion.Pathological examination of a biopsy speci-men from the esophageal tumor showed spindle-shaped cells,raising suspicion of esophageal sarcoma.The disease progressed rapidly,and systemic chemotherapy was deemed necessary,however,due to his poor general condition,adminis-tration of cytotoxic agents was considered difficult.Given his high Combined Positive Score,nivolumab was administered,however,the patient soon died from the disease.The autopsy confirmed spindle cell carcinoma(SCC)of the esophagus and cardiac metastasis with similar histological features.Cancer stem cell markers,ZEB1 and TWIST,were positive in both the primary tumor and the cardiac metastasis.CONCLUSION To the best of our knowledge,there have been no prior reports of cardiac metastasis of esophageal SCC.This case highlights our experience with a patient with esophageal SCC who progressed rapidly and died from the disease,with the autopsy examination showing cardiac metastasis.

Pleomorphic leiomyosarcoma of the maxilla with metastasis to the colon:A case report

BACKGROUND Pleomorphic leiomyosarcomas make up around 8.6%of all leiomyosarcomas.They behave aggressively and often have poor prognoses.They can affect the gastrointestinal tract and retroperitoneum.To date,pleomorphic leiomyosarcoma involving the mesocolon have been reported in nine patients.CASE SUMMARY The patient was a 44-year-old man with a history of pleomorphic leiomyosarcoma of the left maxilla with metastasis to the lung and liver.His most recent positron emission tomography-computed tomography(PET-CT)scan showed uptake in the ascending and transverse colons.A colonoscopy revealed a 5.0 cm×3.5 cm×3.0 cm pedunculated polyp in the ascending colon.The polyp was removed using hot snare polypectomy technique and retrieved with Rothnet.Histopathologic examination of the polyp showed a metastatic pleomorphic leiomyosarcoma.CONCLUSION Uptake(s)on PET-CT in a patient with pleomorphic leiomyosarcoma should raise suspicion for metastasis.

Dynamic characteristics of hard disk drive spindles supported by hydrodynamic bearings

Most hard disk spindles currently used are supported by grease lubricated deep-groove ball bearings.However, in the trend of increasing spindle speed and reducing size and cost, the shortcomings of ball bearing spin-dles, such as high non-repeatable run out, high acoustic noise and short life time at high running speed, make themunsuitable for high performance hard disk drives (HDD). On the contrary, the dynamic characteristics of hydrody-namic bearing spindles are superior to that of ball bearing spindles. Therefore, they are considered to be the substi-tute of ball bearing spindles in HDD. In this paper, a simulative setup of HDD is build up. The dynamic characteristicsof liquid lubricated spiral groove bearing(SGB) spindles are studied. The effects of both operating condition andbearing clearance are investigated. It is found that running speed of the spindle has significant influence on its dy-namic performance, while the load has little influence. The effect of clearance is also evident.

An Efficient Sleep Spindle Detection Algorithm Based on MP and LSBoost

Sleep spindles are an electroencephalogram(EEG)biomarker of non-rapid eye movement(NREM)sleep and have important implications for clinical diagnosis and prognosis.However,it is challenging to accurately detect sleep spindles due to the complexity of the human brain and the uncertainty of neural mechanisms.To improve the reliability and objectivity of sleep spindle detection and to compensate for the limitations of manual annotation,this study proposes a new automatic detection algorithm based on Matching Pursuit(MP)and Least Squares Boosting(LSBoost),where the automatic sleep spindle detection algorithm can help reduce the visual annotation workload of sleep clinicians.Specifically,MP is a time-frequency analysis method suitable for extracting spindle wave characteristics,which can accurately locate spindle waves on a time-frequency plane.LSBoost is an ensemble learning classification method to deal with unbalanced data.Initially,theMP method is used to search for EEG segments that are possible spindle waves from the filtered raw EEG data.Then,the designed feature segments are thrown into the LSBoost classifier to further identify the real spindles from all candidates and output the final results.The proposed method is verified on the common public dataset DREAMS.The experiment results showthat the sensitivity and F1-scores based on the sample-based assessments achieve 68.2% and 55.4%,respectively.Furthermore,the Recall and F1-score based on the event assessments are 83.8% and 70.8%,respectively.These results show that the proposed algorithm is robust to the subject changes in the DREAMS dataset.In addition,it improves the quality of sleep spindle detection,which is expected to assist the manual marking of experts.

Ensemble Model for Spindle Thermal Displacement Prediction of Machine Tools

Numerous factors affect the increased temperature of a machine tool, including prolonged and high-intensity usage,tool-workpiece interaction, mechanical friction, and elevated ambient temperatures, among others. Consequently,spindle thermal displacement occurs, and machining precision suffers. To prevent the errors caused by thetemperature rise of the Spindle fromaffecting the accuracy during themachining process, typically, the factory willwarm up themachine before themanufacturing process.However, if there is noway to understand the tool spindle’sthermal deformation, the machining quality will be greatly affected. In order to solve the above problem, thisstudy aims to predict the thermal displacement of the machine tool by using intelligent algorithms. In the practicalapplication, only a few temperature sensors are used to input the information into the prediction model for realtimethermal displacement prediction. This approach has greatly improved the quality of tool processing.However,each algorithm has different performances in different environments. In this study, an ensemble model is used tointegrate Long Short-TermMemory (LSTM) with Support VectorMachine (SVM). The experimental results showthat the prediction performance of LSTM-SVM is higher than that of other machine learning algorithms.

Papillary thyroid carcinoma with nodular fasciitis-like stroma-an unusual variant with distinctive histopathology:A case report

BACKGROUND Papillary thyroid carcinoma(PTC)is regarded as a fairly common endocrine malignancy,which can be divided into different multiple variants due to wide morphologic differences.The majority of PTC variants have been reported,but PTC with nodular fasciitis-like stroma(NFS)is a rare pathological variant and has been infrequently reported in the relevant literature.This condition involves abundant reactive stromal components rich in spindle cells,which may account for 60%-80%of the tumor along with a typical papillary carcinoma.CASE SUMMARY A 44-year-old man presented with a 4-mo history of a palpable mass over the anterior aspect of the left neck,the tumor demonstrated gradual enlargement but was painless during the 4 mo prior to discovery.Thyroid function test results were normal.Physical examination showed an enormous and firm nodular mass in the left lobe of the thyroid gland extending to the level of the hyoid bone.Ultrasonography of the neck revealed a well-defined heterogeneous lesion measuring around 5.0 cm×4.0 cm with a hypoechoic complex nodule,decreased vascularity and speckles of microcalcification.The patient underwent left thyroidectomy with central compartment lymph node dissection.Final histopathological examination confirmed the diagnosis of PTC with extensive fibromatosis-like stroma combined with typical PTC.The patient was asymptomatic at the 3-mo follow-up.CONCLUSION PTC-NFS is a rare pathological variant and its diagnosis and prognosis may be similar to typical papillary carcinoma.

Fibromatosis-like metaplastic carcinoma of the breast:Two case reports

BACKGROUND Fibromatosis-like metaplastic carcinoma is classified as a rare type of metaplastic carcinoma of the breast by the 2012 WHO pathological and genetic classification criteria for breast tumors,which takes hyperplastic spindle cells as the main component and is often misdiagnosed as benign stromal proliferative lesions or benign mesenchymal tumors of the breast because of its mild morphology.Here,we collected the clinical data of 2 cases of fibromatosis-like metaplastic carcinoma of the breast and performed pathomorphological observation and immunohistochemical staining of the surgically resected specimens.According to the clinical features,imaging features,immunophenotype,diagnosis and differential diagnosis of 2 cases of fibromatosis-like metaplastic carcinoma of the breast,it was further differentiated.CASE SUMMARY Case 1:A 56-year-old postmenopausal female was admitted due to"right breast mass for over 1 year and local ulceration for over 1 mo".Physical examination showed a mass with a diameter of 4.5 cm×5.5 cm palpable at 2.5 cm from the nipple at 1 o'clock in the right breast.The skin on the surface of the mass ruptured about 3 cm,with a small amount of exudation and bleeding,less clear boundary,hard texture,fair activity,without obvious tenderness.No obvious abnormality was palpable in the left breast.No enlarged lymph nodes were palpable in the bilateral axillae and bilateral supraclavicular region.After removing the mass tissue,it was promptly sent to the pathology department for examination.Case 2:Female,52-years-old,premenopausal,admitted due to"right breast mass for more than 3 mo".Physical examination showed a 4.0 cm×4.0 cm diameter mass palpable at 2.0 cm of the nipple in the lower outer 7 o'clock direction of the right breast,with less clear boundary,hard texture,fair activity,no significant tenderness,no palpable significant abnormalities in the left breast,and no palpable enlarged lymph nodes in the bilateral axillae and bilateral supraclavicular region.The mass was resected and sent for pathological examination.Postoperative pathological examination revealed fibromatosis-like metaplastic carcinoma of the breast in both patient 1 and patient 2.No systemic therapy and local radiotherapy were performed after surgery,and no tumor recurrence or metastasis was observed.CONCLUSION Fibromatosis-like metaplastic carcinoma of the breast is a rare subtype of metaplastic carcinoma that is often misdiagnosed,and the diagnosis relies on medical history collection,complete sampling,and full use of immunohistochemical assessment.The risk of lymph node and distant metastasis is low,and the current treatment is based on complete surgical resection.The efficacy of systemic radiotherapy and chemotherapy is not clear.

High spindle and kinetochore-associated complex subunit-3 expression predicts poor prognosis and correlates with adverse immune infiltration in hepatocellular carcinoma

BACKGROUND Spindle and kinetochore-associated complex subunit 3(SKA3)is a malignancyassociated gene that plays a critical role in the regulation of chromosome separation and cell division.However,the molecular mechanism through which SKA3 regulates tumor cell proliferation in hepatocellular carcinoma(HCC)has not been fully elucidated.AIM To investigate the molecular mechanisms underlying the role of SKA3 in HCC.METHODS SKA3 expression,clinicopathological,and survival analyses were performed using multiple public database platforms,and the results were verified by Western blot and immunohistochemistry staining using collected clinical samples.Functional enrichment analyses were performed to evaluate the biological functions and molecular mechanisms of SKA3 in HCC.Furthermore,the Tumor Immune Estimation Resource and single-sample Gene Set Enrichment Analysis(ssGSEA)algorithms were utilized to investigate the abundance of tumor-infiltrating immune cells in HCC.The response to chemotherapeutic drugs was evaluated by the R package“pRRophetic”.RESULTS We found that upregulated SKA3 expression was significantly correlated with poor prognosis in patients with HCC.Multivariable Cox regression analysis indicated that SKA3 was an independent risk factor for survival.GSEA revealed that SKA3 expression may facilitate proliferation and migratory processes by regulating the cell cycle and DNA repair.Moreover,patients with high SKA3 expression had significantly decreased ratios of CD8+T cells,natural killer cells,and dendritic cells.Drug sensitivity analysis showed that the high SKA3 group was more sensitive to sorafenib,sunitinib,paclitaxel,doxorubicin,gemcitabine,and vx-680.CONCLUSION High SKA3 expression led to poor prognosis in patients with HCC by enhancing HCC proliferation and repressing immune cell infiltration surrounding HCC.SKA3 may be used as a biomarker for poor prognosis and as a therapeutic target in HCC.