Development of wavelength calibration techniques for high-resolution x-ray imaging crystal spectrometers on the EAST tokamak

Newly developed large-area pixelated two-dimensional detector and two-crystal assemblies were deployed for the first time on tokamaks to enable time-resolved Bragg-diffracted x-ray imaging with good framing rate and water-cooling capabilities for in-vacuum long-pulse operations. High-quality helium-like (He-like) and hydrogen-like (H-like) argon spectra have been observed simultaneously for the first time on a single detector for a wide range of plasma parameters to infer both ion temperature and rotation profiles and support studies on spontaneous rotation, impurity transport, and RF physics. Since tokamak plasmas rotate in both the poloidal (θ) and toroidal (ϕ) directions, a reliable wavelength calibration is needed to account for the correct Doppler shift as well as to compute the spectrometer's instrumental function. Ly_α lines emitted from Cd x-ray tubes are proposed to be used as "markers" to provide an in situ calibration of the EAST's X-ray imaging crystal spectrometer systems measuring He- and H-like argon spectra. The first lab test indicated that the X-ray tube can excite strong Ly_α lines at 15 kV voltage and 1 mA current when the crystal is shined for 10 min. Other indirect calibration methods using locked-mode discharge scenarios were also studied as complementary methods.

Simultaneous measurement of C VI, Ne X, and Li III charge exchange lines on EAST

The core toroidal charge exchange recombination spectroscopy system on experimental advanced superconducting tokamak (EAST) has been enhanced recently to extend the spectral range. The C VI charge exchange line at 529.059 nm, Ne X line at 524.897 nm, and Li III line at 516.67 nm are observed successfully. The measurements were performed by injecting neon gas and dropping lithium powder simultaneously during the 2016 EAST experimental campaign. One channel connected to a neon lamp is used to perform the real-time wavelength calibration on a shot-to-shot basis. The preliminary results indicate that ion temperature profiles from the carbon and neon impurities are in excellent agreement and provide a consistency check of the measurement from different impurities. Toroidal velocity correction associated with the energy-dependent cross section has been performed. Toroidal rotation of neon impurity is obviously faster than C VI across the whole profile. A cumulative and saturated effect of core lithium ions was observed.

Upgrade of X-ray crystal spectrometer for high temperature measurement using neon-like xenon lines on EAST

A two-crystal X-ray spectrometer system has been implemented in the EAST tokamak to simultaneously diagnose high- and low-temperature plasmas using He- and H-like argon spectra. But for future fusion devices like ITER and Chinese Fusion Engineering Test Reactor (CFETR), argon ions become fully stripped in the core and the intensity of the H-like lines will be significantly at high temperatures (T_e > 5 keV). With increasing auxiliary heating power on EAST, the core plasma temperature could also reach 5 keV and higher. In such conditions, the use of a xenon puff becomes an appropriate choice for both ion-temperature and flow-velocity measurements. A new two-crystal system using a quartz 110 crystal (2d = 4.913 Å) to view He-like argon lines and a quartz 011 crystal (2d = 6.686 Å) to view Ne-like xenon spectra has been deployed on a poloidal X-ray crystal spectrometer. While the He-like argon spectra will be used to measure the plasma temperature in the edge plasma region, the Ne-like xenon spectra will be used for measurement in the hot core. The new crystal arrangement allows a wide temperature measurement ranging from 0.5 to 10 keV or even higher, being the first tests for burning plasmas like ITER and CFETR. The preliminary result of lab-tests, Ne-like xenon lines measurement will be presented.

Effect of long-term organic fertilization on the soil pore characteristics of greenhouse vegetable fields converted from rice-wheat rotation fields

The shift from rice-wheat rotation (RWR) to greenhouse vegetable soils has been widely practiced in China. Several studies have discussed the changes in soil properties with land-use changes, but few studies have sought to address the differences in soil pore properties, especially for fields based on long-term organic fertilization under greenhouse vegetable system from RWR fields. This study uses the X-ray computed tomography (CT) scanning and statistical analysis to compare the long-term effects of the conversion of organic greenhouse vegetable fields (over one year, nine years, and fourteen years) from RWR fields on the soil macropore structure as well as the influencing factors from samples obtained in Nanjing, Jiangsu, China, using the surface soil layer and triplicate samples. The results demonstrated that the macropore structure became more complex and stable, with a higher connectivity, fractal dimension (FD) and a lower degree of anisotropy (DA), as the greenhouse vegetable planting time increased. The total topsoil macroporosity increased considerably, but the rate of increase gradually decelerated with time. The transmission pores (round pores ranging from 50 to 500μm) increased with time, but the biopores (>2000μm) clearly decreased after nine years of use as greenhouse vegetable fields. Soil organic matter (OM) has a significant relationship with the soil pore structure characteristics, especially for the transmission pores. In addition, organic fertilization on the topsoil had a short-term effect on the pores, but the effect stabilized and had a weak influence on the pores over longer periods. These results suggested that organic fertilization was conducive for controlling soil degradation regarding it physical quality for water and oxygen availability in the short term.

[Analysis of 833 times measured hepatic venous pressure gradient]

Objective: To summarize and analyze the clinical data of hepatic venous pressure gradient (HVPG) and to explore the application value of HVPG in the diagnosis, evaluation and clinical treatment of portal hypertension in cirrhosis. Methods: The patient data of HVPG measurement performed in Shandong Provincial Hospital from April 2010 to November 2017 were collected. Results: A total of 633 patients with 833 times of HVPG measurements were included. There was significant difference in HVPG between patients with different etiologies, different Child-pugh grades and different degrees of decompensated cirrhosis. Conclusion: The HVPG test is suitable for the diagnosis and evaluation of portal hypertension. The HVPG of patients with different severity of liver cirrhosis can guide the choice of the treatment plan, and the HVPG measurement should also be strictly standardized and quality control.

[Topoisomerase inhibitor upregulates MICA/B expression in breast cancer cells through ATM/ATR and NF-κB pathway]

OBJECTIVE

To investigate the effects of chemotherapeutic agents widely used in clinical practice on major histocompatibility complex class I-related chain A and B (MICA/B) expression in breast cancer cells, and to explore the molecular mechanisms involved.

METHODS

We examined MICA/B mRNA and surface protein expressions in breast cancer cells treated with chemotherapeutic agents by real-time RT-PCR and flow cytometry respectively. The blocking effects of ataxia telangiectasia mutated and Rad3-related kinase (ATM/ATR) inhibitor caffeine and nuclear factor κB (NF-κB) inhibitor pynolidine dithiocarbamate (PDTC) on etoposide-upregulated MICA/B mRNA and surface protein expressions were investigated. Electrophoretic mobility shift assay (EMSA) was taken to investigate whether etoposide enhanced the binding of NF-κB to MICA/B gene promoter.

RESULTS

Three topoisomerase inhibitors etoposide, camptothecin and doxorubicine upregulated MICA and MICB mRNA expressions in breast cancer cell MCF-7. Comparing to no-drug-treated cells, MICA mRNA levels increased to (1.68±0.17), (2.54±0.25) and (3.42±0.15) fold, and levels of MICB mRNA increased to (1.82±0.24), (1.56±0.05) and (5.84±0.57) fold respectively in cancer cells treated by etoposide at the concentrations of 5, 20 and 100 μmol/L (P<0.05). MICA and MICB mRNA levels also increased significantly when MCF-7 cells were incubated with camptothecin or doxorubicine at the specific concentrations (P<0.05). MICB mRNA expression also increased slightly in another breast cancer cell SK-BR-3 treated by topoisomerase II inhibitors etoposide and camptothecin (P<0.05). Furthermore, etoposide and camptothecin upregulated MICA/B surface protein expression in MCF-7 cells (P<0.05), and the upregulation was found in both living and apoptotic cells. Our study showed that etoposide induced-MICA/B expression in MCF-7 was inhibited by caffeine at different concentrations. When cancer cells were treated by caffeine with 1, 5 and 10 mmol/L, MICA mRNA levels decreased from (3.75±0.25) to (0.89±0.05), (0.81±0.02) and (0.48±0.04) fold respectively (P<0.001), and MICB mRNA levels decreased from (6.85±0.35) to (1.36±0.13), (0.76±0.06) and (0.56±0.03) fold (P<0.05), while MICA/B protein levels decreased from (3.42±0.05) to (1.32±0.03), (1.21±0.06) and (1.14±0.03) fold (P<0.001), indicating that etoposide-induced MICA/B expression was inhibited by ATM/ATR inhibitor. Similarly, NF-κB inhibitor PDTC also inhibited MICA/B mRNA and protein expressions induced by etoposide significantly when MCF-7 cells were incubated with PDTC at the concentrations of 10, 50 and 100 μmol/L (P<0.05), indicating that NF-κB was also involved in this process. EMSA showed that the binding of NF-κB to MICA/B promoter enhanced in MCF-7 cells after etoposide treatment.

CONCLUSION

Topoisomerase inhibitor increased MICA/B mRNA and protein expressions in breast cancer cells, indicating that chemotherapeutic agents might increase the recognizing and killing ability of immunocytes to breast cancer cells. ATM/ATR and NF-κB pathways might be involved in it.

MicroRNA-7 inhibits cell proliferation, migration and invasion in human non-small cell lung cancer cells by targeting FAK through ERK/MAPK signaling pathway

OBJECTIVE

To investigate the effects of microRNA-7 (miR-7) on the proliferation, migration and invasion of non-small cell lung cancer NSCLC) cells by targeting FAK through ERK/MAPK signaling pathway.

METHODS

NSCLC tissues and adjacent normal tissues were obtained from 160 NSCLC patients after operation. NSCLC cell lines (A549, H1299 and H1355) and a normal human fetal lung fibroblast cell line (MRC-5) were obtained. NSCLC cells were assigned into miR-7 inhibitors, miR-7 mimics, blank, miR-7 mimics control, miR-7 inhibitors control, FAK siRNA and miR-7 inhibitors + FAK siRNA groups. The expressions of miR-7 and FAK mRNA in tissues and cell lines were detected by qRT-PCR and Western-Blotting. Cell proliferation, migration and invasion were detected by MTT assay, wound scratch assay and Transwell assay.

RESULTS

Compared with adjacent normal tissues, miR-7 expression was down-regulated, but the mRNA and protein expressions of FAK, ERK and MAPK were up-regulated. Compared with the blank and mimics control groups, miR-7 significantly increased but FAK, ERK and MAPK expressions decreased in miR-7 mimics and FAK siRNA groups. Cell proliferation, migration and invasion were inhibited in the miR-7 mimics and FAK siRNA groups, while opposite regarding miR-7 inhibitors group.

CONCLUSION

The miR-7 can inhibit the activation of ERK/MAPK signaling pathway by down-regulating FAK expression, thereby suppressing the proliferation, migration and invasion of NSCLC cells. The miR-7 and its target gene FAK may be novel targets for the diagnosis and treatment of NSCLC.

[Analysis on the epidemiological features of human brucellosis in northern and southern areas of China, 2015-2016]

Different epidemiological features of human brucellosis appeared in both northern and southern areas of China. The disease was seen endemic in the northern and dispersal in the southern provinces. Appropriate strategies for brucellosis prevention and control should be developed, according to the different epidemiological characteristics in the northern or southern areas.

Development of beam emission spectroscopy diagnostic on EAST

Beam Emission Spectroscopy (BES) diagnostic based on Neutron Beam Injection (NBI) on the Experimental Advanced Superconducting Tokamak has been developed. This system consists of 16 × 8 channels which can diagnose the density fluctuation in a rectangular area of about 20 × 10 cm² in the cross section, whose radial position is adjustable from the core to edge just by means of changing the angle of the rotation mirror. The spatial resolution is about 1-3 cm according to the diagnosed radial position. The temporal resolution is 1 μs. Space calibration of the diagnostic system is done based on the reversibility of the optical path. The NBI modulation experiment shows the success of BES development.

[The research progress of CO(2) laser in the treatment of oral lichen planus]

Oral lichen planus (OLP) is a common oral mucosal disease. The etiology of OLP is not clear. The treatment of OLP is difficult as some of the OLP patients have little effects to the conventional mucosal treatments. In recent years, laser therapy has been adopted to treat patients with OLP. The CO(2) laser therapy has drawn much attention of doctors and scholars because of its advantages in treating the OLP. This review article mainly discusses the principle, effects and some state-of-the-art progresses in OLP treatment using CO(2) laser.

[Value of fragmented QRS wave in evaluating the prognosis of patients with coronary artery disease]

Objective: The aim of the current study was to investigate the predictive value of fragmented QRS wave ( fQRS) for the prognosis of patients with coronary heart disease (CHD). Methods: A total of 714 consecutive patients with confirmed CHD were included from Department of Cardiology, General Hospital of PLA between January 2013 and January 2014, and were divided into fQRS group and non-fQRS group based on the presence of fQRS wave or not according to Electrocardiograph (ECG). The baseline, ECG characteristic value, the echocardiography results of the patients were compared between the two groups. Cardiac events were recorded in all patients during 12 months' follow-up. Subgroup analysis was also conducted among patients with abnormal Q wave to investigate the association between fQRS and cardiovascular events. Results: A total of 673 patients completed the follow-up, with 533 in fQRS group and 140 in non-fQRS group. The P wave duration in the fQRS group was longer than non-fQRS group [(92±21) vs (82±23)ms, P<0.01]. The left ventricular ejection fraction (LVEF) value in the fQRS group was lower than non-fQRS group (42%±22% vs 49%±15%, P<0.01) according to echocardiography results. The subgroup analysis with abnormal Q wave showed that compared with non-fQRS group, the left ventricular ejection fraction (LVEF) value in the group of fQRS was lower (38%±21% vs 50%±7%, P<0.01). There was statistically significant in the mortality of patients within follow-up period between the two groups (P<0.05), and the survival time in fQRS group was shorter than the non-fQRS group [(28.3±3.4) vs (30.5±1.5)months, P<0.01]. Conclusion: FQRS presence in body surface ECG of CHD patients with abnormal Q wave is a sign for increased risk of cardiovascular events, which can serve as an indicator to identify CHD patients at high risk of death.

Improved spatial calibration for the CXRS system on EAST

A Charge eXchange Recombination Spectroscopy (CXRS) diagnostic system has been developed to measure profiles of ion temperature and rotation since 2014 on EAST. Several techniques have been developed to improve the spatial calibration of the CXRS diagnostic. The sightline location was obtained by measuring the coordinates of three points on each sightline using an articulated flexible coordinate measuring arm when the vessel was accessible. After vacuum pumping, the effect of pressure change in the vacuum vessel was evaluated by observing the movement of the light spot from back-illuminated sightlines on the first wall using the newly developed articulated inspection arm. In addition, the rotation of the periscope after vacuum pumping was derived by using the Doppler shift of neutral beam emission spectra without magnetic field. Combining these techniques, improved spatial calibration was implemented to provide a complete and accurate description of the EAST CXRS system. Due to the effects of the change of air pressure, a ∼0.4° periscope rotation, yielding a ∼20 mm movement of the major radius of observation positions to the lower field side, was derived. Results of Zeeman splitting of neutral beam emission spectra with magnetic field also showed good agreement with the calibration results.

Measurement of the electron and ion temperatures by the x-ray imaging crystal spectrometer on joint Texas experimental tokamak

An x-ray imaging crystal spectrometer has been developed on joint Texas experimental tokamak for the measurement of electron and ion temperatures from the K_α spectra of helium-like argon and its satellite lines. A two-dimensional multi-wire proportional counter has been applied to detect the spectra. The electron and ion temperatures have been obtained from the Voigt fitting with the spectra of helium-like argon ions. The profiles of electron and ion temperatures show the dependence on electron density in ohmic plasmas.

Measurement of helium-like and hydrogen-like argon spectra using double-crystal X-ray spectrometers on EAST

A two-crystal assembly was deployed on the tangential X-ray crystal spectrometer to measure both helium-like and hydrogen-like spectra on EAST. High-quality helium-like and hydrogen-like spectra were observed simultaneously for the first time on one detector for a wide range of plasma parameters. Profiles of line-integrated core ion temperatures inferred from two spectra were consistent. Since tungsten was adopted as the upper divertor material, one tungsten line (W XLIV at 4.017 Å) on the short-wavelength side of the Lyman-α line (Lα1) was identified for typical USN discharges, which was diffracted by a He-like crystal (2d = 4.913 Å). Another possible Fe XXV line (1.85 Å) was observed to be located on the long-wavelength side of resonance line (w), which was diffracted from a H-like crystal (2d = 4.5622 Å) on the second order. Be-like argon lines were also observable that fill the detector space between the He-like and H-like spectra.

First measurement of the edge charge exchange recombination spectroscopy on EAST tokamak

An edge toroidal charge exchange recombination spectroscopy (eCXRS) diagnostic, based on a heating neutral beam injection (NBI), has been deployed recently on the Experimental Advanced Superconducting Tokamak (EAST). The eCXRS, which aims to measure the plasma ion temperature and toroidal rotation velocity in the edge region simultaneously, is a complement to the exiting core CXRS (cCXRS). Two rows with 32 fiber channels each cover a radial range from ∼2.15 m to ∼2.32 m with a high spatial resolution of ∼5-7 mm. Charge exchange emission of Carbon VI CVI at 529.059 nm induced by the NBI is routinely observed, but can be tuned to any interested wavelength in the spectral range from 400 to 700 nm. Double-slit fiber bundles increase the number of channels, the fibers viewing the same radial position are binned on the CCD detector to improve the signal-to-noise ratio, enabling shorter exposure time down to 5 ms. One channel is connected to a neon lamp, which provides the real-time wavelength calibration on a shot-to-shot basis. In this paper, an overview of the eCXRS diagnostic on EAST is presented and the first results from the 2015 experimental campaign will be shown. Good agreements in ion temperature and toroidal rotation are obtained between the eCXRS and cCXRS systems.

[A ten-year clinical study of cracked teeth restored with glass ceramic crowns]

Objective: To evaluate the clinic performance of high strength glass ceramic crowns for the painful cracked teeth during a 10-year observation period. Methods: Forty-two posterior teeth from 36 patients were diagnosed as having a crack, biting painful and sensitivity to cold were selected in the Department of Prosthodontic, Institute and Hospital of Stomatology, Nanjing University Medical School. The lost-wax hot pressed glass ceramic crowns were bonded on the minimally invasive prepared teeth by modern adhesive technology. Patients were interviewed and went through clinic examination after one week, one month, and every six months. Results: The effectiveness of 42 glass ceramic crowns for cracked teeth was evaluated for a mean observation time over 10-year. At the first week, 29(81%) patients were free of pain, three still had sensitivity to cold and chewing pain, three still had sensitivity to cold, one had painful to cold and hot. After one month, two patients still had chewing pain, and one tooth needed endodontic treatment after six months. In 10 years, 2(5%) all ceramic crowns were broken, the other 40 restorations kept good clinical performances with a 10-year survival rate of 95%. Conclusions: The high strength glass ceramic crowns are very effective and successful in treating the cracked teeth and then keep the good mastication function and appearance.

[Prediction value of deceleration capacity of rate and GRACE risk score on major adverse cardiac events in patients with acute myocardial infarction]

OBJECTIVE

To investigate the prediction value of deceleration capacity of rate (DC) and GRACE risk score for cardiovascular events in AMI patients.

METHODS

Consecutive AMI patients with sinus rhythm hospitalized in our department during August 2012 to August 2013 were included in this prospective study. 24-hour ECG Holter monitoring was performed within 1 week, and the DC value was analyzed, GRACE risk score was acquired with the application of GRACE risk score calculator. Patients were followed up for more than 1 year and major adverse cardiac events (MACE) were obtained. Analysised the Kaplan Meier survival according to DC and GRACE score risk stratification respectively.

RESULTS

A total of 157 patients were enrolled in the study (average age: (58.9±12.7)years old). The average follow-up was (20.54±2.85) months. Mortality during follow-up was significantly higher in patients with DC>2.5 compared to patients with DC≤2.5 (P<0.01). In terms of early warning cardiac death, the area under ROC curve of DC risk stratification was 0.898 (95%CI 0.840-0.940, P<0.01), the sensitivity was 84.6%, and the specificity was 84.0%. The area under ROC curve of GRACE risk stratification was 0.786 (95%CI 0.714-0.847, P<0.01), the sensitivity was 84.6%, and the specificity was 74.3%. In terms of early warning cardiac adverse events, the ROC curve of DC was 0.747(95%CI 0.672-0.813, P<0.01), with the 90.0% sensitivity and 67.7% specificity. The GRACE risk stratification was 0.708 (95%CI 0.652-0.769, P<0.01), with the 63.3% sensitivity and 75.6% specificity. Subgroup analysis showed that mortality during follow-up was significantly higher in high risk patients than those with intermediate and low risk patients according to DC risk stratification in intermediate and low risk patients by GRACE risk stratification (P<0.01).

CONCLUSION

DC could predict cardiac death and MACE in patients with AMI. DC risk stratification is superior to GRACE risk score on outcome assessment in this AMI patient cohort.

[Cross-sectional study of differential effects with age on non-invasive central hemodynamics and peripheral arterial stiffness of healthy people in Beijing communities]

OBJECTIVE

To observe the variation of central hemodynamics and peripheral arterial stiffness in different ages and to investigate the parameters of differential effects in younger individuals (≤60y) and older individuals (>60y).

METHODS

We conducted a population-based cross-sectional study in eight regions by random cluster sampling, from April to July 2014 in Beijing, China.Central hemodynamics and peripheral arterial stiffness parameters were determined in 861 healthy (372 male), normotensive individuals, aged 20 to 91(56±14) years.The main observed indexes were central systolic blood pressure (cSBP), arterial augmentation index (AI), augmentation pressure (AP), heart-ankle pulse wave velocity (haPWV) and brachial-ankle PWV (baPWV). Subjects were divided into six groups by 10 aged segment.Differences between groups and age tendency were observed.

RESULTS

The mean values of cSBP, AI, AP, haPWV and baPWV were (113±12) mmHg, (90±18)%, (-5±9) mmHg, (987±144) cm/s and (1 382±254) cm/s, respectively.cSBP, AI, AP, haPWV and baPWV increased with age (P<0.001). In average, cSBP, baPWV and haPWV increased 3 mmHg, 97 cm/s and 62 cm/s by additional 10 years, respectively.cSBP, AI and AP increased slowly after 60 years old, while haPWV and baPWV increased significantly with age (P<0.001). Stepwise regression analysis showed: cSBP was mainly relevant with mean arterial pressure(b=0.990, P<0.001), while baPWV and haPWV were relevant with age(b=8.858, 5.971; P<0.001). AI and AP were associated with height and rest heart rate (b=-0.676, -0.660 and b=-0.361, -0.341, P<0.001). Individuals were divided into two groups by age 60.The age-related changes in AI were significant in under 60-year-old; while the changes in baPWV were more prominent in over 60-year-old.However there was no significant difference in cSBP between two groups.

CONCLUSIONS

In healthy people, there are obvious differences of age tendency in central hemodynamics and peripheral arterial stiffness parameters.AI might be a good predictor of cardiovascular disease for early stage, especially for early coronary artery disease.

BMP6 and BMP4 expression in patients with cancer-related anemia and its relationship with hepcidin and s-HJV

In the present study, we investigated BMP6 and BMP4 expression in patients with cancer-related anemia (CRA) as well as its relationship with hepcidin and s-HJV. The avidin-biotin system enzyme-linked immunosorbent assay was used to test serum levels of BMP6, BMP4, s-HJV, and hepcidin in 53 cancer patients with anemia and 52 control cancer patients without anemia. Serum levels of BMP6 and hepcidin in the anemia group were 434.53 ± 212.11 ng/mL and 5.68 ± 3.89 μg/L, respectively. In the non-anemia cancer group, serum BMP6 and hepcidin levels were 334.37 ± 171.32 ng/mL and 4.60 ± 2.28 μg/L, which were significantly lower than the levels for the CRA group (P < 0.05). In addition, the serum level of s-HJV was 0.69 ± 0.28 ng/mL in the CRA group, which was significantly lower compared to that for the non-anemia group (1.07 ± 1.00 ng/mL, P < 0.01). There were no significant differences in BMP4 expression between the two groups. BMP6 was negatively correlated with s-HJV and Hb (r = -0.2536 and -0.2949, P < 0.01), but was not correlated with hepcidin. Similarly, BMP4 expression was not correlated with Hb, s-HJV, or hepcidin. Our study shows that patients with CRA had high expression of BMP6 and hepcidin and low expression of s-HJV. BMP6 was found to be negatively correlated with s-HJV; both regulate hepcidin expression and play important roles in the development of anemia.

Distribution of LIM domain kinase 1 in the olfactory bulb, cerebral cortex, hippocampus, and cerebellum of the App/PS+/- mice

LIM domain kinase 1 (LIMK1), an actin-binding kinase, can phosphorylate and inactivate its substrates, and can regulate long-term memory and synaptic plasticity. Both β-amyloid precursor protein (App) and presenilin (PS) are functional degeneration factors during early neuronal development, and are considered as potential factors that contribute to the development of Alzheimer's disease (AD). However, hardly any information is available about the distribution and expression of LIMK1. Thus, using the App and PS deficient mice, the role of LIMK1 was demonstrated in the absence of App and PS. Our results showed that LIMK1 was present in the nerve fiber layer and external plexiform layer of the olfactory bulb, as well as in the mitral cells and Purkinje cells of the cerebellum in App and PS deficient mice. Additionally, LIMK1 was concentrated in the granule cell layer of the olfactory bulb and cerebellum and LIMK1 positive cells were located in the CA1 region of the hippocampus. Our study indicates that there is a connection between LIMK1 and AD in the mouse model of AD. This might explain neurological problems such as cerebellar ataxia, impaired long-term memory, and impaired synaptic plasticity observed in AD.

Promotion of exocyclic bond cleavages in the decomposition of 1,3-disilacyclobutane in the presence of a metal filament

The primary decomposition of 1,3-disilacyclobutane (DSCB) on a tungsten filament and its secondary gas-phase reactions in a hot-wire chemical vapor deposition (CVD) reactor have been studied using laser ionization mass spectrometry. Under the collision-free conditions, DSCB decomposes on the W filament to produce H2 molecules with an activation energy of 43.6 ± 4.1 kJ·mol(-1). With the help of the isotope labeling and chemical trapping methods, the mechanistic details in the secondary gas-phase reactions important in the hot-wire CVD reactor setup have been examined. The dominant pathway has been demonstrated to be the insertion of the cyclic 1,3-disilacyclobut-1-ylidene, generated by exocyclic Si-H bond rupture, into the Si-H bond in DSCB to form 1,1'-bis(1,3-disilacyclobutane) (174 amu). The successful trapping of 1,3-disilacyclobut-1-ylidene by both 1,3-butadiene and trimethylsilane provides compelling evidence for the existence of this cyclic silylene species in the hot-wire CVD reactor with DSCB. Other reactions operating in the reactor include the DSCB cycloreversion to form silene and the ring opening of DSCB via 1,2-H shift to produce silene/methylsilylene and 1-methylsilene/silylene. The introduction of an additional Si atom in the four-membered ring monosilacyclobutane molecule has caused two major changes in the reaction chemistry assumed by DSCB: (1) The endocyclic cycloreversion reactions that dominate in the decomposition of monosilacyclobutane molecules only play a much less important role in the dissociation of DSCB; and (2) the exocyclic bond cleavages are promoted in DSCB due to the ring stabilization caused by the introduction of one additional Si atom.

Upgrades of imaging x-ray crystal spectrometers for high-resolution and high-temperature plasma diagnostics on EAST

Upgrade of the imaging X-ray crystal spectrometers continues in order to fulfill the high-performance diagnostics requirements on EAST. For the tangential spectrometer, a new large pixelated two-dimensional detector was deployed on tokamaks for time-resolved X-ray imaging. This vacuum-compatible detector has an area of 83.8 × 325.3 mm(2), a framing rate over 150 Hz, and water-cooling capability for long-pulse discharges. To effectively extend the temperature limit, a double-crystal assembly was designed to replace the previous single crystals for He-like argon line measurement. The tangential spectrometer employed two crystal slices attached to a common substrate and part of He- and H-like Ar spectra could be recorded on the same detector when crystals were chosen to have similar Bragg angles. This setup cannot only extend the measurable Te up to 10 keV in the core region, but also extend the spatial coverage since He-like argon ions will be present in the outer plasma region. Similarly, crystal slices for He-like iron and argon spectra were adopted on the poloidal spectrometer. Wavelength calibration for absolute rotation velocity measurement will be studied using cadmium characteristic L-shell X-ray lines excited by plasma radiation. A Cd foil is placed before the crystal and can be inserted and retracted for in situ wavelength calibration. The Geant4 code was used to estimate X-ray fluorescence yield and optimize the thickness of the foil.

Wavelength calibration of x-ray imaging crystal spectrometer on Joint Texas Experimental Tokamak

The wavelength calibration of x-ray imaging crystal spectrometer is a key issue for the measurements of plasma rotation. For the lack of available standard radiation source near 3.95 Å and there is no other diagnostics to measure the core rotation for inter-calibration, an indirect method by using tokamak plasma itself has been applied on joint Texas experimental tokamak. It is found that the core toroidal rotation velocity is not zero during locked mode phase. This is consistent with the observation of small oscillations on soft x-ray signals and electron cyclotron emission during locked-mode phase.

Development of the charge exchange recombination spectroscopy and the beam emission spectroscopy on the EAST tokamak

Charge eXchange Recombination Spectroscopy (CXRS) and Beam Emission Spectroscopy (BES) diagnostics based on a heating neutral beam have recently been installed on EAST to provide local measurements of ion temperature, velocity, and density. The system design features common light collection optics for CXRS and BES, background channels for the toroidal views, multi-chord viewing sightlines, and high throughput lens-based spectrometers with good signal to noise ratio for high time resolution measurements. Additionally, two spectrometers each has a tunable grating to observe any wavelength of interest are used for the CXRS and one utilizes a fixed-wavelength grating to achieve higher diffraction efficiency for the BES system. A real-time wavelength correction is implemented to achieve a high-accuracy wavelength calibration. Alignment and calibration are performed. Initial performance test results are presented.

Preparations for the motional Stark effect diagnostic on EAST

Measurement and control of the current profile is essential for high performance and steady state operation of Experimental Advanced Superconducting Tokamak (EAST). For this purpose, a conventional Motional Stark Effect (MSE) diagnostics utilizing photoelastic modulators is proposed and investigated. The pilot experiment includes one channel to verify the feasibility of MSE, whose sightline intersects with Neutral Beam Injection at major radius of R = 2.12 m. A beam splitter is adopted for simultaneous measurements of Stark multiplets and their polarization directions. A simplified simulation code was also developed to explore the Stark splitting spectra. Finally, the filter is optimized based on the viewing geometry and neutral beam parameters.