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After studying the principle of ion water atomization, an intelligent humidification system of ion water atomization was designed. The system sensed the external temperature and humidity through the sensor, and built-in intelligent chip to calculate the sensor data. Automatically adjust the amount of ionized water atomization to maintain environmental humidity; Ions can also be added in the atomization humidification process can effectively inhibit the growth of bacteria and eliminate pathogens, this technology has a good practical and practical value.

We experimentally demonstrate a novel optical fiber chemosensor for trace Cu2+ ions detection that is implemented by using an in-line optical fiber Mach–Zehnder interferometer (MZI) in conjunction with an optoelectronic oscillator (OEO). The MZI is fabricated by lateral offset splicing a section of D-shaped fiber between two single-mode fibers. It splices the broadband optical source into a sinusoidal-shaped light, which can form a single passband microwave photonic filter (MPF) by combining the Mach–Zehnder modulator, a segment of fiber and a photodetector. The center frequency of the MPF, determined by the free spectra range of MZI, is affected by the solution concentration. Incorporating the MPF in the OEO sensor, the oscillation frequency is determined by the solution concentration. Therefore, we can estimate the solution concentration by measuring the microwave frequency change. We carry out a proof to concept experiment. High sensitivity Cu2+ ions concentration sensing with sensitivity of 13 Hz/(μM/L) is achieved. The maximum measurement error of concentration obtained is within 1.38 μM/L. The proposed sensor has merits of high interrogation speed, simple operation, high sensitivity and accuracy, offering the potentials in a wide range of biological application scenarios.

This retrospective report, detailed the volunteer work of the radiology department in Wuhan Leishenshan Hospital at the COVID-19 epidemic period. Under the background of the lack of medical staff

Visual interfaces and wireless monitoring have played significant roles in the application of electromagnetic transmitters. Therefore, we have designed a wireless monitoring system that is based on the Visual Studio 2015 Windows form application by using C# language and multi-threading technology. The system can effectively implement many functions, including time monitoring via a real-time clock, switching of the transmitting frequency, changing of transmission mode, and the storage and verification of the transmitter condition information. These things allow the wireless monitoring system to support condition monitoring and operation control of the transmitter. The results of several field tests confirm that the proposed wireless monitoring system provides a user-friendly interface and convenient and stable operation. The system is able to satisfy the wireless monitoring and multifunctional demands for transmitters implemented in land electromagnetic exploration and act as a reference for scientific researchers pursuing instrument development and electromagnetic prospecting.

Objective: We aimed to evaluate the quantitative parameters of CT scans performed on pregnant women with COVID-19 who had different reverse transcription-polymerase chain reaction (RT-PCR) results.Methods: Pregnant women with suspected cases of COVID-19 pneumonia (confirmed by next-generation sequencing or RT-PCR) who underwent high-resolution lung CT scans were retrospectively enrolled. Patients were grouped based on the results of the RT-PCR and the first CT scan: group 1 (double positive patients; positive RT-PCR and CT scan) and group 2 (negative RT-PCR and positive CT scan). The imaging features and their distributions were extracted and compared between the two groups.Results: Seventy-eight patients were admitted to the hospital between Dec 20, 2019, and Feb 29, 2020. The mean age of the patients was 31.82 years (SD 4.1, ranged from 21 to 46 years). The cohort included 14 (17.95%) patients with a positive RT-PCR test and 64 (82.05%) with a negative RT-PCR test, there were 37 (47.44%) patients with a positive CT scan, and 41 (52.56%) patients with a negative CT scan. The sensitivity, specificity, positive predictive value, negative predictive value and accuracy of CT-based diagnosis of COVID-19 were 85.71%, 60.94%, 32.40%, 95.12% and 65.38%, respectively. COVID-19 pneumonia mainly involved the right lower lobe of the lung. There were 53 semi-quantitative and 59 quantitative parameters, which were compared between the two groups. There were no significant differences in the quantitative parameters. However, the Hellinger distance was significantly different between the two groups, albeit with a limited diagnostic value (AUC=0.63).Conclusions: Pregnant women with pneumonia usually present with typical abnormal signs on CT. Although multidimensional CT quantitative parameters are somewhat different between groups of patients with different RT-PCR results, it is still impossible to accurately predict whether the RT-PCR will be positive, which would allow for the earlier detection of SARS-CoV-2 infection.

This chapter describes the clinical symptoms and signs of AECHB and HBV ACLF, classification, grading of HBV ACLF and their features, diagnostic principles and standards in liver pathology, biochemistry, and virology of HBV ACLF. 1. Liver failure is defined as serious damage to the liver cause by a variety of etiologies, leading to liver function disorder or even decompensation, and clinical syndromes with coagulopathy, jaundice, hepatic encephalopathy, and ascites. 2. Severe hepatitis B can be indicated pathologically by apparent hepatocellular necrosis, including extensive multifocal, confluent, bridging, sub-massive or massive necrosis. 3. Laboratory tests during the course of severe exacerbation of chronic hepatitis B can reflect pathological changes and liver function in a timely manner, providing objective and informative reference data for evaluation of disease severity and treatment efficacy. Among the most important laboratory tests are those for prothrombin activity, international normalized ratio, and increases in total bilirubin concentration. 4. Severe hepatitis B is associated with interactions between the virus and host factors. Detection of HBV DNA, HBV genotype, quasispecies and HBV mutation can provide important theoretical bases for the prevention, control or mitigation of the progress of severe hepatitis B. 5. Noninvasive imaging modalities can be used to visualize the entire liver and parts of it. Measuring liver volume to evaluate liver size and liver reserve capacity is regarded as important in diagnosis, surgical approach and prognostic evaluation of patients with severe exacerbation of chronic hepatitis B and liver failure. 6. Model for End-Stage Liver Disease (MELD) is the first quantitative method developed to assess whether a patient with liver failure requires a liver transplant. The predictive value of the MELD model has been improved by the MELD-Na, iMELD, and MESO models. Several other valuable prognostic models have been developed. For example, for patients with HBV-ACLF, the established TPPM scoring system was found to be more predictive than MELD score.

Marine Controlled-Source Electromagnetic (MCSEM) methods have been recognized as an important and effective tool in accurate analysis of shallow electrically resistive structures such as oil, gas and gas hydrate. However, the MCSEM performance in the deep ocean is strongly affected by the hardware design, especially the transmitter system. We have developed a series of deep-towed MCSEM transmitter systems. The design of the transmitter system meets serious challenges such as long-distance and high-voltage transmission, water sealing under high-pressure, the real-time monitoring of seafloor status information 4 km below the sea-surface. In this paper, we present the latest research and development of the MCSEM transmitter systems by presenting key technologies in hardware development and implementation details. The deep tow transmitter system consists of three parts: the deck unit, the deep tow cable and the deep tow unit, which can transmit the high frequency and high power to the seawater, maintaining a high-speed data communication with control center which in the ship’s lab. We conducted several experiments in the South China Sea from August of 2010, to November of 2019. The results showed that the development of the transmitter is successful and it can be used for oil, gas and gas hydrate exploration as an effective source.

European Commission (EU) is one of largest developed economic region in the world. It was established in 1958 and expanded to include 28 countries in 2017. A three- tiers product safety system was established and required all member countries to implement with the example of toy product. This paper explained the legal system of EU, differences of the directives and regulations and harmonized standards..

A novel design of pole mounted switch controller is introduced in this paper, embedded Linux operating system was used to enrich the functions of the pole mounted controller and to enhance the intelligence of the controller. Software structure of this novel designed controller is presented in detail. Multiple processes design method was applied to split the software application into 3 processes, namely user interface, communication and fault treatment. Socket communication was re-designed and a shared memory method was adopted to realize interprocess communication.

Phosphorescent materials are crucial to improve the luminescence and efficiency of organic light emitting diodes (OLED), because its internal quantum efficiency can reach 100%. So the studying of optical and electrical properties of phosphorescent materials is propitious for the further development of phosphorescent OLED. Phosphorescent materials were generally doped into different host materials as emitting components, not only played an important role in emitting light but also had a profound influence on carrier transport properties. We studied the optical and electrical properties of the blue 4,4′-bis(2,2-diphenylvinyl)-1,1′-biphenyl (DPVBi)-based devices, adding a common yellow phosphorescent material bis[2-(4-tert-butylphenyl)benzothiazolato-N,C2′] iridium(acetylacetonate) [(t-bt)2Ir(acac)] in different positions. The results showed (t-bt)2Ir(acac) has remarkable hole-trapping ability. Especially the ultrathin structure device, compared to the device without (t-bt)2Ir(acac), had increased the luminance by about 60%, and the efficiency by about 97%. Then introduced thin 4,4′-bis(carbazol-9-yl)biphenyl (CBP) host layer between DPVBi and (t-bt)2Ir(acac), and got devices with stable white color.

We have developed a practical conditioning regimen without anti-thymocyte globulin (ATG), irradiation, or other myeloablative alkylating agent for low-income countries in which patients with severe aplastic anemia (SAA), who usually have heavily transfused and a prolonged disease history. The application of ATG, Busulphan, and/or irradiation to cyclophosphamide (Cy) to avoid graft rejection has many short- and long-term complications. In this study, we focused on evaluating a fludarabine-based conditioning regimen, among 83 patients with SAA. Patients were treated with fludarabine (40 mg/m(2) /d; day [-5 to -2]) and cyclophosphamide (50 mg/kg/d; day [-5 to -2]). Altogether, 81 patients indicated initial engraftment, whereas two cases showed primary graft failure. And four of the 81 cases indicated graft rejection during follow-up. Regardless of a high cumulative incidence of acute (55/83; 66.2% grade II-IV; 47/83; 56.6% III-IV) and chronic graft-versus-host disease (50/83; 60.2%), in total, 77 patients showed durable engraftment and transfusion independence, and 64 are alive at a median time of 49 months with an overall survival rate of 66%. In conclusion, this conditioning indicated well toleration, mild toxicity, durable engraftment, excellent survival as well as less cost. Its application might shed new light on SAA at high risk of graft rejection in resource-limited countries.

As product design has entered the stage of green design, virtual design becomes increasingly important, and cutting research is the core of it. This paper established a basic virtual cutting system and the grid models of virtual objects based on PHANTOM Omni hap tic feedback device and its system development toolkit and built up oriented bounding box and operated bounding box collision detection. On the base of these, the paper also presented a new method of cutting force condition judgment of cutting tool, and gave the cutting path planning and grid model reconstruction on the basis of virtual cutting methods of triangular grid unit model. At last, the paper researched the virtual cutting of grid model using computer programming language, providing design methods for product design. The relative methods may advance the effect of product design drastically.

A novel in-line Fabry-Pe´rot interferometer is directly fabricated in a single mode fiber by the use of femtosecond lasers. The spectrum fringe of this interferometer has the visibility of ~5 dB due to the rough and slopped cavity surfaces, making it more difficult for post signal processing and reducing the measurement accuracy and reliability. By choosing the optimal parameters, improving machining environments and methods, ideal Fabry-Pe´rot cavities are fabricated, which are so smooth and parallel that the fringe visibility is as high as ~18 dB. In addition, with an accessible cavity and all-fiber structure, this sensor can work in high temperatures up to 800°C, which is attractive for sensing applications in harsh environments.

Sliding in a dam foundation along potential sliding paths is generally caused by two kinds of external factors: one is the overloading of the designed upstream hydrostatic load due to flooding; and the other is the gradual degradation of the shear strength of joints due to seepage, deformation, damage, and geochemical reactions between water and joint surface minerals. Based on the conceptualized geomechanical model of the Three-Gorges Dam, described in the Part I paper, in this Part II paper the limit equilibrium method and finite element method are used to study the effects of gradual degradation of the shear strength of joints on the stability of the dam foundation. The numerical modeling focuses on the stability conditions of the no. 3 powerhouse-dam section which are estimated to be the most critical. The constraint influences from the adjacent no. 2 and no. 4 powerhouse-dam sections are also included. The failure mechanisms, factors of safety and critical displacements of these dam sections are derived numerically as the measures for stability evaluation. The factor of safety is defined as the ratio between the combined shear strength of joints and intact rock bridges, and the mean shear stress along potential sliding path required for limit equilibrium under the designed external loads. All the results obtained from these different numerical models, together with the results of physical model tests as presented in Part I, are compared in this paper. The comparisons show that both the numerical modeling and physical modeling results support each other and demonstrate the stability of the Three-Gorges Dam foundation as designed. Nevertheless, considering the overall engineering and social–economical importance of the Three-Gorges Dam complex, some additional treatment and reinforcement measures are recommended in this paper.

Background Improvement of current GVHD prophylactic therapies remains an important goal in the allo-HSCT. We have described a novel prophylaxis regimen in a single institution trial. The Chinese Bone Marrow Transplant Cooperative Group (CBMTCG) initiated a phase II multicenter study. Methods The study was designed as a prospective, single arm phase II open-label, multicenter clinical trial. The primary endpoint was improvement of aGVHD by 25% over historical control (40%) in Chinese patients. 508 patients were enrolled. All of the patients received cyclosporine A (CsA), methotrexate (MTX) and mycophenolate mofetil (MMF) (0.5-1.0 g daily for 30 days) as GVHD prophylaxis regimen. Results The primary endpoint was met with cumulative incidences of grades 2 to 4 and grades 3 to 4 aGVHD of 23.2% and 10.3%, respectively. Incidence for cGVHD was 67.4%. The non-relapse mortality (NRM) rate was 18.4% at 2 years. The probabilities of leukemia free survival (LFS) for non-advanced stage and advanced stage patients at 2 years were 69.7% and 44.8% respectively (p = 0.000). Recipient age ≥ 40 years, advanced stage and Busulfan-Fludarabine(BuFlu) conditioning regimen were identified as major risk factors for aGVHD. Recipient age ≥ 40 years, BuFlu conditioning regimens, female donor/male recipient and prior aGVHD were associated with cGVHD. Despite lower RM (relapse mortality), patients with grade 2–4 aGVHD had higher NRM and worse OS and LFS compared to patients with grade 0–1 aGVHD. In contrast, patients with cGVHD had better OS and LFS and lower RM compared to patients without cGVHD. Conclusion The novel GVHD regimen decreased the risk for aGVHD by 42% without improving the risk for cGVHD compared to historical controls. Development of aGVHD was associated with worse OS and LFS as well as higher NRM. In contrast, cGVHD was associated with improved OS and LFS likely attributed to a GVL effect.

Magnetotelluric takes natural electromagnetic as field source to study the earth interior electrical structures. The observations are easy to be interfered by power line interference, so this paper designed a convenience and effective notch filter which could eliminate all of the high-order harmonics within the sampling rate. The notch filter was achieved by interpolation for band-stop filter and different interpolation could meet different trap frequency. After finishing the target notch filter, a series of simulation experiment and the practical test were conducted and the results shown that this notch filter could remove the power line interference effectively and could greatly improve the signal to noise ratio.

A theory is proposed for solving second-harmonic generation accompanying nonlinear reflection of shear (SH) waves. An analysis is presented for the resonant second-harmonic generation in a layered structure consisting of an isotropic layer and two semi-infinite isotropic solids. The result reveals that the effect of second-harmonic cumulative growth will occur once the component of incident SH-wave vector along the boundary equals the magnitude of the longitudinal wave vector of the elastic medium of the solid layer. Moreover, we have formally obtained the analytical expressions for the resonant second-harmonic generation in each region of the layered structure which yields physical insight into the process of the second-harmonic generation not previously available.

There has been considerable development of seismic detectors over the last 80 years. However, there is still a need to further develop new earthquake exploration and data acquisition systems with high precision. In particular, for China to keep up with the latest technology of these systems, it is important to be involved in the research and development, instead of importing systems that soon fall behind the latest technology. In this study, the features of system-on-a-programmable-chip (SoPC) technology are analyzed and used to design a new digital seismic-data acquisition station. The hardware circuit of the station was developed, and the analog board and the main control data-transmission board were designed according to the needs of digital seismic-data acquisition stations. High-definition analog-to-digital converter sequential digital filter technology of the station (cascade integrator comb filter, finite impulse response digital filter) were incorporated to provide advantages to the acquisition station, such as high definition, large dynamic scope, and low noise. A specific data-transmission protocol was designed for the station, which ensured a transmission speed of 16 Mbps along a 55-m wire with low power consumption. Synchronic acquisition was researched and developed, so as to achieve accuracy better than 200 ns. The key technologies were integrated into the SoPC of the main control data-transmission board, so as to ensure high-resolution acquisition of the station, while improving the accuracy of the synchronic acquisition and data-transmission speed, lowering the power consumption, and preparing for the follow-up efforts to tape out.

The knowledge is the source of the competitive advantage and knowledge creation in knowledge-based economy. However, the knowledge transfer is directly under the control of the transfer will and the ability of the knowledge individual. Therefore, if the organizations want to carry out effectively the knowledge transfer, they have to make out the effective incentive mechanism and measures. If they want to make out the effectively motivation measures, they have to identify the relevant factors and their mutual function in the knowledge transfer firstly. Based on above, the paper firstly put forward the necessity of the motivation conduction in the knowledge transfer. Secondly, the paper pointed out the definition and the relevant hypothesies of the motivation conduction in the organizational knowledge transfer. Thirdly, the paper designed the relevant statistic variables of the motivation conduction in the knowledge transfer. Fourthly, the paper carried out the questionnaire investigation amd the statistic analysis on the motivation conduction in the knowledge transfer. Finally, the paper concluded the empirial research and got the relevant conclusions of the motivation conduction.

This paper uses GM method to estimate fix efficient spatial panel data model. The estimating tactic is a three-step approach, by which this paper gets a consistent efficient estimator. This paper also simulates the estimator by use of Monte Carlo.

Using the existing pits, wells and tunnels in mine areas, high power electromagnetic transmitters on the ground and underground (pit, well) and receivers on the ground can be integrated as a quasi 3-D measuring device, which provides a new method for exploration of metal mines. Under-research transmitters as actuating devices can automatically transmit high power inverted square wave in sweep frequency ranging from 0.9375Hz to 9600Hz. Maximum transmitting voltage is 700V and supply current is 60A. At the same time, GPS clock and Real-Time Clock (RTC) can be used to ensure transmitting predefined or user-defined power supply frequency at fixed time and on time. Bluetooth and serial communication interfaces can be used to control transmission and running and edit control parameters. Many kinds of information about auxiliary status can be observed. Reliable, smooth and high-efficient performance of instruments, which has been proved by tests, can fully meet the requirements of electromagnetic exploration of metal mines and replacing materials ‘tap deeply and explore the blind’ of crisis mines.

High voltage square impulses from converter can make stator insulation of inverter-fed motors damaged much earlier. There are many differences in insulation aging mechanism between under continuous impulses and under sine waves. In order to test insulation properties under continuous impulses, a new insulation aging test system is used to simulate the aging effect of converter on the winding insulation in the inverter-fed motors. The influences of impulse amplitude, frequency, on insulation lifetime are investigated by using polyimide film. Finally, an insulation electrical aging lifetime model is developed based on the test results.

In order to reduce the impact of harmonic and negative sequence on the power system, in traction substation can use Scott wiring traction transformer. By using MATLAB to establish a Scott wiring transformer model, the 110 kV side of the three-phase harmonic voltage and current with its harmonic content and negative sequence can be simulated. Comparing simulated results and actual data of one transformer substation, the correctness and accuracy is verified. Finally analyze the two situation of traction network with symmetrical or asymmetrical load. The results showed that adopting Scott wiring transformer in the traction transformer substation is one effective method. Electric railway should be running with the symmetric load as far as possible. So can greatly reduce the harm caused by asymmetric running of the transformer and effectively reduce the impact on power quality.

This paper proposes a novel method for insulation fault detection of power transformer using the genetic programming (GP) method. Fault detection can be seen as a problem of multi-class classification. GP is a way of automatically constructing computer programs using a process analogous to biological evolution. GP methods of problem solving have a great advantage in their power to represent solutions to complex classification problems. The flexibility of representation gives GP the capacity to represent classification problems with means unavailable to other techniques such as neural networks. A binary tree (Bi-tree) structure is presented to transfer an N-class problem into N-1 two-class problems. The proposed method has been tested on the actual records and compared with the conventional methods, fuzzy system method and artificial neural network method. The result shows that GP has advantages over the existing diagnosis methods and provides a new way to solve the problem of fault detection.

In this article we have studied resonant second-harmonic generation accompanying nonlinear Love-wave propagation in an isotropic waveguide consisting of a solid layer and a semi-infinite solid. Generally, the amplitude of the second harmonic arising from the self-interaction of shear wave is independent of propagation distance, i.e., there is no effect of cumulative growth. However, for Love-wave propagation case, there are two shear partial waves in the solid layer deposited on the semi-infinite solid, and the cross-interaction between two shear waves may cause the "resonance" of the driving second harmonic once the phase velocity of the Love-wave equals the longitudinal velocity of the solid layer. Through second-harmonic boundary conditions and initial conditions of excitation, we formally obtain the analytical expressions for the case of resonant second-harmonic generation. The present analysis yields clearly physical insight into the process of resonant second-harmonic generation accompanying nonlinear Love-wave propagation not previously available.

This paper describes a wavelet artificial neural network (ANN) for signal classification, and applies it for transformer Fault Detection with dissolved gas analysis (DGA). The weights of the network are replaced by wavelet functions and are corrected by conjugate gradient method in the training iteration. Preliminary simulation results show wavelet ANN for DGA can get a 95% correct diagnosis rate, superior then BP ANN. Besides, precondition techniques of input data is studied, a suitable precondition algorithm play an important role in ANN.

According to the status that the improved measurement system of loose coal thermal conductivity had more device error sources, which were not conducive to ensured test accuracy, the influence of system hardware error, coal sample self-oxidation exothermic, data processing error and other factors on test accuracy of the thermal conductivity were comprehensively analysed, and then corresponding control measures were raised. The experimental results showed that the system hardware error could be controlled effectively by selecting high-quality test component and controlling heating component size, and the coal self-oxidation exothermic impact can be negligible. The improved measurement system reduced simplified degree of the mathematical model, and solved it through numerical solution, through which can eliminated influence of data processing error effectively.

To clarify the anatomy of the peritoneal reflections of the left perihepatic region, the authors examined 95 cadavers. Thirty-eight were studied radiographically, 37 with sagittal dissection, and 20 with transverse dissection. In over 80% of the cadavers, the left triangular ligament of the liver separated the left suprahepatic space into anterior and posterior sections. The lesser omentum extended to the diaphragm, where its anterior layer reflected and continued as the posterior layer of the left triangular ligament. Thus, the posterior left suprahepatic space and the lesser sac were clearly separated by the lesser omentum and the stomach and over-lapped each other in three dimensions. The posterior left suprahepatic space was located anterosuperior to the lesser sac and in turn was continuous with the gastrohepatic space inferiorly. Carefully researched diagrams of both the midline sagittal and left parasagittal perihepatic spaces were developed. This information has clinical value when the radiologist is called on to drain a left perihepatic abscess.

Abstract 4295 Syngeneic blood and marrow transplantation (BMT) has been applied in the treatment of many malignant or nonmalignant hematologic disorders with no or minimal and transient graft-versus-host disease (GVHD), much less transplant-related mortality (TRM) in contrast to allogeneic BMT, and lower relapse rate compared with autologous BMT. However, limited data in a single BMT center is not sufficient for statistical analysis. To evaluate the clinical outcomes of syngeneic BMT, CSBMT has performed a cooperative survey among BMT centers in mainland, Taiwan, and Hong Kong. From January 1964 to May 2009, 94 transplants from syngeneic donors have been performed in 32 BMT centers. The median age was 20 (1.5 to 51) years old. The diagnosis included AML (29 cases), SAA (26 cases), ALL (17 cases), CML (12 cases), lymphoma (3 cases), MDS (4 cases), neuroblastoma (2 cases), and large granular lymphocytosis (1 case). The main conditioning regimens were CYTBI or BUCY for malignant diseases, none or CY plus ATG for SAA. Bone marrow (BM, 34) or peripheral blood (PB, 49) or both BM and PB (11) as grafts were used. Five patients (SAA 2, AML 3) underwent the same donor's syngeneic BMT twice. One patient with large granular lymphocytosis and 1 case with SAA underwent the same donor's syngeneic BMT thrice. The median follow-up time was 28 months (1 month to 45 years). The median time for white blood cells > 1.0 × 109/L, and platelets > 20 × 109/L was 11 (2-30) days, 13 (0-122) days, respectively. Two patients (2.1%) had grade I acute GVHD (aGVHD), and 4 cases (4.3%) had grade II aGVHD. However, only one patient's specimen was consulted by pathologist. All aGVHD was controlled easily with low-dose steroid. No chronic GVHD was noted. Three-year disease-free survival (DFS) for the patients with nonmalignant disorders was 88.5%. Among them, the longest survivor was living and well for 45 years after transplant. Three-year DFS for the patients with malignant diseases was 62.9%. The overall survival rates at 3 years were 87.9%, and 69.5% for nonmalignant, and malignant diseases, respectively. 22 of 94 patients died after BMT (nonmalignant 3, malignant 19). The only cause of death for the patients with nonmalignant disorders was rejection. Relapse was the main cause of death in patients with malignancies (17/19). TRM was 2.1%. In conclusion, syngeneic BMT is a safe and effective therapeutic option for both nonmalignant and malignant hematologic disorders. Syngeneic donor, if available, should be the first choice in all cases of AA and hematological malignancies in general. The longest survivor of 45 years post-BMT is presented in this series. The good results and advantage of syngeneic BMT cast light on the potential utility of stored autologous placental-cord blood which is shared by the identical twin through the same placenta. Disclosures: No relevant conflicts of interest to declare.

The sheath-helix model is used to analyze the helical slow-wave structure in which the helix turns are considered effectively shorted by the resistive coating on dielectric helix-support rods. Meanwhile, a gap is introduced to simulate the helix tape thickness, and the helix support rods are emulated by an effective dielectric tube and the difference of the radical propagation constant in different regions is taken into consideration. The dispersion equation and interaction impedance of arbitrary field modes are derived. On this basis, the effects of attenuation coating on the attenuation constant, phase constant and interaction impedance are discussed. The results presented here are useful for designing attenuator and improving the high-frequency characteristics of helical slow-wave structure as well as preventing the reflection oscillation and backward-wave oscillation of traveling-wave tubes.