A large-aperture, high-power ultrawideband radiation system with beam broadening capacity.

Due to the limited maximum output power of the pulsers based on avalanche transistors, high-power ultrawideband (UWB) radiation systems usually synthesize plenty of modules simultaneously to achieve a high peak effective potential (rEp). However, this would lead to an increased aperture size as well as a narrower beam, which would limit their applications in intentional electromagnetic interference fields. In this paper, a high-power UWB radiation system with beam broadening capacity is developed. To achieve beam broadening in the time domain, a power-law time delay distribution method is proposed and studied by simulation, and then the relative excitation time delays of the modules are optimized to achieve higher rEp and avoid beam splitting in the beam broadening mode. In order to avoid false triggering of the pulser elements when implementing the beam broadening, the mutual coupling effect in the system is analyzed and suppressed by employing onboard high-pass filters, since the mutual coupling effect is much more severe in the low-frequency range. Finally, a radiation system with 36 modules is developed. Measuring results indicate that in the high-rEp mode, the developed system could achieve a maximum effective potential rEp of 313.6 kV and a maximum pulse-repetition-rate of 20 kHz. In the beam broadening mode, its half-peak-power beam width in the H-plane is broadened from the original value of 3.9° to 7.9°, with a maximum rEp of 272.9 kV. The polarization direction of the system could be flexibly adjusted by a built-in motor.

[A multi-center survey of hypertension and its treatment in patients with maintenance hemodialysis in Shanghai].

OBJECTIVE: To study the prevalence, treatment policy and control of hypertension in patients with maintenance hemodialysis, and to analyze the influencing factors of hypertension control. METHODS: We studied the current status of 1382 patients with maintenance hemodialysis in 11 dialysis centers in Shanghai, among them 809 were male, and 573 were female. Hypertension was defined as systolic blood pressure (SBP)≥140 and/or diastolic blood pressure (DBP)≥90 mm Hg (1 mm Hg=0.133 kPa). Those who had a history of hypertension and requiring antihypertensive therapy were also diagnosed as hypertension though their blood pressure was within normal range during the survey. Hypertension control was defined as blood pressure<140/90 mm Hg before each dialysis session. RESULTS: The prevalence of hypertension in the hemodialysis patients was 86.3%. The treatment rate and control rate in those patients were 96.8% and 25.5% respectively. More than half (50.4%) of patients were treated with only one kind of anti-hypertensive drug, and 34.4% with 2 kinds, 14.2% with 3 kinds, 1.0% with 4 kinds or more. Calcium channel blocker (CCB) was the most frequently prescribed drug (61.0%), followed by angiotensin II receptor blockers (56.4%), centrally acting anti-hypertensive agent (26.4%), beta blockers and alpha, beta-blockers (14.0%). The control rate of hypertension in those hemodialysis people was aggravated by the existence of coronary artery disease. The patients who need more kinds of antihypertensive agents have a poorer control rate of hypertension. The hypertension control rate elevated significantly with the adequate hemodialysis. CONCLUSIONS: There is a very high prevalence of hypertension in maintenance hemodialysis patients. Although the treatment rate is high, the control rate is unsatisfactory. So the control of hypertension in hemodialysis patient is still a clinical challenge. Appropriate dialysis adequacy, reasonable use of erythropoietin, treatment of heart disease and judicious use of antihypertensive drugs may be helpful to improve the clinical outcome.

[Effects of metal-catalyzed oxidation on the formation of advanced oxidation protein products].

OBJECTIVE: To explore the relationship between metal-catalyzed oxidation (MCO) and the formation of advanced oxidation protein products (AOPPs). METHODS: Specimens of human serum albumin (HSA) and pooled plasma were collected from 3 healthy volunteers and 4 uremia patients were divided into 3 groups: Group A incubated with copper sulfate solution of the concentrations of 0, 0.2, or 0.5 mmol/L, Group B, incubated with hydrogen peroxide 2 mmol/L, and Group C, incubated with copper sulfate 0.2 or 0.5 mmol/L plus hydrogen peroxide 2 mmol/L. 30 min and 24 h later the AOPP level was determined by ultraviolet visible spectrophotometry. High-performance liquid chromatography (HPLC) was used to observe the fragmentation effect on plasma proteins. Ninhydrin method was used to examine the protein fragments. The scavenging capacity of hydroxyl radical by macromolecules was measured so as to estimate the extent of damage for proteins induced by MCO. RESULTS: (1) The AOPP level of the HSA and plasma specimens of the uremia patients increased along with the increase of cupric ion concentration in a dose-dependent manner, especially in the presence of hydrogen peroxide (P < 0.05). (2) Aggregation of proteins was almost negligible in all groups, however, HPLC showed that cupric ion with or without hydrogen peroxide increased the fragments in the HAS specimens (with a relative molecular mass of 5000) and uremia patients' plasma proteins (with the molecular mass 7000). (3) The plasma AOPP level of the healthy volunteers was 68.2 micromol/L +/- 2.4 micromol/L, significantly lower than that of the uremia patients (158.5 micromol/L +/- 8.2 micromol/L). (4) The scavenging ability to clear hydroxyl radical by plasma proteins of the healthy volunteers was 1.38 -9.03 times as higher than that of the uremia patients. CONCLUSION: MCO contributes to the formation of AOPPs mainly through its fragmentation effect to proteins.

Experimental study on the clinical effects of Xiaoru Sanjie Jiaonang on mammary glands hyperplasia and ki-67.

OBJECTIVE: This study aims to observe the effect and mechanism of Xiaoru Sanjie Jiaonang (XRSJ) on the treatment of mammary gland hyperplasia, and provide a theoretical basis and clinical evidence for clinical expansion. METHODS: Japanese white rabbits were randomly divided into three groups: high-, middle- and low-dose groups; Xiaoyao Pill group; model control group; normal control group. The observation points were as follows: before XRSJ administration, three months after XRSJ administration, and three months after XRSJ discontinuance. Changes in breast height, morphological changes of the mammary gland under a light and electron microscope, and the expression of ki-67 were observed. At the same time, patients diagnosed with mammary gland hyperplasia at an Outpatient Clinic were selected and divided into treatment groups. These patients received XRSJ and Xiaoyao Pills, respectively, for one month, while patients in the control group did not receive any drug treatment. Clinical efficacy was observed while rechecking at the Outpatient Clinic after three months. Treatment with a therapeutic dose of XRSJ could significantly reduce breast height, decrease the number of lobules and acini in hyperplastic mammary glands and the layer number of ductal glandular epithelial cells, substantially lower the content of serum estradiol (E2), significantly downregulate the expression of ki-67 protein in mammary tissues, and inhibit mammary gland hyperplasia. CONCLUSION: XRSJ treatment can relieve mammary tissue hyperplastic lesions, reduce E2 levels and downregulate the expression of ki-67. It has a significant therapeutic effect on mammary gland hyperplasia.

[Effects of calcium fertilizer on the development, survival, and feeding of B-biotype Bemisia tabaci on Euphorbia pulcherrima].

This paper studied the development, survival, and feeding of B-biotype Bemisia tabaci on Euphorbia pulcherrima under the conditions of 26 +/- 1 degrees C and 60% - 80% relative humidity after applying calcium fertilizer, taking applying fresh water as the control. There existed significant differences in the developmental duration of B. tabaci between treatment applying calcium fertilizer and the control. After applying calcium fertilizer, the egg stage of B. tabaci shortened significantly, and the development from egg to adult took 20.18 days (for the control, it took 18.72 days). However, there were no significant differences in the survival rates of B. tabaci at different development stages between the two treatments. The feeding of B. tabaci on E. pulcherrima induced the plant leaf chlorophyll fluorescence parameters changed, i. e., the photochemical efficiency (Fv/Fm), photochemical quenching coefficient (q(p)), light use efficiency (alpha), maximum photosynthesis rate (rETRmax), and tolerance to light (I(k)) decreased significantly, while the non-photochemical quenching coefficient (NPQ) had a significant increase. After applying calcium fertilizer, the plant leaf photoinhibition parameter (beta), rETRmax, and I(k) had less difference with th e control. The nail polish blot observation on the lower epidermis structure of plant leaf showed that calcium fertilizer could effectively compensate the decrease in the photosynthesis of E. pulcherrima damaged by B-biotype B. tabaci.