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As a refractory industrial solid waste, high-alumina fly ash is discharged into nature in large quantities, causing serious environmental harm. The extraction of valuable components, such as aluminum, from high-alumina fly ash has become a research hotspot at home and abroad. The shortcomings of traditional alumina extraction from high-alumina fly ash include long technological processes, large amounts of waste acid and alkali, and serious equipment corrosion. A novel method for alumina preparation by electrotransformation AlCl3 solution(EAS) under NH4Cl catalysis with injected CO2 has been proposed by Northeastern University. The process has advantages, such as short flow and no waste acid discharge. In this study, the influence of initial NH4Cl concentration in the cathodic chamber on solution pH, phase and morphology of electrotransformation products, phase, D(50) and D(90) of roasting products, and Al recovery rate were examined. Simultaneously, EAS was examined and compared with and without injected CO2, as well as EAS under NH4Cl catalysis with and without injected CO2. The results showed that, when the solution in the cathodic chamber was NH4Cl with CO2 injection, with electrotransformation time extension, pH increased slowly and the morphology of electrotransformation products were all rough and fluffy block structures. Increasing initial NH4Cl concentration effectively improved the product crystallization states, roasting products D(50) and D(90), and Al recovery rate.

Atomic clocks, which lock the frequency of an oscillator to the extremely stable quantized energy levels of atoms, are essential for navigation applications such as deep space exploration

噬菌体是一类可以感染细菌、真菌、放线菌或螺旋体等微生物的病毒的总称。噬菌体被应用于临床抗细菌感染治疗已有100多年的历史，但因抗菌药物的发现及广泛使用使其逐渐淡出了人们的视线，仅少部分国家与学者仍坚持临床应用至今。在抗菌药物耐药问题日益严重、临床应对策略匮乏的今天，噬菌体治疗重新回到了人们的视野中。噬菌体作为抗细菌感染治疗的优势为特异性强，仅针对目标宿主菌，对周围其他菌株无影响，当目标宿主菌被杀死后衰减并被清除。自然界中噬菌体资源丰富，而且它们与细菌共同进化，几乎在任何时候均可根据临床的需求分离到针对致病细菌的噬菌体。另外，由于抗菌机制不同于现有的抗菌药物，噬菌体治疗对于所谓的"超级细菌"同样有效，且可破坏生物被膜，降低"超级细菌"的耐药性，与抗生素联合应用有很好的协同作用。噬菌体治疗也有其局限性，如噬菌体的分离、纯化与保存有一定难度。本文主要讨论噬菌体临床治疗的历史与现状，并预测噬菌体的发展潜力。.

Glutamine synthetase (GS) in nodule cytosol plays a major role in the assimilation of the ammonium produced by biological nitrogen fixation. To characterize the GS protein family in Glycine max root nodules, the catalytical properties of 2 GS1 isoenzymes (GS1β1 and GS1γ1) were compared in this study. Although, GmGS1β1 and GmGS1γ1 have very similar kinetic characteristics, they also exhibit distinct enzymatic properties in terms of thermal stability and the transferase to synthetase activity (GSt/GSs) ratios. The results demonstrated that GmGS1γ1, which displayed lower thermal stability and GSt/GSs ratios than GmGS1β1, might be considered as superior isoform to participate in the efficient assimilation of ammonia only when it is needed. Also, it is proposed that the difference of enzymatic properties between isoforms contribute to their differential roles in ammonia assimilation under variable internal and external environments.

CaO–MgO–SiO2–Al2O3–Cr2O3–Fe2O3 slag systems with different basicities and different Fe2O3 contents were prepared using reagent powders and experimented cooling from melt to 1400°C for crystallisation. X-ray diffraction, Scanning Electronic Microscopy and Energy Dispersive Spectrometer were used for slag sample characterisation. It was established that the basicity of the slag changed the mineralogical phases, while variation of Fe2O3 content in slag with the same basicity did not affect the main crystalline phases. The results showed that most of the Cr2O3 was incorporated into Mg(Al,Fe,Cr)2O4 spinel solid solution and content of Cr2O3 in spinel phase decreased with increasing of the basicity (CaO/SiO2) and the Fe2O3 content.

The aim of this study was to compare the pharmacokinetic characteristics of phloroglucinol between an orally disintegrating tablet and an orally lyophilized tablet of phloroglucinol in healthy volunteers under fasting condition.A rapid and simple method based on high-performance liquid chromatography-tandem mass spectrometry (HPLC-MS/MS) method has been developed and validated for the determination of phloroglucinol in human plasma. The plasma sample was prepared by liquid-liquid extraction, and paracetamol was chosen as the internal standard. Phloroglucinol and IS were separated on a C18 column with a mobile phase consisted of methanol/water (80:20 v/v) with 0.02% formic acid. HPLC-MS/MS analyses were performed on a triple- quadruple tandem mass spectrometer by monitoring protonated parent→daughter ion pairs at m/z 125.0→56.9 for phloroglucinol, and m/z 150.2→107.0 for paracetamol (IS). The method was the high sensitivity with a lower limit of quantification (LLOQ) of 1.976 ng/mL.Drug and IS were detected by HPLC/MS/MS with negative electrospray ionization (ESI). Accuracy and precision for the assay were determined by calculating the intra- and inter-batch variation of quality control (QC) samples at three concentration levels. The relative standard deviation (RSD) was less than 15.0%. The detection and quantitation of drug and IS within 4.5 min make this method suitable for high-throughput analyses. In this study, the Cmax of phloroglucinol were calculated to 515.6 ± 134.4 ng/mL and 536.0 ± 144.8 ng/mL for the test drug and the reference drug, respectively. The AUC0-t values were 459.5 ± 81.03 ng·mL-1·h and 491.8 ± 95.17 ng·mL-1·h for the test drug and the reference drug; 24 subjects completed the study, respectively. The geometric mean ratio (GMR) and the 90% confidence intervals (CIs) of Cmax and AUC0-t of phloroglucinol were 97.1 (90.2-103.9) and 93.8 (88.7-99.2), respectively.The method was employed for the first time during pharmacokinetic studies of phloroglucinol in human plasma following a single dose of phloroglucinol 160 mg tablets. There was no significant difference in pharmacokinetic profiles between the two treatments.

This paper considers the existence of almost periodic solutions of a N-dimension non-autonomous Lotka-Volterra model with delays. The method is based on exponentialdichotomy and Schauder xed point theorem. The obtained results generalize somepreviously known ones.

An experiment was carried out to investigate the effect of salt stress on Periploca sepium Bunge seedlings using three levels of salinity, 50 mmol/L, 100 mmol/L, and 200 mmol/L sodium chloride (NaCl) solution. The results showed that growth parameters and net photosynthetic rate (P n ), stomatal conductance (G s ) of Periploca sepium Bunge were enhanced under low salinity levels (50 mmol/L NaCl), which reduced strongly with increasing salinity levels. Under 100 mmol/L NaCl and 200 mmol/L NaCl stress, the decline of P n was mainly caused by non-stomatal factors. The water use efficiency (WUE), apparent light use efficiency (LUE), carboxylation efficiency (CUE) were enhanced under low salinity levels (50 mmol/L NaCl), the maximum value of WUE was observed at 100 mmol/L NaCl, the minimum value of WUE was observed at 200 mmol/L NaCl, the LUE, CUE were reduced by 52% and 47%, at 200 mmol/L NaCl, respectively, compared to control. Activities of the antioxidative enzymes superoxide dismutase (SOD), peroxidase (POD), and catalase (CAT) were enhanced by low salinity treatment (50 mmol/L NaCl), but CAT activity decreased at 200 mmol/L NaCl stress. Malondialdehyde (MDA) was non-significant com pared to the control under low salinity levels (50 mmol/L NaCl), the maximum value was observed at 200 mmol/L NaCl. These results suggest a possibility to improve saline soil utilization of Periploca sepium Bunge in Yellow River Delta region.

Resistivity measurements were performed on single crystals of the superconducting cuprates (Nd,Ce)2CuO4 (NCCO) at zero and high magnetic fields. By suppressing the superconducting phase, the well-known log(1/T) diverging resistivity was observed at low temperature. Surprisingly, for samples with an insulator-like upturn of resistivity in the normal state at zero field, the diverging resistivity induced by high field in the superconducting region clearly deviates from the insulator-like behaviour in the normal state at a certain temperature (deviating temperature). The results indicate that the field-induced resistivity has a different nature from that of the normal state. Antiferromagnetic order is considered to play a crucial role in the occurrence of the log(1/T) resistivity.

The presence of silent cerebral infarction (SCI) increases the risk of transient ischaemia attack, symptomatic stroke, cardiovascular disease and dementia. Mean platelet volume (MPV) is a surrogate marker of activated platelets and is considered a link between inflammation and thrombosis. In addition, MPV is a risk predictor for cardiovascular disease, stroke and overall vascular mortality.The purpose of the study was to assess the MPV levels in SCI patients.A cross-sectional study was conducted to evaluate the association between MPV and SCI in 2215 subjects (1385 men and 830 women).The participants with SCI had higher MPV levels than those without SCI (10.4 ± 1.3 fL vs. 9.2 ± 1.2 fL; P0.001). Moreover, the subjects with a high MPV had a higher prevalence of SCI. Multivariate logistic regression analyses revealed that the odds ratios and 95% confidence intervals for SCI according to MPV quartiles were 1.000, 2.131 (1.319-3.444), 3.015 (1.896-4.794), 7.822 (4.874-12.554) respectively (P0.001).MPV is a novel index for SCI regardless of classical cardiovascular risk factors.

Glare points are the intensity maxima seen when a water drop illuminated by a wide beam is viewed from a certain direction and imaged. We show that good resolution in both the scattering angle and the glare point position can be achieved only if the size parameter x = 2pia/lambda is1 and that the positions of the glare points can be computed by a Fourier transform from the familiar Lorenz-Mie scattering function. Sample computations made with x = 10,000 and x = 20,000 are presented. Glare points corresponding to rays that have suffered as many as 15 internal reflections can be identified, in agreement with experimental findings.

Cryogenic microwave oscillators offer the highest short term stability of any frequency sources.

The objective of the current study is to discuss the problems related to how data is used to calculate Years Lost with Disability (YLD) with the method recommended by the World Bank. The study includes collecting useful data, estimating disease duration and average age of disease onset, adjusting incidence and prevalence data by means of a software programme, DISMOD (Harvard University IncidencePrevalence Model), and assessing the importance of YLD calculation for different diseases. Remission and fatality rates of 3 diseases were estimated by experts at 2 round consultations. Incidence rates, disease duration and average age of disease onset were calculated and adjusted by DISMOD. YLD due to schizophrenia is the highest among 4 diseases in two regions. YLD is 18.88% in disability adjusted life year for 4 diseases in Xiacheng District, and 19.97% in Fuyang County. Available data can be used for the calculation of YLD after being adjusted. DISMOD is a useful instrument to test the internal consistency of incidence, prevalence, remission and fatality rate. The adjusted data are acceptable to experts and DISMOD. To get rational remission and fatality rates, we can use a cohort method through expert consultations. To reflect overall burden of disease, YLD calculation should be used.

Vasectomy has been reported to be associated with an increased risk of prostate cancer in western countries. A hospital-based case-control study was conducted in 12 cities in China to evaluate the relationship between vasectomy and prostate cancer risk in China, a low-risk country with rising incidence and increasing use of vasectomy. Interviews were conducted with 138 histologically confirmed prostate cancer cases diagnosed during 1989-1992 and 638 controls (158 hospital cancer, 158 hospital noncancer, and 322 neighborhood controls) of similar ages. Vasectomy at least 10 years prior to interview was reported by 10% of the cases versus 3% of the controls. Odds ratios for prostate cancer associated with vasectomy were 2.0 (95% confidence interval, 0.7-6.1), 3.3 (95% confidence interval, 1.0-11.3), and 6.7 (95% confidence interval, 2.1-21.6), respectively, when hospital cancer, hospital noncancer, and neighborhood controls were used for comparison. Although detection bias is of concern, the data suggest that in China, men with a history of vasectomy may experience an increased risk of prostate cancer.This paper reports the findings of a hospital-based case-control study that was conducted at major teaching hospitals in 12 cities in China. China reports the lowest incidence in prostate cancer of over 100 registries reporting cancer incidence. This investigation evaluated the relationship between vasectomy and prostate cancer and attempted to identify any etiological factor. A total of 138 study patients (index cases) were identified. Controls used in this study included a cancer control and a noncancer control from the same hospital, and 2 neighborhood controls. Chances of having prostate cancer were statistically determined by logistic regression analysis with age group adjustments made. The analysis reviewed 138 cases and 638 controls. Results indicate that, regardless of the variable control used for comparison, an increased risk of prostate cancer was associated with having had a vasectomy. Statistical odds ratio was 2.0 for hospital cancer controls (95% confidence interval [CI]; 0.7-6.1); 3.3 for hospital noncancer controls (95% CI; 1.0-11.3); and 6.7 for neighborhood controls (95% CI; 2.1-21.6). The authors conclude that, as reported for men in Western countries, Chinese men who have had a vasectomy are at significantly increased risk for developing prostate cancer compared to men who never have had a vasectomy. They report a near 2-fold increase in risk (vasectomy vs. non-vasectomy) in developing the disease. Conclusions about cause and effect are premature, but these findings warrant further investigation of several issues. These include: changes in the endocrine system due to vasectomy; systematic and local immunity changes after vasectomy; and other possible biochemical factors that enhance/inhibit cancer growth in the prostate gland.

Flame atomic absorption spectrophotometric methods were developed for, arsenic, selenium, copper, zinc and iron in hair samples. Data from blackfoot disease patients at five clinical stages were compared with those from healthy controls. The copper and zinc concentrations showed only slight differences in all clinical stages, which indicated the less relation to blackfoot disease. The decrease of selenium and iron in all stages was attributed to the antagonistic effect of arsenic; arsenic increased in the first and second stages, but decreased in the later stages. The decrease of selenium and iron during the progression of the disease is thought to be due to persistence of the antagonistic effect of arsenic in the initial stages, so that very low concentrations of selenium are found in the advanced stages, despite the later decrease of arsenic. There was also a progressive decrease of iron with advance of the disease, and the later stages also showed a decrease in haemoglobin. It was shown that arsenic is a major cause of blackfoot disease, and that it antagonises selenium and iron, which decreased in the advanced clinical stages of the disease.

The gas bubbles in liquid are the strong scatters of the sound propagation in such liquid. A liquid containing microbubbles is used as an effective ultrasound contrast agent in medical diagnosis to improve the contrast of the ultrasonic image. However, the existence of bubbles in liquid may enhance its nonlinearity parameter. In our previous paper, the preliminary results of some ultrasound contrast agents were reported and their large values of the nonlinearity parameter were obtained. This paper is devoted to an experimental demonstration of the influence of microbubbles on the nonlinearity parameter B/A values. These include measuring the dependence of B/A values of Echovist 300 on time. Results show that B/A values decrease with time (from 2678 to 16 over 45 min). B/A values of human blood with a different portion of Echovist were also studied. Larger B/A values are obtained with more Echovist. B/A values of a kind aqua, such as 76% Injectio Meglumini Diatrizoatis Composita (MDC), were studied before and after sonication with different bubble contents. Results indicate that the values of nonlinearity parameter depend on the presence of microbubbles obviously. Some explanation of this effect is discussed. [Work supported by NSF of China.]

We use combined second-sound attenuation and temperature-gradient measurements to determine the vortex line density, anisotropy, and the drift of the vortex tangle as a whole in counterflowing helium II from 1.27 to 2.10 K. We find a much higher probability for vortex lines in the tangle to be transverse to the flow than along the flow. We also find that, at least below 2.1 K, the vortex tangle drifts with the superfluid toward the heater.

On admission to the hospital, a splenectomized man was found to have 85% of his erythrocytes parasitized by Babesia microti. His extensive parasitemia allowed for direct study of the morphology and ultrastructure of this organism as it appears in human infection; the need for animal inoculation and rescue techniques was thus eliminated. Positive characteristics (other than the tetrad form) that are diagnostic for babesiosis were identified. By transmission and scanning electron microscopy, parasite-induced changes in the erythrocyte membrane were observed; these alterations may explain the hemolysis seen in babesiosis. Factors that may have allowed the patient to sustain such high-level parasitemia are considered. The experience with this patient confirms that exchange transfusion is a reliable, rapid method for reduction of the parasite load in serious infection with B microti.

One of every five Americans will be 65 or older by the year 2030. At least 50% of Americans will live to be 85 by the year 2050. To meet the needs of this burgeoning population, the authors suggest, medical centers should recruit geriatricians, target and expand services, establish geriatric programs and network with community organizations.

This final report summarizes the research activities under the 'Systematic Study of Light Scattering by Irregularly Shaped Particles.' The beginning one and one-half years were devoted to the analysis of existing experimental data and the related theoretical light-scattering studies, in parallel with the reconstruction, renovation and calibration of the microwave analog scattering facility then relocated from the Albany, N.Y. area. The following one and one-half year period was devoted to actual measurement tasks and analysis of data in our original proposal; e.g., the investigations of scattering by interacting spheres and by particles with rough surfaces. Simultaneous with these measurements a number of 2:1 finite cylinders were also measured on their extinction properties when they were either preferentially or randomly oriented in space.

Postnatal neurogenesis and reconstitution of the neuronal layer of the vomeronasal epithelium have been demonstrated in adult garter snakes following vomeronasal axotomy. Two weeks following axotomy the vomeronasal epithelium was depleted of its bipolar layer but the basal, undifferentiated cells were actively proliferating. In subsequent weeks the undifferentiated cell layer continued to increase its cell population through mitosis and began to occupy the neuron-depleted zone of the receptor cell column. Four weeks following axotomy the denervated epithelium contained an expanded Ud cell layer which occupied the basal one-half to two-thirds of the receptor cell column. The cells at the base of the expanded Ud cell layer were morphologically similar to Ud cells in a normal epithelium whereas the cells at the apex of the columns resembled normal differentiating neurons. A few necrotic cells could still be detected within the apical, cell-depleted zone. By the eighth post-operative week the receptor cell column was fully occupied with cells formed as a result of Ud cell proliferation. The most apical cells, 6-10 cells deep, were morphologically similar to normal bipolar neurons with a dendritic process reaching the lumen of the VN organ. The remaining cells were morphologically similar to normal differentiating or Ud cells. Sixteen weeks following axotomy a larger portion of cells in the receptor cell column were fully differentiated bipolar neurons. The Ud cell population was reduced and, as in the normal epithelium, occupied only the basal portion of each receptor cell column. The regenerated neurons of the VNO were capable of synthesizing and transporting macromolecules to the telencephalon as demonstrated by autoradiography following intraepithelial injections of [3H]proline. Newly formed axons terminated in the accessory olfactory bulb within 8 weeks following axotomy. These results support the view that the basal Ud cells were the source of neurons in the regenerating vomeronasal organ and demonstrate a dynamic process of neuronal proliferation, differentiation and maturation in the denervated vomeronasal epithelia of adult garter snakes.

With the corrections and developments on the theory of light scattering by spheroidal particles, we have computed the scattering parameters of both prolate and oblate spheroids with high aspect ratio 7:1 in dielectric and metallic cases. The theoretical results come out to be satisfactory if compared with our microwave measurements in P-Q plot form.

A selected number of our microwave extinction measurement results on preferentially/randomly oriented nonspherical particles are presented. These particles span in size near the first major resonance, possess refractive indexes characteristic of natural aerosols, and have axisymmetry in shape, such as spheroids, cylinders and dumbbells. Subtle dependence of light obscuration on particle orientation is shown in our standardized form of P,Q plots. Such a P,Q plot is a cartesian display of the complex scattering amplitude S(0) versus particle orientation (X,ψ) at scattering angle 0 = 0 and contains detailed information on the single-particle obscuration process in perhaps the most comprehensive form. We also routinely deduce C ext , the extinction cross section ext' averaged over random particle orientations, from such a P,Q plot. The ensuing, vivid overall pictures of obscuration by a number of randomly oriented nonspherical particles are also depicted in graphs of Q ext,v versus ρv, showing the volume-equivalent extinction - efficiency averaged over random orientations versus the volume-equivalent phase-shift parameter of each particle. Comparisons with theoretical predictions, where applicable, are also shown in these graphs.

The neuroleptic malignant syndrome (NMS) developed in a 32-year-old man following fluphenazine enanthate administration. Hypercalcemia was initially present, perhaps reflecting release of calcium from skeletal muscle stores. The elevated serum calcium levels support the existence of a peripheral muscle abnormality in the pathogenesis of the NMS and provides another point of similarity between NMS and malignant hyperthermia.

Microwave analog measurements of θ=0° scattering by particles of various shape and refractive indexes are presented. The scattering targets are non-isotropic spheres, aggregates of 2n (n=1,2,3) identical spheres, and stacked 7-cylinder rough particles. Both the orientation and the physical properties of the target produce signatures in the extinction and polarization curves. Theoretical explanations are presented wherever possible.

Although fish have been used repeatedly in bioassays of toxicity of petroleum oils, little information is available for marine species (Nelson-Smith 1970, 1972). Anderson and colleagues ( 1974) studied the effects of crude and fuel oil on survival of estuarine species. Using a marine catfish readily available, the effects of a fuel oil on survival, feeding behavior and heart rate are examined. The latter has frequently been used as a sensitive test for environmental stress.

Some results of experimental studies on microwave scattering by artificially constructed axially symmetric spheres with anisotropic refractive indices are presented. An approximation using Mie theory for spheres with appropriate orientation dependent indices of refraction is shown to provide a good explanation of the observed dependence of the complex forward-scattering amplitudes on target orientation.

A method for obtaining detailed dependence of extinction cross sections on the orientation of nonspherical particles is described. The results of experimental scattering studies of several different particles are presented.