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This paper reports an investigation of different persulfate (PS) activations, including PS at 20 °C (PS), thermally activated PS at 70 °C (T-PS), ferrous-ion activated PS at 20 °C [Fe(II)-PS)], hydrogen peroxide activated PS at 20 °C, and sodium hydroxide activated PS at 20 °C, for degradation of the herbicide 2,4-dichlorophenoxyacetic acid (2,4-D) in aqueous phase. Several findings were made in this study including the followings: the 2,4-D degradation rates in T-PS and Fe(II)-PS systems were higher than other systems. However, complete degradation of 2,4-D and associated derivatives can be reached in all oxidation systems, with various reaction times. When considering the results of PS consumption during the 48 h reaction time to reach complete 2,4-D degradation, the T-PS system consumed all of the PS while only 10 % of the PS was consumed in the Fe(II)-PS system. The evaluation of optimum PS and ferrous ion doses indicated that under a fixed initial PS concentration, increasing Fe2+ concentration generally increased the amount of initial rapid degradation of 2,4-D and dissolved organic carbon. However, the effectiveness of the Fe(II)-PS system may be inhibited by the presence of excess iron. When a fixed level of Fe2+ was employed, various PS concentrations resulted in approximately equal 2,4-D degradation. The Fe(II)-PS system was found to be sensitive to the initial Fe2+ concentration, and the presence of soil revealed minor influence on the 2,4-D degradation by the Fe(II)-PS system. These findings indicate that the iron-activated PS process may be an effective method for remediating 2,4-D contamination.

Early studies of the retinoblastoma gene (RB) have uncovered its critical role as a regulator of the G(1)/S cell cycle phase progression. Surprisingly, genetic approaches in mammals and nematodes have also shown RB controls cell lineage specification and aspects of differentiation. The RB gene product accomplishes this by diverse mechanisms such as by interacting with tissue-specific transcription factors, enhancing RNA interference, and modifying chromatin structure. We review recent studies uncovering novel mechanisms by which RB works in several cell lineages and we provide perspectives on how these new findings might relate to RB tumor suppression.

This paper describes a process by which computer-aided design methods are used for the tolerance charting of products with angular features. If a product contains one or more angular features, such as chamfers and tapered surfaces, radial or normal machining of the features will result in axial dimension changes. In this paper, basic trigonometric formulae are first presented to explain the phenomenon of tolerance accumulation. In the process of tolerance charting, dummy cuts are included to reflect the corresponding dimensional changes due to indirect machining. With the assistance of flags and linked lists, the system proposed can automatically identify all dimensional chains which are associated with either regular cuts or dummy cuts. Moreover, optimisation techniques are recommended to allocate the allowable tolerances as specified by blueprints. In the search for an optimal design, the total manufacturing cost defined by the working tolerances is the objective function to be minimised.

In this study, the dispersion relation of the waves in the plasma guided by a coaxial dielectric loaded slow wave structure has been derived and solved. Results show that there are two different waves propagating in this structure. The associated physical mechanisms will be presented.

Background Attrition can pose significant barriers to treatment success of depression; its contributing factors and impacts on treatment outcome need further clarification. Current study aimed to describe patterns of treatment attrition, to examine associated demographic and clinical determinants and to test whether and how attrition affects outcome of depression in a national cohort of adults treated for depression. Material and methods All adult patients prescribed with antidepressants for depression (n=216,557) in 2003 were identified from the National Health Insurance Research Database in Taiwan. Based on individuals’ clinical visit and antidepressant prescription, three attrition types, i.e., non-attrition, returning attrition and non-returning attrition, and their demographic/disease characteristics were identified. The relationships between attrition type and remission outcome over an 18-month follow-up period were further explored. Results Factors pertaining to disease characteristics (severity of depression, comorbidities, painful physical symptoms and past treatment history) and clinical practice (physician specialty and choice of antidepressants) were associated with attrition and remission outcome at 18-month follow-up. Patients remaining in treatment within the first three months were associated with higher odds of having sustained remission (OR=1.21; 99% CI: 1.16, 1.27) and lower odds of having relapses/recurrences (OR=0.20; 99% CI: 0.19, 0.21) over the 18-month period, compared to those returning attriters. Conclusions Early attrition has significant negative impacts on antidepressant treatment outcome; it hence needs to be minimized through shared decision-making, exchange of treatment preferences and proper patient-physician communication. Based on current understanding, further efforts to reduce early attrition are highly warranted.

The present paper reports that the short-term relapse could be artificially made by the application of the experimental method, and thus we established the monkey model of the short-term relapse. According to the experimental design, when the parasitemia was detected in rhesus monkeys infected with sporozoites of Plasmodium cynomolgi, a combined therapy of pyronaridine 6 mg/kg body weight, artemether 10 mg/kg and chloroquine 20 mg/kg once daily for 3 days was carried out to clear the erythrocytic parasite and then the short-term relapse was observed in the animal follow-up for 100 days. The combined therapy was given again when relapse occurred. One onset of relapse occurred on 47 days after therapy in monkey M194 infected with sporozoites 11 x 10(3). In M195 infected with sporozoites 55 x 10(4), relapses occurred for 3 times on 30, 37 and 51 days respectively after medication, but during a follow-up period of 200 days, no relapse was shown in M192 and M193 infected with sporozoites 50 and 55 x 10(2), respectively. The results showed that the frequency of the short-term relapse was relative to the sporozoites inoculation, and sporozoites less than 11 x 10(3) were not suitable for making short-term relapse in animal model. No long term relapse could be seen in all the 4 monkeys until 400 days. Under existing conditions that the relapse was generally explained with hypnozoite assumption, the establishment of animal model of short-term relapse could be tenable.(ABSTRACT TRUNCATED AT 250 WORDS)

In this study, the antigen recognized by the protective McAb M26-32 in erythrocytic stages of P. yoelii was localized by immuno-electron microscopy with LR Whithe resin embedding and colloidal gold probe cytochemical techniques. The results indicated that the antigen which reacts specifically to McAb M26-32 was mainly localized within the cytoplasm of early and late trophozoites, schizonts and merozoites, being the common antigen of asexual blood stages of the plasmodium. The amount of the antigen was on the increase during the development of trophozoite, while a portion of the antigen might be transported outward by exocytosis of the parasites and then be localized in the cytoplasm of the infected erythrocytes adjacent to the parasites.

A monkey was infected with sporozoites of Plasmodium cynomolgi from Vietnam. Parasitemia was detected on the 8th day with a starting density of 17/100 white blood cells. 22 hours after that time, many EE schizonts appeared with an average density of 3.74 +/- 0.66 per mm3 hepatic tissue in liver biopsy specimens from the monkey. Most of the EE schizonts were immature and grew at an uneven rate, having an average diameter of 34.22 +/- 7.28 microns but some of them even remained 15.75 +/- 2.47 microns in diameter similar to the EE schizonts on the 6th day. The results showed that the EE schizonts of Plasmodium cynomologi were asynchronous in growth. The authors suggest that the release of merozoites from liver might be a successive process for many times, and not to be completed at a time.

Our previous report that the EE merozites of Plasmodium cynomolgi from Vietnam continuously released from the liver to the blood circulation was further demonstrated in this report. Monkeys were given pyronaridine 24 mg/kg.d x 6 after being inoculated intravenously with 32 x 10(5) sporzoites of P. cynomolgi. Thick blood film examination was conducted two times daily till the day when trophozoites were detected. Under the residual action of blood schizontocied, a special ring form parasitemia at low patasite-density was detected for more than 30 days. As the ring forms of P. cynomolgi were demonstrated to be susceptible to pyronaridine in our previous experiments, it might be inferred that these ring forms derived from EE merozites released not for once but continuously for 30 days or longer.

SD rats and three strains of mice were infected with Plasmodium yoelii yoelii By265 strain by intravenous inoculation of sporozoites via tail vein. Liver tissues were taken 42 hours after infection and serial sections were made and stained by Colophonium-Giemsa method for microscopic examination. The ratio of the average value of major diameter/minor diameter of exoerythrocytic(EE)schizonts of Plasmodium yoelii yoelii in rats and mice of ICR/JCL, C57BL, KM strains was 35.81 +/- 4.56 microns/29.72 +/- 4.08 microns, 28.08 +/- 4.66 microns/23.66 +/- 4.44 microns, 28.14 +/- 4.16 microns/23.63 +/- 3.77 microns, 23.80 +/- 2.42 microns/21 +/- 0 microns, respectively. The results showed that the development of EE schizonts of Plasmodium yoelii yoelii was not synchronous. The EE schizonts in the rat liver were surrounded by Kupffer cells, monocytes and monocyte-derived macrophages. Since the parasitemia disappeared rapidly in rats, and EE schizonts were not well developed in KM strain, it may be considered that ICR/JCL and C57BL strains are more suitable as vertebrate host in Plasmodium yoelii yoelii-Anopheles stephensi system model (Figs. 1-9).

Cercopithecids did not arrive in China until the latest Tertiary, relatively late in their evolutionary history.