Search

Objective To assess the association between the variability of blood pressure (BP) readings within an initial clinic visit, the variability within subsequent visits and the variability between visits over 1 week in a general population. Methods This study included 1401 adult residents, who were not taking antihypertensive drugs, having BP measurements at three visits over 1 week. The difference between maximal and minimal BP readings (ΔBP), ΔBP/BPm (the mean BP value in a visit), the standard deviation (SD) and coefficient of variation (coefficient of variation = SD × 100/mean) of three BP values in each visit were used to estimate the within-visit BP variability (BPV). The SD and coefficient of variation of all nine BP readings over the three visits were calculated as SD9 or CV9 to reflect the overall BPV during the study visits. The SD and coefficient of variation on the mean BP values (BPm) of three visits were computed as SD-3 or CV-3, whereas the difference between maximal and minimal BP in three visits was computed as ΔBP-3 to estimate visit-to-visit BPV. The average BP or HR was the mean values of nine BP or HR readings over three visits. Results The systolic and diastolic mean BP (SBP and DBP) decreased from the first to the third visit. The ΔBP, SD and coefficient of variation for both SBP and DBP at the first visit were positively and significantly correlated with the corresponding variables computed at the second and third visits, as well as with overall BPV (ΔBP9, SD9 and CV9). A positive correlation was also found between overall BPV and visit-to visit BPV (SD-3, CV-3 and ΔBP9). Multivariate analysis showed: no association between average SBP and systolic coefficient of variation or ΔBP/BPm but a negative association between average DBP and coefficient of variation or ΔBP/BPm for DBP at the first visit, DBP-3 and DBP9. Age was positively correlated with coefficient of variation or ΔBP/BPm for SBP at the first visit, SBP-3 and SBP9, and correlated with coefficient of variation and ΔBP/BPm for DBP only at the first visit. Conclusion In a general population, within-visit BPV at an initial visit is associated with within-visit BPV at subsequent visits and with visit-to-visit BPV over three visits within 1 week.

In China, there are approximately 250 million adults who have hypertension with low rates of awareness, treatment and control. Changes in lifestyles at a population level have the potential to enhance or deteriorate the prevention and control of hypertension. We used data from a regional hypertension survey to examine the impact of 2/1 mm Hg decreases or increases in population blood pressure on hypertension prevalence, and rates of unawareness of the hypertension diagnosis, treatment, and control. The primary analysis was based on the average blood pressure of respondents from three visits and a diagnostic threshold of 140/90 mm Hg for hypertension. Secondary analyses examined average blood pressure from the first survey visit and also a diagnostic threshold of 130/80 mm Hg for hypertension. The baseline hypertension prevalence was 33.4%, and rates of unawareness of the hypertension diagnosis, treatment, and control were 74.2%, 25.8%, and 9.7%, respectively. Decreases or increases in blood pressure by 10/5 mm Hg resulted in changes in hypertension prevalence (22.1% vs 53.4%) and rates of unawareness of the diagnosis (60.9% vs 83.8%), treatment (39.1% vs 16.2%), and control (21.2% vs 3.6%), respectively. Similar trends were seen in the secondary analyses. Population changes in lifestyle could have a very large impact on the prevalence and control of hypertension in China. The results support implementation of programs to improve population lifestyles while implementing health services policies to enhance the clinical management of hypertension.

This study explored the effects of mulching straw mat, agricultural carpet, transparent-plastic film and horticultural fabric on nitrification-denitrification, nitrate reductase (NR), nitrite reductase (NiR), ammonium, nitrate and nitrite nitrogen in root-zone soil grown with three-year old apple trees (Malus domestica cv. Starkrimson) during summer and autumn. Results showed that the four treatments decreased nitrification intensity in summer soil, NiR activity in summer-autumn soil and the variation coefficient of nitrification-denitrification intensity and NR in both summer and autumn soil. The treatments increased the denitrification intensity, NR activity, ammonium nitrogen contents in summer-autumn soil and ammonium nitrogen contents in autumn soil. Straw mat treatment increased denitrification intensity and nitrate nitrogen contents in both summer and autumn soil and decreased the activity of NR and NiR in summer soil. The coefficient of variation of nitrification-denitrification intensity and NR activity treated by mulching straw mat was lower than those in the other treatments in both summer and autumn soil. Agricultural carpet increased the NR and NiR activity in summer soil, the nitrate nitrogen contents in summer-autumn soil and the denitrification intensity in autumn soil and decreased denitrification intensity in summer soil. Transparent-plastic film increased the nitrite nitrogen contents in summer soil, the contents of nitrate nitrogen in summer-autumn soil, the nitrification intensity and NiR activity in autumn soil, and decreased nitrate nitrogen contents in summer soil. Horticultural fabric increased denitrification intensity in summer soil, nitrification intensity in summer-autumn and autumn soil and the nitrate nitrogen contents in autumn soil. The four mulching treatments all promoted plant growth. In the four mulching treatments, the new shoot and trunk thickening growth were more under straw mat and horticultural fabric treatments. The four mulching treatments had different effects on nitrate metabolism in summer and autumn soil, but they were able to stabilize the soil nitrate metabolism and transformation. Among the treatments, straw mat had the best stable effect.以3年生新红星苹果树为试验材料,在春季将稻草苫、农用地毯、透明塑料膜和园艺地布覆盖地表,于夏秋季调查根区土壤硝化-反硝化作用、硝酸还原酶(NR)和亚硝酸还原酶(NiR)活性以及铵态氮、硝态氮、亚硝态氮含量和植株生长的变化.结果表明: 4种覆盖处理均降低了夏季土壤硝化强度和夏秋之交的土壤NiR活性,提高了秋季土壤铵态氮含量以及夏秋之交的土壤反硝化强度、NR活性和铵态氮含量,降低了夏秋季土壤硝化强度、反硝化强度和NR活性的变异系数;稻草苫提高了夏季和秋季土壤反硝化强度与硝态氮含量,降低了夏季土壤NR和NiR活性;在4种处理中,稻草苫覆盖的土壤硝化与反硝化强度及NR活性在整个夏秋季的变异系数最低;农用地毯降低了夏季土壤反硝化强度,提高了夏季土壤NR和NiR活性、夏秋之交土壤硝态氮含量和秋季土壤反硝化强度;透明塑料膜降低了夏季土壤硝态氮含量,提高了夏季土壤亚硝态氮含量、夏秋之交土壤硝态氮含量以及秋季土壤硝化强度和NiR活性;园艺地布提高了夏季土壤反硝化强度、夏秋之交和秋季土壤的硝化强度以及秋季土壤硝态氮含量.4种覆盖处理均促进了植株生长,其中稻草苫和园艺地布促进新梢和干径增粗的效果更显著;4种覆盖处理对夏秋季土壤硝酸盐代谢的影响不同,但对土壤硝酸盐代谢与转化都具有稳定作用,其中稻草苫的稳定效果最好.

Loquat is an important commercial specialty fruit tree crop in China, and as a result, there is significant interest in its genetic improvement. Wild loquat, native to China, provides a remarkable genetic resource for breeding improved varieties. Guizhou Province in southwest China contains many natural populations of loquat in its rural areas. In the present study, we analyzed the genetic diversity of native loquat growing throughout Guizhou Province together with wild relatives and domesticated loquat using a set of 20 informative SSR markers. Molecular analysis identified four gene pools, with gene pool I representing cultivated genotypes and gene pool IV containing wild relatives and native surveyed accessions. Approximately 10.8 % of the samples collected from Guizhou Province are feral forms derived from cultivated genotypes, whereas 24.9 % are most closely related to wild species. The remaining 64.3 % of the gene pool is intermediate genotypes derived from spontaneous crosses between wild native forms and cultivated loquat.

From the visual condition, steel corrosion status, chloride content,concrete strength and other aspects, reinforecd concrete structures after electrochemical chloride extraction treatment nearly 10 years were surveyed and detected, and the results showed that the structure surface had a good appearance and no obvious deterioration,the content of chloride ions in concrete was low, the content of chloride ions around rebar areas was far lower than the critical value,the rebar remained in fully passive condition, the electrochemical chloride extraction treatment had no significant influence on the concrete strength, the seal coat on the structure surface was relative complete, but the aging phenomenon such as color alteration, adhesion strength reduction etc. was found on the surface, except for some discoloration and reduced adhesion strength.

What the researchers go in for is to establish models between root architecture (RA) changes and nutrition, mold ideal root architecture of apple trees, improve the nutrient uptake efficiency, and further explore the functional mechanism of nutrient elements during the course of RA construction. The cultivation system of filter paper is utilized to research the effect of nutrient deficiency on the RA of Malus hupehensis (Pump.) Rehd. There may be eight types of RA. In complete Hogland solution, the main type of RA is ”lateral roots clustering in the upper and middle regions of primary root”. With the lack of P, K or Ca, the main type of RA is ”lateral roots clustering in the upper region primary root”, and the ”lateral roots clustering in the upper and middle regions of primary root” types of RA decrease. But with shortage of P, the type of lateral roots clustering in the upper and lower regions of primary root increases, and the type of lateral roots clustering in the middle region of primary root decreases, with the types of RA diversified. Under the condition of K deficiency, the type of no lateral root increases and types of lateral roots clustering in the middle region of primary root decrease, and the percentage of such types as ”no lateral root”, ”lateral roots clustering in the upper region of primary root”, and ”lateral roots clustering in the upper and middle regions of primary root” accounts for 97.9% in all, with the types of RA simplified. With lack of Fe, Mg or Zn, the main type of RA is ”lateral roots clustering in the upper and middle regions of primary root”, but the type of lateral roots evenly-distributed on primary root increases. The main type of RA is ”lateral roots evenly-distributed on primary root”, under the condition of N deficiency, and the types of RA turn out to be diversified. There exists a close relation between nutrient deficiency and RA changes. Owing to various forms of nutrient deficiency, correspondingly different types of RA have been produced.

Eight plant seedlings of citrus species, Citrus tangerina, C. erythrosa, C. chuana, Poncirus trifoliate, C. sinensis x P. trifoliate, C. grandis, C. sinensis and C. vessucosa were used to investigate the effects of drought stress on plant biomass, drought resistance coefficient and leaf hormone (ABA, GA1+3 , ZR, IAA) changes. The results showed that, on the condition of precipitation less than 1200 mm, the biomass of different citrus species reduced obviously, and drought-resistance index and drought resistance showed in order of C. erythrosaC. tangerinaP. trifoliateC. chuanaC. sinensis x P. trifoliateC. grandisC. sinensisC. vessucosa. The leaf ABA contents of the eight species increased whereas GA1+3 , ZR and IAA decreased, under the condition of drought stress. The ratios of ABA/GA1+3 and ABA/ZR in the species of C. erythrosa and C. tangerina increased drastically, yet there was no significant correlation between the ratio of ABA/IAA and the drought tolerance. The drought-resistance index was significantly positively related to the relative content of ABA (P0.01), while significantly negatively related to the relative content of GA1+3. The function to enhance drought resistance by those endogenous hormones in the citrus species showed in order of ABAGA1+3, ZRIAA.

Ascorbic acid (AsA) and sugar levels, together with activities of L-galactono-1,4-lactone dehydrogenase (GalLDH, a key enzyme in AsA biosynthesis in higher plant), AAO, AAP, MDAR and DHAR in fruit of Rosa roxburghii Tratt were measured during development. The result showed that AsA accumulated continually but with a slow, fast and slow accumulating rate in the R. roxburghii fruit during its development, in which the period from the end of June to the early of August was the most important period of AsA accumulation, since the AsA accumulated in this stage accounting for approximately 90% of the final level (Fig.1B). Changes in GalLDH activity coincided with AsA accumulating rate during fruit development (Fig.2B). The extremely significant positive correlation existed between the GalLDH activity and AsA accumulating rate (r(2)=0.783**) (Fig.3). Transitory and low activities of AAO and AAP in the fruit were detected in the initial stage of development (Table 1), suggesting that little AsA degraded by the activities of the two oxidative enzymes during the whole development. This data elucidated, at least in part, the reason for high accumulation of AsA in the R. roxburghii fruit. Furthermore, no activity of MDAR or DHAR in the fruit was detected during the whole development, implying that the two enzymes are not key factors for contribution of AsA level. No correlation was found between AsA content and sugar contents in the R. roxburghii fruit.