社会学视野中的富人“超生”

当前我国的富人“超生”现象较为复杂;与传统的农民“超生”相比较,它呈现出职业分布和空间分布的普遍性、“超生”动机的“高级化”与手段的多样化等新的特点。它的形成有多方面的原因,并且带来人口与社会方面的多重后果。为此,有必要坚持和谐社会理念,加强对富人“超生”问题的治理。

田间玉米产生“香蕉穗”及“超生”的原因及防治措施

分别介绍了田间玉米"香蕉穗"及"超生"的症状表现、产生原因及防治措施,供参考。

“超生贵族”现象产生的原因及其规制

一些名人和富人凭借其独特的社会地位和丰厚的财力而违背计划生育政策实行超生的现象。“超生贵族”现象的存在是引起我国低生育水平反弹的因素之一，也是对计划生育基本国策的冲击和对《人口与计划生育法》的挑战，更重要的是它体现了社会的不公平。产生这一现象的因素颇多。人口与计划生育管理部门要加强对“超生贵族”的危害性认识，各部门齐抓共管，不断完善我国各地的社会抚养费的征收方法，合理引导，积极遏制“超生贵族”现象。

中西部农村地区人口计划生育调查之分析

利用有关数据对中国中西部农村地区的人口“计划外生育”(超生)现象进行研究。研究发现,社会经济基础、生育文化和计划生育政策强度是影响不同地区“计划外生育”的主要因素。研究还发现,这些地区的人口生育水平实际上已经处于较低的水平。事实上,“计划外生育”或“超生”现象与计划生育政策的不同界定标准有很大关系,这与上世纪八、九十年代出现的“超生”现象不具有可比性。

A super-resolution reconstruction algorithm for mural images based on improved generative adversarial network

In order to solve the problem of the lack of ornamental value and research value of ancient mural paintings due to low resolution and fuzzy texture details,a super resolution(SR)method based on generative adduction network(GAN)was proposed.This method reconstructed the detail texture of mural image better.Firstly,in view of the insufficient utilization of shallow image features,information distillation blocks(IDB)were introduced to extract shallow image features and enhance the output results of the network behind.Secondly,residual dense blocks with residual scaling and feature fusion(RRDB-Fs)were used to extract deep image features,which removed the BN layer in the residual block that affected the quality of image generation,and improved the training speed of the network.Furthermore,local feature fusion and global feature fusion were applied in the generation network,and the features of different levels were merged together adaptively,so that the reconstructed image contained rich details.Finally,in calculating the perceptual loss,the brightness consistency between the reconstructed fresco and the original fresco was enhanced by using the features before activation,while avoiding artificial interference.The experimental results showed that the peak signal-to-noise ratio and structural similarity metrics were improved compared with other algorithms,with an improvement of 0.512 dB-3.016 dB in peak signal-to-noise ratio and 0.009-0.089 in structural similarity,and the proposed method had better visual effects.

农村计划生育工作难以推行的经济学分析

计划生育工作是保持人口与经济相协调、促进我国可持续发展的重要举措。在我国现有的社会条件下,农村家庭"超生"的成本较低、而收益较高,导致计划生育工作难以推行。单纯的罚款和计划生育工作并不能完全有效地从根本上解决与遏止农村家庭"超生"的问题。政府要多管齐下,营造一个良好的农村社会经济环境,加大对人力资本投资,加快社会保障建设,促进现代农业发展、以更好地完善我国计划生育政策。

Physiology and Ultrastructure of Azolla imbricata as Affected by Hg 2+ and Cd 2+ Toxicity

The toxic effects of different gradient concentrations of Hg2+ and Cd2+ on chlorophyll content, chlorophyll a/b value, photosynthetic O-2 evolution, respiration rate, anti-oxidase system (superoxide dismulase (SOD), catalase (CAT), peroxidase (POD)) and ultrastructure of the cells of Azolla imbricata (Roxb.) Nakai were studied. The results showed that with Hg2+ and Cd2+ increase, chlorophyll content and chlorophyll a/b value, photosynthetic O-2 evolution decreased drastically; respiration rate peaked at 2 mg/L pollutant and declined afterwards. The activities of SOD, CAT and POD increased first and decreased afterwards except the activity of POD, which decreased with the increasing of Cd2+ concentration. Ultrastructural observation showed that the extent of ultrastructural damage was much more serious with higher pollutant concentration and longer time of stress. This resulted in swelling of chloroplast, disruption and disappearance of chloroplast membrane and disintegration of chloroplasts; swelling of cristae of mitochondria, deformation and vacuolization of mitochondria; condensation of chromatin in nucleus, dispersion of nucleolus and disruption of nuclear membrane. The experimental results showed: (1) Hg2+ and Cd2+ pollution not only destroyed physiological activities, but also caused irreversible damage to its ultrastructure, thus leading the cells to death; (2) With increase in the stress of Hg2+ and Cd2+, ultrastructural damage was related to the changes of plant physiology; (3) The toxic symptoms of plant showed an evident correlation between dose and effect; (4) The toxicity of Cd2+ on A. imbricata is heavier than that of Hg2+ under the same treatment time and concentration. The lethal concentration of Hg2+ to A. imbricata ranged from 3.5 to 4 mg/L, and that of Cd2+ ranged from 3 to 3.5 mg/L. The damage of cell ultrastructure on Anabaena azollae Strasburger was observed. The results indicated that tolerance of Azolla imbricata for Hg2+ and Cd2+ was higher than that of A. imbricata.

Development and Ultrastructure of the Phloem Ganglion in Bamboo Node

The development, cytological characters and ultrastructure of phloem ganglion in the nodal region of Phyllostachys edulis (Carr.) H. de Lehaie, a most economically important bamboo, were investigated and the possible physiological function of this special structure was proposed. The phloem ganglion derived directly from procambium is situated at the sites where the vascular bundle forks and is present in pairs. The phloem ganglion is spindle_like in appearance and usually consists of 4 to 6 layers. Two kinds of cells in the ganglion could be distinguished. In the middle, there are two layers of filiform cells with pointed ends so that there are no normal sieve plates. Nevertheless, there are many pits on the lateral wall of the filiform cells. The other type of cells located at both ends of the spindle which possess an intermediate form between the filiform cell and the normal sieve tube. The walls of these cells towards the filiform cells are strongly convex forming a special sieve plate. Ultrastructure study showed that cells in the ganglion are connected by enriched plasmodesma. During early differentiation, the paramural body and the ingrowth of cell wall could be observed. It indicates that the cells of phloem ganglion have the character of transfer cells. The organelles in the mature cells are mainly plastids with abundant accumulation of proteins of crystalline structure. The above_mentioned results suggest that the physiological function of the phloem ganglion is closely related with substance transport.

Ultrastructural Study of Secondary Wall Formation in the Stem Fiber of Phyllostachys pubescens

Ultrastructural changes in secondary wall formation of Phyllostachys pubescens Mazel fiber were investigated with transmission electron microscopy. Fiber developed initially with the elongation of cells containing ribosomes, mitochondria and Golgi bodies in the dense cytoplasm. During the wall thickening, the number of rough endoplasmic reticulum and Golgi bodies increased apparently. There were two kinds of Golgi vesicles, together with the ones from endoplasmic reticulum formed transport vesicles. Many microtubules were arranged parallel to the long axis of the cell adjacent to the plasmalemma. Along with the further development of fiber, polylamellate structure of the secondary wall appeared, with concurrent agglutination of chromatin in the nucleus, swelling and disintegration of organelles, while cortical microtubules were still arranged neatly against the inner side of plasmalemma. Lomasomes could be observed between the wall and plasmalemma. The results indicated that the organelles, such as Golgi bodies together with small vesicles, rough endoplasmic reticulum and lomasomes, played the key role in the thickening and lignification of the secondary wall of bamboo fiber, though cortical microtubules were correlative with the process as well.

Effects of the profile of a supercavitating vehicle's front-end on supercavity generation

The authors designed three different front profiles for supercavitating vehicles based on cavity theory and the Granville streamlined equation are designed. Experiments were done using these front profiles in the Northwestern Polytechnical University high-speed water tunnel. The experiments indicated that the critical volume of gas required for supercavitation is affected by the axial distribution of the front-end＇s slope. The experimental data showed critical gas flow rates required for the three designs were less than rood-l, with the greatest decrease 24%. The experimental results also showed the supercavitation generation speeds of the models were faster than mod-1 by up to 32.4%. This verifies that the front profile of a supercaviting vehicle effects supercavity generation speed and critical gas flow rates. The smaller the changes in axial distribution of pressure, the higher the supercavity generation speed. The smaller the changes in curvature distribution of axial, the smaller the critical gas flow rates.

Effect of Microbial Inoculum Fertilizer on the Growth and Yield of Super Hybrid Rice

The research designed four application quantities of 0, 2 250, 4 500 and 6 750 g/hm2 based on Liangyou No. 959 to explore the effects of microbial inocu- lure fertilizer on growth and yield of super hybrid rice. The results indicate that the treatment with traditional fertilizers and 4 500 g/hm2 HYT microbial inoculum fertilizer performed the best, where average number of tiller was 2.4 more than that of the control; the number of effective ear was 11.05% higher; yield increased by 10.3%. These have demonstrated that microbial inoculum fertilizer is of great value in pro- motion on super hybrid rice production.

Responses of Picoplankton to Nutrient Perturbation in the South China Sea, with Special Reference to the Coast-wards Distribution of Prochlorococcus

Responses of Prochlorococcus (Pro), Synechococcus (Syn), pico-eukaryotes (Euk) and heterotrophic bacteria (Bact) in pelagic marine ecosystems to external nutrient perturbations were examined using nitrogen- (N), phosphorus- (P), iron- (Fe), and cobalt- (Co) enriched incubations in the South China Sea in November 1997. Variations in abundance of the 4 groups of microorganism and cellular pigment content of the autotrophs during incubation were followed by flow-cytometric measurements for seven days. During the incubation, Syn and Euk showed a relatively higher demand on Fe and N, while Pro required higher levels of Co and P. The Fe was inadequate for all the organisms in the deep euphotic zone (75 m) of the study area. The experimental results also implied that biological interaction among the organisms played a role in the community structure shift during the incubation. It seemed that besides the effects of temperature, there are some other physical and chemical limitations as well as impacts from biological interactions on Pro distribution in coast waters.

Study on the Ultrastructural of Oogenesis of Bullacta exarata

The ultrastructure of oogenesis of Bullacta exarata was studied with transmission electron microscope.The result showed that the oogenesis of Bullacta exarata could be divided into four stages,for example,oogonium,early vitellogenic oocyte,mid vitellogenic oocyte and end vitellogenic oocyte.Besides a large and round nucleus,oogonium mainly contains mitochondria,sacs of golgi and microvillie appears in this stage.At the early stage of vitellogenesis,the organelles are developed,and a great deal of nuages like materials appear in oocyte cytoplasm.At the mid stage of vitellogenesis,the nucleus forms pseudopodia liked extension.The organelles including mitochondria,golgi complex and endoplasmic reticulum are well developed,and lots of yolk granule and lipid droplet are formed in the cytoplasm.The exchange of material between oocytes and follicle cells is intense in this stage.At the end stage of vitellogenesis,the oocytes contain fewer numbers of the organelles.The changes of structure and significance in oocytes,and the exchange of material between oocytes and follicle cells are also discussed.

Prospects for Study on High-yielding Cultivation Techniques of Super Hybrid Rice

Great progresses have been made in super hybrid rice in China. From the perspectives of dry matter production, nutrient absorption, sink and source, pho-tosynthesis, graln fiI ing and roots, the eco-physioIogical characteristics and high-yielding cuItivation techniques of super hybrid rice in China were discussed. In addi-tion, the probIems that restricted the high and stabIe yielding of super hybrid rice were analyzed, and the deveIopment directions of high-yielding cuItivation techniques for super hybrid rice were also discussed.

Importance of Percutaneous Radiofrequency Ablation for Recurrent Hepatocellular Carcinoma

Objective: To study the importance of percutaneous radiofrequency ablation (PRFA) guided by ultrasound for inoperable recurrent hepatocellular carcinoma.Methods: Forty-seven patients with inoperable recurrent hepatocellular carcinoma underwent percutaneous radiofrequency ablation (PRFA) under ultrasond between October 1999 and July 2001. Twenty-four patients had single recurrent tumor and 23 patients had multiple lesions. Twelve patients had single lesion with less than 3.5 cm in diameter. All patients were followed up to examine the value of AFP, MRI or CT after PRFA. Kaplan-Meier estimation was used to analyze the survival rate.Results: The 1-, 2- and 3-year survival rate in single lesion group was 65.2%, 37.5% and 37.5% respectively. The survival rate of 1 and 2 years was 41.7% and 19.5% in the multiple lesions group. The 1-, 2-and 3-year survival rate in single lesion groups with less than 3.5 cm in diameter was 83.3%, 51.4% and 51.4% respectively.Conclusion: PRFA is one of the important comprehensive methods for recurrent hepatocellular carcinoma. According to the size, number and recurrent time, PRFA can be performed separately or combined with transcatheter arterial chemoembolization for inoperable recurrent hepatocellular carcinoma. This method can control the recurrence and increase the survival rate effectively. Key words recurrence - hepatocellular cacinoma - radiofrequency ablation

Optimization of Supercritical Carbon dioxide Extraction of Ginger Essential Oil by Response Surface Method

[Objective] Ginger essential oil （GEO） is widely used in food production and medical field in recent years due to its prominent biological functions, and this study was conducted to obtain high-quality and high-purity ginger essential oil from the fresh ginger. [Method] GEO was extracted from ginger roots by supercritical fluid extraction （SFE） method. The effects of flow rate of CO2, mesh size of ginger powder and volume of entrainer were investigated by single-factor experiments and response surface method. The content and extraction rate of 6-gingerol represented the extraction index of GEO. [Result] The conditions were optimized as follows： flow rate of CO2 at 25 L/h, mesh size of ginger power of 80 mesh, and volume of anhydrous ethanol as entrainer of 92.46 ml. The optimal extraction rate of 6-gingerol was 3.21%, which was predicted by RSM. [Conclusion] The optimal process of supercritical carbon dioxide extraction of ginger essential oil was identified by singlefactor experiments and response surface method. The present study provides a satisfactory method for purifying GEO from ginger for industrial purpose.

Effects of Tiller-inhibitor on Growth and Yield Formation of Super Early Hybrid Rice Jinyou458

[Objective]The paper was to study the effect of tiller-inhibitor on the growth and yield formation of super early rice Jinyou 458.[Method] Two treatments including spraying tiller-inhibitor（TI） and spraying water（CK） at the SN-n stage were set in the test,the effect of tiller-inhibitor on yield and its components,leaf and plant morphology,field microclimate at booting stage and quality characteristics of rice population were studied.[Result] Spraying tiller-inhibitor could effectively reduce the occurrence of invalid and inefficient tillers,increase the proportion of high effective tillers（tiller with 4 or more leaves） in tiller composition at the maximal tiller stage.The panicle length,spikelets per panicle,spikelets density,number of secondary branches and the secondary spikelets,seed setting rate of rice plant sprayed with tiller-inhibitor were significantly higher than CK.Meanwhile,spraying tiller-inhibitor could increase plant height,biomass weight and leaf area index of rice population during middle and late stages of rice growing,improve the leaf temperature of top three leaves and the light transmittance of rice population at the booting stage,increase the leaf SPAD value,thus enhance photosynthetic capacity of rice plants.It also showed the characteristics of elongating the internode of rice plant and decreasing the stem thickness,etc.[Conclusion] The panicle-bearing rate of stems and tillers,effective panicles,spikelets per panicle,seed setting rate and 1 000-grain weight had coordinately increased after spraying tiller-inhibitor,thus increased the yield.

Effects of Weak Light on the Ultrastructural Variations of Phloem Tissues in Source Leaves of Three-Year-Old Nectarine Trees(Prunus persica L.var. nectarina Ait.)

Leaves from three_year_old solar greenhouse nectarine trees ( Prunus persica L. var. nectarina Ait. “Zao Hong Yan”) were used as materials in this study. It was the first time that the ultrastructural characteristics of phloem tissues of source leaves were observed and compared in normal and weak light intensities using the transmission electron microscopy. Results showed that the average diameters of companion cells (CC) and sieve elements (SE) of all kinds of veins were bigger in normal than that in weak light intensity, indicating that light could influence the cell development and growth. Dense cytoplasm with abundant mitochondria, endoplasmic reticulums, multivesicular bodies, vesicles and plastids were observed in normal light intensity. On the contrary, CC with small vacuolar structures and few mitochondrias, endoplasmic reticulums were shown in weak light. Misalignment of grana thylakoid margins of nectarine leaves also was seen in weak light. The sieve pores of SEs were obstructed in weak light. Chloroplasts with numerous starch grains and few mitochondrias were noticed in the mesophyll cell (MES) surrounding the bundle sheath in weak light. The storage of starch grains appeared to result from an unbalance between photosynthate production and export of photosynthates. This observation provided a strong support to the point that most leaves export the most of assimilates in the light time. Plasmodesmal densities between SE/CC, CC/PP (phloem parenchyma cell), PP/PP and PP/BSC (bundle_sheath cell) decreased in weak light. Plasmodesmata were observed between CC/SE (NS) (nacreous_walled sieve element), PP/BSC in branch veins in normal light intensity, but not in weak light. Thus apoplasmic pathway may be the main mode of transport of assimilates in weak light, however symplasmic pathway may be the main mode of transport of assimilates in normal light intensity. These results demonstrated that the solar greenhouse nectarine trees could be adapted to the weak light via the ultrastructure variation of phloem tissues of the source leaves.

The Super-population Bridges the Habitat Diversity and Biodiversity

There is another way for new species to invade former settlers＇ habitats and successfully settle there; it is demonstrated that the su- per-population, which plays a key role in changing the world-wide environment, can create many new microhabitats in the old habitat, it is these new microhabitats that make new species easily come into the old habitat and settle there without fierce competition with former settlers. In other words, the super-population lead to the differentiation of the worldwide environment, lead to the environmental diversity in the biosphere. Through the differentiation of the environment the super-population produces many new microhabitats for new species, the appearance of many new microhabitats make it possible for new species to coexist with former settlers in the biosphere. The cqexistence of new species with former settlers or with new species＇ ＂ancestors＂ results in the increaseing in the biodiversity of the biosphere. The super-population is the founder of many new environments on the earth, it bridges the habitat diversity and the biodiversity. Now It is easy to explain the phenomenon that new species sometimes coexist with former settlers and even depend on former settlers in the biosphere rather than fierce competition between them.