城-镇-乡人口教育差距的演变及影响机制

在城乡一体化的过程中,以平均受教育水平测量的城乡人口教育差距,并没有出现库兹涅茨倒U型发展,乡村、县镇与城市之间的差距都在不断扩大。对近20年间差距演变的过程进行分析表明,乡村和县镇人口平均受教育水平的增长速度始终低于城市,尤其是县镇区域几乎没有增长。通过对主要影响因素及作用机制的理论分析和实证检验,研究发现,经济发展水平的提高并没有促使已经存在的差距自然消弥,城乡两个被分割的群体通过显性渠道与隐性渠道不断地文化教育再生产是差距存在和扩大的社会基础;高中阶段教育投入的增加更多是促进了城镇人口受教育水平的提高,初中阶段教育投入城乡差距的扩大直接导致人口受教育程度差距的扩大,而小学阶段教育投入城乡差距没有显示出统计上显著的影响;非户籍人口流动造成城乡人口结构的异质化,并进而扩大城乡常住人口受教育程度的差距;户籍人口迁入对城市和县镇人口受教育程度都有提升作用,迁出在抵消迁入的提升作用后,仍然导致城市与县镇之间教育差距的扩大。     

孝感城区中老年对慢性病及社区管理现状认知情况的调查研究

目的:调查孝感城区中老年对慢性病及其社区管理现状认知情况。方法:选择2010年7月至2015年7月在孝感城区3个社区的500名中老年人作为研究对象,利用自拟调查问卷对所有受试者进行数据调查,分析孝感城区中老年对慢性病的认知情况,及对慢性病社区管理现状的认知情况,分析影响慢性病认知的因素。结果:在慢性病种类中,孝感城区中老年人对于高血压和糖尿病,及风湿性关节炎与慢性支气管炎的认知率较高,而对于癌症、偏瘫及血栓的认知率较低,差异有统计学意义(P0.05)。在慢性病的危险因素中,孝感城区中老年人对于缺乏锻炼、吸烟及膳食不合理的认知率明显较高,而对于酗酒、缺乏保健知识及悲观情绪的认知率明显较低,差异有统计学意义(P0.05)。在慢性病社区管理现状上,孝感城区中老年对于指导其改变生活习惯的认知率较高,为62.00%,而在进行三级预防、强化慢性病自我管理、定期举办慢性病专题讲座以及建立社区卫生的信息服务平台等方面的认知率明显较低,分别为22.40%、36.80%、42.20%及21.80%,差异有统计学意义(P0.05)。Logistic分析显示,文化程度低、经济收入低、未患慢性病及年龄≥60岁均为慢性病认知的危险因素。结论:孝感城区中老年对慢性病及其社区管理现状认知仍存在一定的不足,相关社区卫生管理部门应针对问题的影响因素,积极采取措施,改善社区管理现状。     

Combined metabolomics and proteomics reveals hypoxia as a cause of lower productivity on scale‐up to a 5000‐liter CHO bioprocess

Large‐scale bioprocessing is key to the successful manufacturing of a biopharmaceutical. However, cell viability and productivity are often lower in the scale‐up from laboratory to production. In this study, we analyzed CHO cells, which showed lower percent viabilities and productivity in a 5‐KL production scale bioreactor compared to a 20‐L bench‐top scale under seemingly identical process parameters. An increase in copper concentration in the media from 0.02 µM to 0.4 µM led to a doubling of percent viability in the production scale albeit still at a lower level than the bench‐top scale. Combined metabolomics and proteomics revealed the increased copper reduced the presence of reactive oxygen species (ROS) in the 5‐KL scale process. The reduction in oxidative stress was supported by the increased level of glutathione peroxidase in the lower copper level condition. The excess ROS was shown to be due to hypoxia (intermittent), as evidenced by the reduction in fibronectin with increased copper. The 20‐L scale showed much less hypoxia and thus less excess ROS generation, resulting in little to no impact to productivity with the increased copper in the media. The study illustrates the power of 'Omics in aiding in the understanding of biological processes in biopharmaceutical production.     

The extent of shifts in vegetation phenology between rural and urban areas within a human‐dominated region

Urbanization is one of the major environmental challenges facing the world today. One of its particularly pressing effects is alterations to local and regional climate through, for example, the Urban Heat Island. Such changes in conditions are likely to have an impact on the phenology of urban vegetation, which will have knock‐on implications for the role that urban green infrastructure can play in delivering multiple ecosystem services. Here, in a human‐dominated region, we undertake an explicit comparison of vegetation phenology between urban and rural zones. Using satellite‐derived MODIS‐EVI data from the first decade of the 20th century, we extract metrics of vegetation phenology (date of start of growing season, date of end of growing season, and length of season) for Britain's 15 largest cities and their rural surrounds. On average, urban areas experienced a growing season 8.8 days longer than surrounding rural zones. As would be expected, there was a significant decline in growing season length with latitude (by 3.4 and 2.4 days/degree latitude in rural and urban areas respectively). Although there is considerable variability in how phenology in urban and rural areas differs across our study cities, we found no evidence that built urban form influences the start, end, or length of the growing season. However, the difference in the length of the growing season between rural and urban areas was significantly negatively associated with the mean disposable household income for a city. Vegetation in urban areas deliver many ecosystem services such as temperature mitigation, pollution removal, carbon uptake and storage, the provision of amenity value for humans and habitat for biodiversity. Given the rapid pace of urbanization and ongoing climate change, understanding how vegetation phenology will alter in the future is important if we wish to be able to manage urban greenspaces effectively.     

Coping with potential bi‐parental inbreeding: limited pollen and seed dispersal and large genets in the dioecious marine angiosperm Thalassia testudinum

The high prevalence of dioecy in marine angiosperms or seagrasses (>50% of all species) is thought to enforce cross‐fertilization. However, seagrasses are clonal plants, and they may still be subject to sibling‐mating or bi‐parental inbreeding if the genetic neighborhood is smaller than the size of the genets. We tested this by determining the genetic neighborhoods of the dioecious seagrass Thalassia testudinum at two sites (Back‐Reef and Mid‐Lagoon) in Puerto Morelos Reef Lagoon, Mexico, by measuring dispersal of pollen and seeds in situ, and by fine‐scale spatial autocorrelation analysis with eight polymorphic microsatellite DNA markers. Prevalence of inbreeding was verified by estimating pairwise kinship coefficients; and by analysing the genotypes of seedlings grown from seeds in mesocosms. Average dispersal of pollen was 0.3–1.6 m (max. 4.8 m) and of seeds was 0.3–0.4 m (max. 1.8 m), resulting in a neighborhood area of 7.4 m² (range 3.4–11.4 m²) at Back‐Reef and 1.9 (range 1.87–1.92 m²) at Mid‐Lagoon. Neighborhood area (Na) derived from spatial autocorrelation was 0.1–20.5 m² at Back‐Reef and 0.1–16.9 m² at Mid‐Lagoon. Maximal extensions of the genets, in 19 × 30 m plots, were 19.2 m (median 7.5 m) and 10.8 m (median 4.8 m) at Back‐Reef and Mid‐Lagoon. There was no indication of deficit or excess of heterozygotes nor were coefficients of inbreeding (F_IS) significant. The seedlings did not show statistically significant deficit of heterozygotes (except for 1 locus at Back‐Reef). Contrary to our expectations, we did not find evidence of bi‐parental inbreeding in this dioecious seagrass with large genets but small genetic neighborhoods. Proposed mechanisms to avoid bi‐parental inbreeding are possible selection against homozygotes during fecundation or ovule development. Additionally, the genets grew highly dispersed (aggregation index Ac was 0.09 and 0.10 for Back‐Reef and Mid‐Lagoon, respectively); such highly dispersed guerrilla‐like clonal growth form likely increases the probability of crossing between different potentially unrelated genets.     

Genetic evidence for prevalence of alloparental care in a socially monogamous biparental cichlid fish,Perissodus microlepis,from Lake Tanganyika supports the “selfish shepherd effect” hypothesis

Alloparental care – care for unrelated young – is rare in animals, and its ecological or evolutionary advantages or, alternative maladaptive nature, remain unclear. We investigate alloparental care in the socially monogamous cichlid fish Perissodus microlepis from Lake Tanganyika that exhibits bi‐parental care. In a genetic parentage analysis, we discovered a surprisingly high percentage of alloparental care represented by brood mixing, extra‐pair paternity and extra‐pair maternity in all broods that we investigated. The percentage of nondescendant juveniles of other parents, i.e., brood mixing, ranged from 5% to 57% (mean = 28%). The distribution of genetic parentage also suggests that this socially monogamous species has, in fact, polygamous mating system. The prevalence of genetically mixed broods can be best explained by two, not mutually exclusive hypotheses on farming‐out and fostering behaviors. In the majority of broods, the sizes of the parents’ own (descendant) offspring were significantly larger than those of the adopted (nondescendant) juveniles, supporting the ‘selfish shepherd effect’ hypothesis, i.e., that foster parents preferentially accept unrelated “smaller or not larger” young since this would tend to lower the predation risks for their own larger offspring. There was also a tendency for larger parents particularly mothers, more so than smaller parents, to care predominantly for their own offspring. Larger parents might be better at defending against cuckoldry and having foreign young dumped into their broods through farming‐out behavior. This result might argue for maladaptive effects of allopatric care for the foster parents that only larger and possibly more experienced pairs can guard against. It needs to be determined why, apparently, the ability to recognize one's own young has not evolved in this species.     

Ecological role of vertebrate scavengers in urban ecosystems in the UK

Recent research has demonstrated how scavenging, the act of consuming dead animals, plays a key role in ecosystem structure, functioning, and stability. A growing number of studies suggest that vertebrate scavengers also provide key ecosystem services, the benefits humans gain from the natural world, particularly in the removal of carcasses from the environment. An increasing proportion of the human population is now residing in cities and towns, many of which, despite being highly altered environments, contain significant wildlife populations, and so animal carcasses. Indeed, non‐predation fatalities may be higher within urban than natural environments. Despite this, the fate of carcasses in urban environments and the role vertebrate scavengers play in their removal have not been determined. In this study, we quantify the role of vertebrate scavengers in urban environments in three towns in the UK. Using experimentally deployed rat carcasses and rapid fire motion‐triggered cameras, we determined which species were scavenging and how removal of carcass biomass was partitioned between them. Of the 63 experimental carcasses deployed, vertebrate scavenger activity was detected at 67%. There was a significantly greater depletion in carcass biomass in the presence (mean loss of 194 g) than absence (mean loss of 14 g) of scavengers. Scavenger activity was restricted to three species, Carrion crows Corvus corone, Eurasian magpies Pica pica, and European red foxes Vulpes vulpes. From behavioral analysis, we estimated that a maximum of 73% of the carcass biomass was removed by vertebrate scavengers. Despite having low species richness, the urban scavenger community in our urban study system removed a similar proportion of carcasses to those reported in more pristine environments. Vertebrate scavengers are providing a key urban ecosystem service in terms of carcass removal. This service is, however, often overlooked, and the species that provide it are among some of the most disliked and persecuted.     

Phenological growth stages of nashi tree (Pyrus pyrifolia): codification and description according to the BBCH scale

The phenological growth stages of nashi tree were firstly described here using the BBCH scale. Based on this general scale, nashi phenology showed 8 of the 10 principal stages (0–9): bud, leaf and shoot development, inflorescence emergence, flowering, fruit development, fruit maturity and senescence. A schematic representation of the chronological progression of principal growth stages of nashi is also shown. The codification of the different growth stages is important for correct timing of general orchard management, particularly for disease and pest management. Besides, it will help farmers to efficiently schedule and manage nashi cultivation, as well as to improve knowledge dissemination among scientists around the World.     

A scale‐down mimic for mapping the process performance of centrifugation,depth and sterile filtration

In the production of biopharmaceuticals disk‐stack centrifugation is widely used as a harvest step for the removal of cells and cellular debris. Depth filters followed by sterile filters are often then employed to remove residual solids remaining in the centrate. Process development of centrifugation is usually conducted at pilot‐scale so as to mimic the commercial scale equipment but this method requires large quantities of cell culture and significant levels of effort for successful characterization. A scale‐down approach based upon the use of a shear device and a bench‐top centrifuge has been extended in this work towards a preparative methodology that successfully predicts the performance of the continuous centrifuge and polishing filters. The use of this methodology allows the effects of cell culture conditions and large‐scale centrifugal process parameters on subsequent filtration performance to be assessed at an early stage of process development where material availability is limited. Biotechnol. Bioeng. 2016;113: 1934–1941. © 2016 The Authors. Biotechnology and Bioengineering Published by Wiley Periodicals, Inc.