我国现阶段农村土地制度探析

农地制度是农村经济制度中最基础性的制度安排,从根本上制约着农业经济的效率。对现阶段中国农地制度进行系统深入的研究,将有助于我们正确认识现阶段中国农地制度的合理性及缺陷,为现阶段中国农地制度的调整和改革提供决策参考,从而为推动“三农问题”的解决做出贡献

湖南单子叶植物1新记录科——闭鞘姜科及其分类学研究

2017~2018在湖南省涔天河湿地公园进行植物资源调查,发现了若干湖南新记录植物,该文对湖南单子叶植物1新记录科——闭鞘姜科(Costaceae Nakai)进行报道,含1新记录属——大唇闭鞘姜属(Hellenia Retzius),1新记录种——闭鞘姜[Hellenia speciosa (J.Koenig)Govaerts]。通过查阅相关文献资料,对闭鞘姜科的属级分类单元变化及闭鞘姜新的接受名进行概述。闭鞘姜科主要分布在热带地区,在湖南的发现为湖南的生物多样性和植物区系研究提供了重要的基础资料

轻小型无人机遥感及其行业应用进展

无人机是低空领域准确、灵活、高效获取多种类型高分辨率遥感数据的重要载体,无人机遥感技术在行业应用创新和管理部门科学决策之间构筑起信息沟通的关键桥梁。随着科技的进步、大数据时代的来临,无人机遥感系统的硬件设备、信息提取方法都取得了飞速的发展;同时其在国民经济主要行业领域的应用也面临着前所未有的机遇和挑战。论文首先介绍了无人机遥感系统的硬件研发进展,并指出轻小型、高精度、标准化与集成化是未来无人机遥感系统发展的总体趋势。其次,详细介绍了目前轻小型无人机遥感应用在农业、林草业、电力、测绘、大气探测和地质灾害等行业的应用现状,指出实现无人机多源遥感数据获取、融合、分析和提取的综合平台是未来轻小型无人机在民用领域行业应用创新的关键所在。最后,针对载荷与飞行平台的一体化集成应用、无人机组网作业、海量数据管理和信息自动化提取等发展趋势提出了几点思考。轻小型无人机遥感在国民经济各行业应用的普及化和标准化,将有助于国家和区域社会经济的健康发展

Aripiprazole versus other atypical antipsychotics for schizophrenia

BACKGROUND: In most western industrialised countries, second generation (atypical) antipsychotics are recommended as first line drug treatments for people with schizophrenia. In this review we specifically examine how the efficacy and tolerability of one such agent - aripiprazole - differs from that of other comparable second generation antipsychotics. OBJECTIVES: To evaluate the effects of aripiprazole compared with other atypical antipsychotics for people with schizophrenia and schizophrenia-like psychoses. SEARCH METHODS: We searched the Cochrane Schizophrenia Group Trials Register (November 2011), inspected references of all identified studies for further trials, and contacted relevant pharmaceutical companies, drug approval agencies and authors of trials for additional information. SELECTION CRITERIA: We included all randomised clinical trials (RCTs) comparing aripiprazole (oral) with oral and parenteral forms of amisulpride, clozapine, olanzapine, quetiapine, risperidone, sertindole, ziprasidone or zotepine for people with schizophrenia or schizophrenia-like psychoses. DATA COLLECTION AND ANALYSIS: We extracted data independently. For dichotomous data we calculated risk ratios (RR) and their 95% confidence intervals (CI) on an intention-to-treat basis based on a random-effects model. Where possible, we calculated illustrative comparative risks for primary outcomes. For continuous data, we calculated mean differences (MD), again based on a random-effects model. We assessed risk of bias for each included study. MAIN RESULTS: We included 12 trials involving 6389 patients. Aripiprazole was compared to olanzapine, risperidone and ziprasidone. All trials were sponsored by an interested drug manufacturer. The overall number of participants leaving studies early was 30% to 40%, limiting validity (no differences between groups).When compared with olanzapine no differences were apparent for global state (no clinically important change: n = 703, 1 RCT, RR short-term 1.00 95% CI 0.81 to 1.22; n = 317, 1 RCT, RR medium-term 1.08 95% CI 0.95 to 1.22) but mental state tended to favour olanzapine (n = 1360, 3 RCTs, MD total Positive and Negative Syndrome Scale (PANSS) 4.68 95% CI 2.21 to 7.16). There was no significant difference in extrapyramidal symptoms (n = 529, 2 RCTs, RR 0.99 95% CI 0.62 to 1.59) but fewer in the aripiprazole group had increased cholesterol levels (n = 223, 1 RCT, RR 0.32 95% CI 0.19 to 0.54) or weight gain of 7% or more of total body weight (n = 1095, 3 RCTs, RR 0.39 95% CI 0.28 to 0.54).When compared with risperidone, aripiprazole showed no advantage in terms of global state (n = 384, 2 RCTs, RR no important improvement 1.14 95% CI 0.81 to 1.60) or mental state (n = 372, 2 RCTs, MD total PANSS 1.50 95% CI -2.96 to 5.96).One study compared aripiprazole with ziprasidone (n = 247) and both the groups reported similar change in the global state (n = 247, 1 RCT, MD average change in Clinical Global Impression-Severity (CGI-S) score -0.03 95% CI -0.28 to 0.22) and mental state (n = 247, 1 RCT, MD change PANSS -3.00 95% CI -7.29 to 1.29).When compared with any one of several new generation antipsychotic drugs the aripiprazole group showed improvement in global state in energy (n = 523, 1 RCT, RR 0.69 95% CI 0.56 to 0.84), mood (n = 523, 1 RCT, RR 0.77 95% CI 0.65 to 0.92), negative symptoms (n = 523, 1 RCT, RR 0.82 95% CI 0.68 to 0.99), somnolence (n = 523, 1 RCT, RR 0.80 95% CI 0.69 to 0.93) and weight gain (n = 523, 1 RCT, RR 0.84 95% CI 0.76 to 0.94). Significantly more people given aripiprazole reported symptoms of nausea (n = 2881, 3 RCTs, RR 3.13 95% CI 2.12 to 4.61) but weight gain (7% or more of total body weight) was less common in people allocated aripiprazole (n = 330, 1 RCT, RR 0.35 95% CI 0.19 to 0.64). Aripiprazole may have value in aggression but data are limited. This will be the focus of another review. AUTHORS' CONCLUSIONS: Information on all comparisons are of limited quality, are incomplete and problematic to apply clinically. Aripiprazole is an antipsychotic drug with a variant but not absent adverse effect profile. Long-term data are sparse and there is considerable scope for another update of this review as new data emerges from the many Chinese studies as well as from ongoing larger, independent pragmatic trials