学科研学的学理基础与课程范式研究

就现阶段研学课程开展的总体情况而言,普遍存在“只游不学”或“重游轻学”现象,学科研学作为履行立德树人教育使命必不可少的活动形式之一,有其自身的学理基础和课程规范,就其科学内涵、本质属性和基本特征展开论述,通过比较分析法将学科研学与校内课堂学习、户外拓展训练、外出游学、学科知识培训作逐一区分,可为其他同行设计开发学科研学课程提供些许思路和参考。

初中历史学科研学教育实践研究

历史学科作为初中的重要学习内容,是一门知识点丰富的学科,需要教师与时俱进不断创新教学方式,帮助学生提高学习效率。历史学科的研学教育通过主题性的教育方式,激起学生在历史学习中的兴趣,同时通过教师及时地引导和组织,培养学习兴趣。初中阶段历史教学开展研学教育能够培养学生自主学习能力,让学生通过探索的方式积累更多学科知识。

基于“五育融合”理念的小学语文研学创新性研究

“五育融合”理念为小学学科教学带来了别样的生机与活力,而学科研学活动能较快地提升小学生的学科核心素养。笔者认为,小学学科研学可以采取多元化的方式,为学生们创造自由、新颖的学习空间,促进学生学科核心素养的提升。

The State of Geological Sciences in the USSR by the Mid-Twentieth Century

The November 1948 open session of the Institute of Geological Sciences AS USSR was previously unknown,in contrast to the August 1948 session of VASKhNIL.The publication of the transcript of the session of geologists is based on the original verified transcript from the Geological Institute and the Archive RAS.It presented reports on the main scientific directions of geology:stratigraphy,the Quaternary geology,lithology,geotectonics,petrography and petrology,mineralogy and geochemistry,and the geology of ore and coal deposits.This thick book details all the Q&A sessions,discussions of theories,methods,and practice among the leading Soviet geoscientists.The session and its resolution describe the situation and development of geology in the USSR in the mid-twentieth century as well as the collateral impact of the Lysenko affair on the earth sciences in the USSR.

胶州湾北部软底大型底栖动物丰度和生物量的研究

1995年3～11月对胶州湾北部软底海域进行了 两月一次的大型底栖动物调查。调查期间，大型底栖动物总平均丰度和总平均生物量分别为 1891.3 inds./m2和41.9 g.w.w/m2。与该海域有关大型底栖动物丰度和生物量的历史 资料相比较，本研究所得到的大型底栖动物丰度值显著增加，生物量值则有较明显的下降， 初步分析了发生这些变化主要原因。丰度和生物量比较曲线表明，所研究海域底栖生物群落 处于中等干扰(即污染的影响 )状态。

Recent sedimentary records in the East China Sea inner shelf and their response to environmental change and human activities

The East China Sea continental shelf is a unique area for the study of land-sea interactions and paleoenvironmental change because it receives a large amount of terrestrial material inputs. In recent decades, human activities and global climate change have greatly aff ected river discharges into the sea. However, changes in the deposition process caused by these factors in the East China Sea continental shelf are unclear. We collected eight short sediment cores from the East China Sea inner shelf(ECSIS) using a box core sampler in 2012 and 2015. The grainsize, 2 10 Pb, and 1 37 Cs of these cores were analyzed in order to reconstruct the deposition history since the 1950 s, and to reveal human activity and climate change influences on sediment deposition in the ECSIS. Results indicated that sediment grain size became finer after 1969, turned coarser after 1987, and then further coarser since 2003, corresponding well to the three steps of sediment load drop in the Changjiang(Yangtze) River, which are mainly caused by human activities(particularly the closure of the Three Gorges Dam). Simultaneously, the East Asian Monsoon influenced the deposition process in the ECSIS by changing the intensity of coastal currents. Mean grain size variations in the fine-grained population(divided by grain size vs. standard deviation method) coincided with that of the East Asian Winter Monsoon strength and reflected its weakness in 1987. Abrupt changes in sediment grain size over a short time scale in these sediment cores were generally caused by floods and typhoons. Spectral analyses of the sediment cores showed periodicities of 10–11 and 20–22 years, corresponding to the periodicity of solar activity(Schwabe cycle and Hale cycle). Mean grain size time series also displayed a 3–8 year periodicity corresponding to El Ni?o Southern Oscillation periodic change.

Physiological diversity of orchids

The Orchidaceae is a diverse and wide spread family of flowering plants that are of great value in ornamental, medical, conservation, and evolutionary research. The broad diversity in morphology,growth form, life history, and habitat mean that the members of Orchidaceae exhibit various physiological properties. Epiphytic orchids are often characterized by succulent leaves with thick cell walls,cuticles, and sunken stomata, whereas terrestrial orchids possess rhizomes, corms, or tubers. Most orchids have a long juvenile period, slow growth rate, and low photosynthetic capacity. This reduced photosynthetic potential can be largely explained by CO_2 diffusional conductance and leaf internal structure. The amount of light required for plant survival depends upon nutritional mode, growth form,and habitat. Most orchids can adapt to their light environments through morphological and physiological adjustments but are sensitive to sudden changes in irradiance. Orchids that originate from warm regions are susceptible to chilling temperatures, whereas alpine members are vulnerable to high temperatures.For epiphytic orchids, rapid water uptake by the velamen radicum, water storage in their pseudobulbs and leaves, slow water loss, and Crassulacean Acid Metabolism contribute to plant-water balance and tolerance to drought stress. The presence of the velamen radicum and mycorrhizal fungi may compensate for the lack of root hairs, helping with quick absorbance of nutrients from the atmosphere.Under cultivation conditions, the form and concentration of nitrogen affect orchid growth and flowering.However, the limitations of nitrogen and phosphorous on epiphytic orchids in the wild, which require these plants to depend on mycorrhizal fungi for nutrients throughout the entire life cycle, are not clearly understood. Because they lack endosperm, seed germination depends upon obtaining nutrients via mycorrhizal fungi. Adult plants of some autotrophic orchids also gain carbon, nitrogen, phosphorus, and other elements from their mycorrhizal partners. Future studies should examine the mechanisms that determine slow growth and flower induction, the physiological causes of variations in flowering behavior and floral lifespan, the effects of nutrients and atmospheric-nitrogen deposition, and practical applications of mycorrhizal fungi in orchid cultivation.

Water masses in the far western equatorial Pacific during the winters of 2010 and 2012

Conductivity-temperature-depth（CTD）data obtained during the 2010 La Nina winter and the 2012 normal winter,combined with concurrent Argo profiling float data,provide a quasi-synoptic description of the water mass distributions and their variations in the far western equatorial Pacific Ocean.The water mass connection between the western Pacific and the east Indonesian seas is emphasized.Analysis indicates that the North Pacific Tropical Water（NPTW,S〉34.9）carried by the Mindanao Current southward and the South Pacific Tropical Water（SPTW,S〉35.1）from the southern hemisphere meet in the area.Observations suggest that the southward transport of the NPTW is stronger in 2010 than in 2012 due to enhanced advection of the Mindanao Current.The distribution of SPTW,which crosses the equator in the northwest direction and retroflects back to the interior Pacific Ocean,is found to retreat from 4°–5°N in2012 to 2°–3°N in 2010 La Ni？a peak in the 130°E section.A relatively fresh tropical subsurface water is identified in between the NPTW and the SPTW,moving eastward with the North Equatorial Countercurrent into the equatorial Pacific Ocean.However,the salinity maximum of this subsurface fresh water is found to decrease eastward,suggesting that the salinity maximum is generated either by strong diapycnal mixing or by isopycnal mixing of temporally entrained Indonesian sea water into the area.

Diversity of desert rangelands of Tunisia

Plants are important components of any rangeland.However,the importance of desert rangeland plant diversity has often been underestimated.It has been argued that desert rangelands of Tunisia in good ecological condition provide more services than those in poor ecological condition.This is because rangelands in good condition support a more diverse mixture of vegetation with many benefits,such as forage for livestock and medicinal plants.Nearly one-quarter of Tunisia,covering about 5.5 million hectares,are rangelands,of which 87% are located in the arid and desert areas(45% and 42%,respectively).Here,we provide a brief review of the floristic richness of desert rangelands of Tunisia.Approximately 135 species are specific to desert rangelands.The predominant families are Asteraceae,Poaceae,Brassicaceae,Chenopodiaceae,and Fabaceae.These represent approximately 50% of Tunisian desert flora.

A preliminary study of cryosphere service function and value evaluation

Cryosphere science research and development(R&D) has been strongly committed to public service, integrating natural sciences with socioeconomic impacts. Owing to the current shift from purely natural cryosphere scientific research to linking cryosphere science with socioeconomic and cultural science, cross-disciplinary research in this field is emerging, which advocates future cryosphere science research in this field. Utilizing the cryosphere service function(CSF), this study establishes CSF and its value evaluation system. Cryosphere service valuation can benefit the decisionmakers' and public's awareness of environmental protection. Implementing sustainable CSF utilization strategies and macroeconomic policymaking for global environmental protection will have profound and practical significance as well as avoid environmental degradation while pursuing short-term economic profits and achieving rapid economic development.

Seasonal comparison of bacterial communities in rhizosphere of alpine cushion plants in the Himalayan Hengduan Mountains

Positive associations between alpine cushion plants and other species have been extensively studied.However,almost all studies have focused on the associations between macrofauna.Studies that have investigated positive associations between alpine cushion plants and rhizospheric microbes have been limited to the vegetation growing season.Here,we asked whether the positive effects that alpine cushion plants confer on rhizospheric microbe communities vary with seasons.We assessed seasonal variations in the bacterial diversity and composition in rhizosphere of two alpine cushion plants and surrounding bare ground by employing a high throughput sequencing method targeting the V3 region of bacterial 16 S rRNA genes.Soil properties of the rhizosphere and the bare ground were also examined.We found that cushion rhizospheres harbored significantly more C,N,S,ammonia nitrogen,and soil moisture than the bare ground.Soil properties in cushion rhizospheres were not notably different,except for soil pH.Bacterial diversities within the same microhabitats did not vary significantly with seasons.We concluded that alpine cushion plants had positive effects on the rhizospheric bacterial communities,even though the strength of the effect varied in different cushion species.Cushion species and the soil sulfur content were probably the major factors driving the spatial distribution and structure of soil bacterial communities in the alpine communities dominated by cushion plants.

Study on the efficiency of equipment shared by universities

Based on the theory of data envelopment analysis, this paper sets up the super-efficiency data envelopment analysis （DEA） model. It makes use of the model to evaluate efficiency of equipment shared by universities in Tianjin. It explored database of many universities and put forward suggestions to improve the efficiency of equipment shared by universities at present.

Global progress against cancer—challenges and opportunities

The last ten years have seen remarkable progress in cancer research. However, despite significant breakthroughs in the understanding, prevention, and treatment of cancer, the disease continues to affect millions of people worldwide. Cancer＇s complexity compounded with financial, policy and regulatory roadblocks has slowed the rate of progress being made against cancer. In this paper, we review a few of the most recent breakthroughs that are fueling medical advances and bringing new hope for patients affected by this devastating disease. We also address the challenges facing us and the opportunities to accelerate future progress against cancer. The efforts of the American Association for Cancer Research （AACK） to address the cancer burden already extend beyond the borders of the United States of America. The AACR is committed to increasing its efforts to stem the tide of cancer worldwide by promoting innovative programs, strategies, and initiatives for cancer researchers and all those engaged in cancer-related biomedical sciences around the world.

Generation and characterization of expressed sequence tags(ESTs) from coralloid root cDNA library of Cycas debaoensis

A normalized full-length cDNA library was constructed from the coralloid roots of Cycas debaoensis by the DSN （duplex-specific nuclease） normalization method combined with the SMART （Switching Mechanism At 5＇ end of the RNA Transcript） technique. The titer of the original cDNA library was about 1.5 × 10^6 cfu·mL^-1 and the average insertion size was about 1 kb with a high recombination rate （97%）. The 5011 high-quality expressed sequence tags （ESTs） were obtained from 5393 randomly picked cDNA clones. Clustering and assembly of ESTs resulted in 2984 unique sequences, consisting of 618 contigs and 2366 singlets. EST sequence annotation revealed that 2333 and 1901 unigenes were functionally anno- tated in the NCBI non-redundant database and Swiss-Prot protein database, respectively. Functional analysis demonstrated that 1495 （50.1%） unigenes were associated with 4082 Gene Ontology （GO） terms. A total of 847 unigenes were grouped into 22 Cluster of Orthologous Groups （COG） functional categories. Based on the EST dataset, 22 ESTs that encoded putative receptor-like protein kinase （RLK） genes were screened. Furthermore, a total of 94 simple sequence repeats （SSRs） were discovered, of which 20 loci were successfully amplified in C debaoensis. This study is the first EST analysis for the coralloid roots of C debaoensis and provides a valuable genomic resource for novel gene discovery, gene expression and comparative genomics, conservation and management studies as well as applications in C debaoensis and related cycad species.

Synthesis of Humin-based Carbon Quantum Dots and Luminescent Properties

The unique properties of carbon quantum dots （CQDs） make them promising materials in many ？elds. Herein, we present a facile method for the preparation of photo-luminescent CQDs using humins as the carbon precursor for the purpose of providing a high value-added solution for this “biomass conversion process waste”. The structure of the CQDs was analyzed, and the effects of reaction temperature and time on the CQDs’ ？uorescence were investigated. The results showed that humins were effectively carbonized during the reaction. The ？uorescence intensity of humin-based CQDs initially increased with reaction temperature and time, and subsequently decreased beyond 200℃ and 4 h. Polyaromatic structures and hydrophilic groups such as O-H, C-O, -COOH and C==O groups exist in the CQDs. The humin-based CQDs have the dimension of 3~7 nm with an average size of about 5.5 nm. The highest emission intensity of blue/cyan ？uorescence light at 440 nm is achieved on the excitation with UV light at the wavelength of 330 nm.

Epitome of Research on the History of Science and Technology in China:A Review of the Book Series History of Science and Technology in Pre-Modern China in Comparison with Needham’s Science and Civilisation in China

The early twenty-first century witnessed the publication of the book series Zhongguo kexue jishu shi中国科学技术史(History of science and technology in pre-modern China),which was initiated and organized by the Institute for the History of Natural Sciences,Chinese Academy of Sciences,and compiled by a multitude of Chinese scholars.In comparison with Science and Civilisation in China by Dr.Joseph Needham,Zhongguo kexue jishu shi is superior in the layout characteristics,literature collection,research and explication,field investigation,and simulation experiments.

Film mulching treatment inf luences dry matter and yield of oil flax in semi-arid area of China

A feld study was set up to compare dry matter accumulation and grain yield of 3 different types of flm mulching, namely FFC （full flm muched on tiny ridges covered with soil）, PFC （full flm muched covered with soil）, and PF （full flm muched with no cover）. The experiment was laid out in a complete random design with 3 replications at north-west （34°40′N, 105°06′E） of China. This study determined that （1） flm mulching treatment increased leaf area and dry matter accumulation of oil fax in semi-arid areas; （2） accu-mulation of dry matter under PFC treatment was markedly higher than other treatments except anthesis stage; （3） average grain yield of oil fax under flm mulching treatment was 52.67%-60.33% higher than fat plot without mulched or ridge （CK） treatment; （4） grain yield of oil fax was substantially correlated with plant height, grain number and 1,000 kernels weight. This study demonstrated that flm mulching has signifcant effects on crop grain yield improvement in the northwest of China.

Upper-ocean temperature trends in the Eastern China Seas during 1976–1996

Temperature in the Eastern China Seas(ECS), including the Bohai, Yellow, and East China seas, is crucially important with regard to weather forecasting and fishery activities of adjacent countries. Although sea surface temperature(SST) in the ECS has demonstrated a dramatically accelerated trend of warming after a regime shift(1976–1996), trends beneath the surface remain poorly understood because of the sparsity of observations. This study used in situ hydrographic data from 1976 to 1996 to examine upperocean temperature trends in the ECS. It was found that the multilevel trends show consistency with that of the surface water; i.e., warming is faster in winter than summer. However, the magnitudes of the trends weaken with increasing depth. Furthermore, the seasonal dif ference in the upper ocean is mainly associated with the warm currents in the ECS, which implies an essential contribution from horizontal advection. These phenomena could also be detected from data acquired from the routinely observed PN and 34°N sections. The spatiotemporal patterns of temperature trends in the upper ECS extend our understanding beyond the SST, especially highlighting the role of ocean dynamics in forming temperature patterns beneath the surface in comparison with atmospheric ef fects.

Point Set Generalization Based on the Kohonen Net

Point set generalization is one of the essential problems in map generalization. On the demands analysis of point set generalization, this paper proposes a method to generalize point sets based on the Kohonen Net model; the standard SOM algorithm has been improved so as to preserve the spatial distribution properties of the original point set. Examples illustrate that this method suits the generalization of point sets.

The Geostatistical Framework for Spatial Prediction

Geostatistics provides a coherent framework for spatial prediction and uncertainty assessment, whereby spatial dependence, as quantified by variograms, is utilized for best linear unbiased estimation of a regionalized variable at unsampied locations. Geostatistics for prediction of continuous regionalized variables is reviewed, with key methods underlying the derivation of major variants of uni-vafiate Kriging described in an easy-to-follow manner. This paper will contribute to demysti- fication and, hence, popularization of geostatistics in geoinformatics communities.