Effect of spatial heterogeneity on natural regeneration of Manchurian ash

The spatial patterns of seedlings originating from natural regeneration are often heterogeneous since they are strongly influenced by microsite gradient. We supposed that the patterns of Manchurian ash (Fraxinus mandshurica Rupr.) seedlings, which were originated from natural seed rain, were also spatial heterogeneous in spite of relative homogeneous of planted forest. The tree seedling establishment and growth were monitored in the Forest-experimental-station of Northeast Forestry University during growing season from early May to late September in 1999. The emergence of seedlings began in middle May; but the peak was about in late May. Seedlings were counted in 635 grid cells in late June, there were about 16–30 individuals/m2, but almost all of them died off in late September. The scale and extent of seedling heterogeneity were assessed by semivariogram and fractal dimension. The study showed that over 70% of seedling pattern was spatially autocorrelated, and that the variation caused by random factors was in less than 30%. The spatial dependent scales, both isotropy and anisotropy, were 1.95–2.92 m and 1.83–6.40 m respectively in the research stands. Our hypothesis was supported although there was difference when samples were chose at both different spatial scale and different density stands.

Antifatigue,Antioxidant and Immunoregulatory Effects of Peptides Hydrolyzed from Manchurian Walnut(Juglans mandshurica Maxim.) on Mice

The Manchurian walnut(Juglans mandshurica Maxim.) is rich in proteins, whereas this resource has not been used efficiently. The antifatigue, antioxidative and immunoregulatory effects of Manchurian walnut hydrolysate peptides(MWHPs)were evaluated in this study. MWHPs with a degree of hydrolysis of 32.23% were ultrafiltered and divided into three fractions,namely, high(> 10 k Da), medium(3–10 kDa), and low molecular weight(< 3 kDa), and then fed to mice continuously at doses of 200, 400 or 800 mg/(kg·d). The antifatigue, antioxidative, and immunoregulatory effects of the peptides were tested on the second and fourth weeks of MWHP administration. Results showed that low-molecular-weight MWHPs exerted significant antifatigue(prolonging swimming time, elevating liver glycogen contents, and reducing lactic acid contents), antioxidative(enhancing superoxide dismutase(SOD), GSH-Px, and catalase(CAT) activities and reducing malondialdehyde(MDA) content), and immunoregulatory(raising the immune-organ index and promoting T-lymphocyte proliferation and s Ig A secretion in the intestinal tract) effects. This research indicates that MWHPs have potential applications in health care and may be developed as a base for new functional foods.

GROWTH EFFECT OF DAHURIAN LARCH-MANCHURIAN ASH MIXED FORESTS

With the method of stem analyses by the microscope, the xylem’s accumulations atdifferent ages were quantitatively studied using the data of typical plant association for Dahurianlarch (Larix gmelini Rupr) and Manchurian ash (Fraxinus mandshurica Rupr) mixed forests. Thedeveloping process for this important mixed forest type in the study area was systematically established. The result showed that in the artificial stand of Dahurian larch mixed with naturalManchurian ash. only those which have the same origin as Dahurian larch can grow up before theclosing of stand and form the components of the main layers. After 24 years seif-thinning, when theywere 29 years old, Dahurian larch would be at the stage of no self-thinning. At last the stand woulddevelop to the broad-leaved forests dominating with the Manchurian ash.

STUDY ON THE NATURAL REGENERATION EFFECT OF MANCHURIAN ASH BY OPENING UP EFFECT BELT IN DAHURIAN LARCH PLANTATION

Opening up effect belt in dahurian larch (Larix gmelini) plantation can significantly promote the growth and development of manchurian ash (Fraxinus mandshur-ica) natural regcneration seedlings. The quantity, growth and distribution characters of manchurian ash natural regeneration seedling and the seed quantity of manchurian ash on the effect belt are significantly much more than that on remained belt. It provides a theoretical basis for using the management method of - Cutting coniferous to introduce broadleal trees in the coniferous stand, improving the stand structure, increasing the ecological stability and biological productivity.

MANCHURIAN ASH SEED BANK AND SEEDLING RECRUITMENT

To understand the natural regeneration of manchurian ash and the seed banks under various secondary stands, we have investigated the seed quantity and vitality of major trees in the ground floor of the stands. In natural secondary stands and dahurian larch plantations with seed source of manchurian ash around them, the vital seed numbers of valuable trees (mono maple, manchurian ash, amur linden, manchurian linden, manchurian walnut) are 20933/ha and 18000/ha respectively. The numbers of manchurian ash seeds arc 11000/ha and 12133/ha respectively. It has been found that litter affects the seedling recruitment of manchurian ash. When the seeds were sown on the litter and under the litter respectively, the final seedling recruitment rates were 17.9 and 28.9% respectively. The peak of seedling recruitment in the former case occurred one year later.

The Manchurian Plague and the International Plague Conference:Revisiting Wu Lien-Teh

The Manchurian plague from the winter of 1910 to the spring of 1911 was the worst epidemic in modern China, and the ensuing International Plague Conference marked the first international medical conference hosted by China. There was a close connection between these two historical events, and Wu Lien-Teh 伍连德, later extolled as the "pioneer of modern medicine in China," played a significant role in each. Despite a multitude of treatises discussing the Manchurian plague and the International Plague Conference, as well as biographical articles on the undertakings of Wu, there remains a gap in the research of Wu’s relation with these two historical events, which is worth further exploration. In addition to the key role and significance of Wu in the entire epidemic fight, the first section of this article analyzes whether the common portrayal of Wu as an obscure, local doctor transformed overnight into a Manchurian plague fighter is accurate. Through an analysis of the conference minutes, the second section focuses on how Wu used "conference diplomacy" to mitigate the neighboring powers’ attempts to achieve their political goals by leveraging this international conference.

欧李学名和汉语名称的进一步研究

【目的】为了加深大众对于欧李的认知,促进欧李科研和生产的发展。【方法】在杜俊杰教授等研究成果的基础上,进行了文献考证和走访调查。【结果】‘欧李’的学名建议采用Cerasus humilis (Bge.)Sok.,欧李学名的发表时间建议采用1835年,‘欧李’标本是欧洲人在北京西部山区考察时初次采集。现代植物学专著中最早记载‘欧李’汉语名称的是日本人矢部吉祯(Yabe Yoshisada),时间是1912年,欧李是汉语名称,乌喇柰是欧李的满语名称,‘乌喇柰’、‘欧李’在明代(1368—1644)《群芳谱》中没有记载,‘欧李’这个名称在清代(1644—1912)东北的方志以及诗文中的记载是连续的,‘欧李’名称源于明代初年的《救荒本草》,‘欧李’与‘郁李’在该书中被认为是同一种植物,‘欧李’名称的起源地是在山西省南部地区。【结论】在欧李的学名和汉语名称起源、演化等方面取得了新的进展。

Role of hydrogen peroxide in stress-induced programmed cell death during somatic embryogenesis in Fraxinus mandshurica

We examined how reactive oxygen species, in the form of hydrogen peroxide (H2O2), affect osmotic stress–induced programmed cell death during somatic embryogenesis from cotyledon explants of Manchurian ash (Fraxinus mandshurica Rupr.). We found that substantial osmotic stress was essential for Manchurian ash somatic cells to obtain embryogenic competence. The explant cells displayed hallmarks of programmed cell death, chromatin condensation, and DNA fragmentation to oligonucleotides during somatic embryogenesis. Increasing concentrations of plant growth regulators and sucrose in the medium increased osmotic stress thereby inducing H2O2 accumulation in the explant cells. We found that H2O2 concentration was significantly decreased in explant cells when the induction medium was modified, i.e., when reducing the concentration of sucrose, which reduces the osmotic pressure of the medium, or by withdrawing plant growth regulators at mid-culture. These treatments also decreased the proportion of explant cells undergoing programmed cell death. Accordingly, a decreased rate of somatic embryo induction was observed. These results show that PCD occurred during tissue browning and death of some explant cells during somatic embryogenesis in F. mandshurica. The ROS contributed to PCD in abiotic stress stimulated F. mandshurica cells.

Shoot multiplication of Syringa reticulata var.mandshurica from in vitro cultured seedlings

We developed a shoot multiplication protocol for Syringa reticulata Blume vat. mandshurica Hara from in vitro cultured seedlings that derived from in vitro germinated seeds. The shoots could be induced on Murashige and Skoog （MS） medium with proper plant growth regulator combinations of 6-benzylaminopurine （BA） and indole-3-butyric acid （IBA）. The better medium for shoot multiplication and growth was MS ＋ 5 mg L-1 BA ＋ 0.5 mg L-1 IBA ＋ 20 g L-1 sucrose ＋ 7 g L-1 agar, and the corresponding shoot induction rate was 75 %. The plantlets grew well after rooting on I/2MS medium （macro-elements of MS medium are at half-strength） sup- plemented with 1 mg L-1 IBA, and the survival percentage was 〉80 % at 16 weeks after transplanting.

Reactive oxygen species, nitric oxide and plant cell death associated with caspase-like protease activity during somatic embryogenesis in Fraxinus mandshurica

Programmed cell death occurs in browning explants of Fraxinus mandshurica during somatic embryogenesis, but the underlying mechanism is unclear. In this study, single cotyledons of zygotic embryos of F. mandshurica were used as explants. Mitochondrial structure and function, caspase-3-like protease activity, hydrogen peroxide metabolism, and nitric oxide accumulation induced by high concentrations of sucrose and plant growth regulators were studied. The results show that plant growth regulators induced somatic embryogenesis and also promoted explant browning. High sucrose concentrations had similar effects. High concentrations of sucrose and plant growth regulators led to the accumulation of hydrogen peroxide and nitric oxide which induced changes in mitochondrial structure and function such as modifications in mitochondrial morphology, increased membrane permeability, decreased membrane potential, and the release of cytochrome c into the cytoplasm. An increase in caspase-3-like protease activity triggered programmed cell death in some browning explant cells. During somatic embryogenesis there were increased activities of superoxide dismutase, peroxidase, and catalase, which are associated with hydrogen peroxide metabolism and jointly maintain reactive oxygen species levels. Intracellular nitric oxide synthase and nitrate reductase activities were not significantly correlated with nitric oxide content. Instead, intracellular nitric oxide may be derived from non-enzymatic reactions. Our results indicate that hydrogen peroxide and nitric oxide may function as signals, playing key roles in somatic embryogenesis and programmed cell death of explant cells of F. mandshurica. The interaction between nitric oxide and reactive oxygen species determines the occurrence of programmed cell death in explant cells;somatic embryogenesis and programmed cell death are positively regulated by hydrogen peroxide. However, the regulation of nitric oxide is complex.

THE SEASONAL DYNAMICS OF NUTRIENT CONTENTS IN MANCHURIA ASH-DAHURIAN LARCH MIXED STAND

The yield increasing mechanism of the manchurian ash (Fraxinus mandchurica) and dahurian larch(Larix gmelini) mixed stand was studied on nutrition status of soil and leaves. The results showed that nutrient contents of leaves and contents of the available nutrients of soil in the mixed and pure stands varied with seasons of the year. The available phosphorus contentS of the soil in the larch belt were much higher than those in the manchurian ash belt during growhg season, with the highest value of 3.5 mg/100g, 2~3 times of the latter. The nitrogen contents of leaves of the manchurian ash trees nearest from dahurian larch belt wer 12.7%~80.8% higher than those of its pure stand, and phosphorus 13.4%~140. 8%. The different uptake thythm of the nutrients modified the interspecific competition. The general conclusion is that the high contents of available phosphorus of the soil in dahurian larch belt improved the growing condition of nearby manhurian ash trees.

Chemical characterization of smoke from the production process of wood-plastic composites

The chemical composition of unpleasant smell, emitted from the production process of wood-plastic composites using Manchurian ash sawdust （Fraxinus mandschurica Rupr.） and polypropylene powder as the raw material, was investigated. Wood sawdust and polypropylene powder were subjected to heat treatment to 290℃ during 8 min （the conditions were similar to those employed on an industrial scale）. The emitted compounds were collected and analyzed by gas chromatography-mass spectrometry （GC-MS）. The analytical results showed that the unpleasant smell was emitted from the pyrogenation of wood sawdust rather than from the polypropylene powder. Nine types of compounds （hydrocarbons, ethers, phenols, aldehydes, ketones, alcohols, acids and their derivatives, furan and its derivatives, and nitrogen-containing compounds） were collected in the gas phase during heating. Among those 126 components detected by GC-MS, 112 compounds were identified.

The Treaty of San Francisco From the Perspective of International Peace Movements in Early Twentieth-Century America

The leaders of the Meiji Restoration believed in their master, Yoshida Shoin （吉田松陰）, who claimed that in order for the islands of Japan not to be a colony of the powerful Western states, Japan had to conquer nearby countries. This led to Japan’s invasion of the Ryukyu Islands, Taiwan, Korea, and Manchuria, which ultimately led to the Manchurian Incident of 1931, the Sino-Japanese War, and the Pacific War. Surprisingly, the subject and the timing of each and every one of these acts of war were in the same order of Yoshida Shoin’s proposal on preoccupancy. The Sino-Japanese war of 1894 was romanticized as clearing the barbaric culture by civilization, and the Russo-Japanese war of 1904 was romanticized as the realization of Eastern Peace. However, Japanese policies of aggressions were first deemed illegal by international law during the 1931 Manchurian Incident by the investigations of the League of Nations. The Japanese Empire received the recommendation by the League of Nations to restore to original state, but declined and exited from the League of Nations. Following their exit, they started the Sino-Japanese War and the Pacific War and eventually lost in 1945. The goal of the San Francisco Peace Treaty of 1951 was to punish Japan’s aggressions. However, as the Cold War between the East and the West started to arise in 1948, the punishment was eased, and their punishment for the aggressions on the Ryukyu Islands, Taiwan, and Korea was nearly unasked for. This paper examines the issues of the San Francisco Peace Treaty in the views of the international law of the League of Nations, established by Manley O. Hudson of Harvard University and others in U.S. academia and judiciary.

A Genealogical Study of Facemasks in China:From Hygienic Modernity to Care

Despite the omnipresence of facemasks in the ongoing COVID-19 pandemic,recent studies on their sociopolitical aspects remain insufficient.This article conducts a genealogical study that investigates the emergence of two differing masking strategies in two epidemic events in Chinese history.First,during the Manchurian plague 1910/11,it shows how the germ theory and historical anecdotes made anti-plague masks thinkable and practicable as a solution not only for airborne contagion but also for the biopolitical problem of‘unhygienic’population.In the second part,the analytical focus is shifted to the emergence of collective mask-wearing practices during SARS 2002/03 from the vantage point of subjectification.Facemasks then became a symbol of care in the neoliberal regime of responsibilization.This article concludes by arguing for a rethinking of facemasks as actants who actively participate in the constitution of the world we share.

The Mantetsu Employee Association and Mukden Incident

The Mantetsu Employee Association(MEA)was a complex organization with various platforms,whose importance had not been acknowledged at the beginning of its establishment.After the outbreak of the Mukden Incident,MEA published two“Proclamations,”blatantly boasting of the“triumph”of Japanese invasion.Its members directly took part in military actions of the Kwantung Army,assisted the Kwantung Army with invasion,and performed actively in plotting the illegal establishment of Manchukuo.After Japan’s occupation of Northeast China,MEA regularly organized grand memorial activities to the Incident,so as to strengthen the consolidation of“Japanese in Manchuria.”MEA was an important force in Japan’s colonization of Northeast China,which endeavored to support Japan’s colonial rule in the region.