黑龙江省伊春市桃山遗址2013年发掘报告

桃山遗址发现于2011年,2013年6-7月对遗址展开试掘,发掘面积24m2;共获得石制品982件,陶片46件,装饰品2件,未见动物骨骼。石制品类型包括石核、石片、刮削器、锯齿刃器、凹缺器、钻具、石镞、细石核、细石叶、石叶等,类型较为丰富。石制品原料以凝灰岩、玛瑙、白云岩、玄武岩和燧石为主,原料较为多样。石制品的剥片方法以锤击法为主,压制法也有使用;工具的修理方面主要采用锤击法,同时具有压制法修理的石镞和刮削器等工具。该遗址所处年代位于晚更新世末期向全新世早期转变的时期,环境变化剧烈;遗址石制品的文化内涵丰富,性质较为独特,总体呈现出从旧石器晚期向新石器时代过渡的文化面貌,层序清楚,对研究我国东北地区新旧石器文化过渡的演变机制具有非常重要的价值,并为探讨这一阶段东北亚与北美地区的人群迁徙与文化传播等学术问题提供了新的重要证据。     

黑龙江省桃山遗址2014年度发掘报告

桃山遗址发现于2011年,2013年进行试掘,并于次年展开系统的考古发掘工作。遗址2014年度发掘总面积36m~2,揭露出3个史前文化层,出土了丰富的遗物,包括石制品1943件,陶片12件,装饰品备料2件,植物果壳1件。石制品类型包括石核、石片、细石叶、鸡冠状石叶、削片、刮削器、锯齿刃器、端刮器、凹缺器、斧形器、锛形器和石镞等。此次发掘出土遗物从数量和类型两个方面均突破了2013年试掘工作对遗址认识的局限,更全面地展现出桃山遗址的文化面貌。遗址各阶段石制品原料及技术类型虽存在一定相似性,但也表现出较为明显的差异。光释光和AMS~(14)C年代测定表明古人类在该遗址活动的时间从旧石器晚期后段一直延续到新石器时代。     

江苏泗洪顺山集遗址植硅体分析及其环境意义

江苏泗洪顺山集遗址是淮河中下游地区迄今为止发现年代最早的新石器时代遗址之一。本文对遗址三个不同文化时期连续剖面土壤堆积物中的植硅体进行分析,结果显示该遗址先民早在距今8 500年左右已经开始种植水稻,并一直延续到遗址三期(7 500 BP)。植硅体组合分析结果表明,顺山集遗址所处时期的气候总体上较温暖湿润,但存在气候波动,从一期至三期大体上经历了温暖—偏凉—回暖的过程,可能对应了全新世高温期到来之前的气候转暖。从顺山集遗址水稻遗存的连续发现以及水稻驯化水平不断提高来看,气候变冷并未抑制当地稻作农业的发展,相反在一定程度上可能促进了其发展与扩散。本文研究结果对研究全新世早中期中国中东部气候变化背景下人类适应策略提供了重要的科学依据。     

华南地区史前人类骨骼的生物力学特征

本文的主要目的是了解华南地区史前时期人类在行为活动上的历时性变化,希望在此基础上认识该地区史前人类文化行为模式和生业方式变迁问题。应用骨骼生物力学方法,对顶蛳山遗址、鲤鱼墩遗址、冲塘遗址、江边遗址及何村遗址古人类肢骨的相关骨骼生物力学特征进行了比较,并在更广泛的时空范围内和生业方式下进行了更多人群的对比。研究结果表明,华南地区史前时期在距今8000-4000年的时期内,不同考古学文化人群在活动方式上较为相似。虽然多数华南史前时期人群之间在骨骼的抗压和抗拉伸力以及抗扭转力方面存在显著性差异,但他们都表现出较高的活动性,均未显示出低水平行为活动的现象。这些人群在诸多骨骼生物力学特征上与已知的狩猎—采集型人群的最为相似,与农业定居型人群的差异显著。本文认为上述华南史前时期人群在行为活动上更接近狩猎-采集型。     

南京郭家山遗址植硅体分析与湖熟文化环境背景

郭家山遗址是目前发现的距江苏南京城区最近的,较大型的湖熟文化遗址.遗址商代至西周春秋文化层的植硅体分析,揭示出南京地区在商代(约3 500-3 000 aBP)气候偏温、偏湿;西周(或西周早期)(约3 000-2 800 aBP)气候温和湿润;西周战国时期(约2 800-2 500 aBP)气候偏温、偏湿.与相邻地区同...     

射击类带尖石制品使用微痕动态形成过程的实验研究

石镞主要是旧石器时代晚期出现的一种投射类复合武器的尖端,其使用方式一直为学术界所关注。本文以山西吉县柿子滩遗址环境背景和石器原料为参照,通过微痕实验,探讨射击类带尖石制品重复使用过程中微痕的动态形成过程。作者对21件实验标本分阶段累计射击337次,微痕观察121次。分析结果显示,射击类带尖石制品的重复使用情况可以通过微痕进行佐证。形态变化过程表明,尖端变化较为显著,指示应以动态思维考量出土石镞形态及其暗示的人类行为;测量数据显示,尖端及侧刃较为锋利、长度适中的标本,射击效果更好,存在多次使用的可能;微痕分析指示,若尖端产生层叠大中型折断式、阶梯式疤痕,装柄部位产生连续小型折断式或羽翼式疤痕,部分出现磨圆与光泽时可以考虑重复使用的可能。本项研究为揭示石镞背后所蕴含的狩猎策略、生计方式等人类行为信息提供了数据参考。     

安徽蚌埠禹会村遗址植硅体分析及其指示的龙山文化时期农业活动

禹会村遗址是淮河中游地区的一处大型龙山文化时期城址,了解其农业活动有助于认识本地区新石器时代末期的农业发展水平与社会组织形式等。本文对禹会村遗址2017年和2020年两个发掘区的49份样品进行了植硅体分析,在多个遗迹单位中发现不同浓度的水稻特征性植硅体,未发现粟遗存的证据。结合已有研究成果,本文认为禹会村遗址龙山文化时期的农作物以水稻(Oryza sativa)为主,粟(Setaria italica)在农业结构中所占比重较低。遗址中发现的水稻植硅体以来自茎叶的扇型植硅体为主,而且不同区域水稻植硅体分布浓度存在明显的差异,反映禹会村遗址的水稻收割方式可能为连杆收割,将水稻带入遗址内分开完成脱粒与脱壳行为。其中城垣区水稻加工活动可能存在集中完成的现象,而生活遗迹区是以家庭为单位开展。此外,水稻扇型植硅体形态参数分析结果显示,禹会村遗址龙山文化时期水稻驯化水平较低,可能存在包括粳稻在内多个水稻品种。本文揭示了禹会村遗址龙山文化时期农业结构、农作物的加工活动及农业发展水平等相关信息,为进一步研究淮河中游地区龙山文化时期农业生产及与其相关的社会组织形式等方面提供了新的科学依据。     

广西灰窑田史前遗址人类髌骨的形态变异

距今约7000～6000年的广西灰窑田遗址是顶蛳山文化的重要遗址之一,其所出人类遗骸为探讨岭南地区史前时期渔猎-采集型人群的肢体活动方式、活动强度以及两性劳动分工等问题提供了重要的研究样本。髌骨作为膝关节的重要组成,其形态变异特征在一定程度上可以反应个体膝关节的活动程度与特点。本文采用三维几何形态测量方法对该遗址出土的43例人类髌骨进行分析,从侧别对称性、性别二态性以及年龄差异性等三个方面考察了髌骨的大小和形态差异。研究结果表明,该遗址古人类髌骨发育存在明显的左侧优势,髌尖呈右偏趋势。男性髌骨尺寸较大,但两性髌骨形态未见显著差异。该遗址个体髌骨形态随年龄增长呈现出与股四头肌力量增强、屈伸运动强度与频率增加相关的变化特征。     

周口店北京猿人遗址的年代综述兼评该遗址的铝铍埋藏年龄

本文综合评述了对周口店第一地点的测年结果。探讨了1)基于骨化石铀系、裂变径迹、古地磁和牙化石ESR测年的老年代框架与2)基于钙板铀系和铝铍埋藏测年的新年代框架之间的差异。着重分析了铝铍埋藏年龄测量方法因假设前提不完全满足而可能引起测年结果偏老的系统误差。文中还对周口店遗址进一步的年代学研究提出了建议。     

重庆忠县甘蔗丘遗址商周时期以来环境考古研究北大核心CSCD

通过对重庆忠县甘蔗丘遗址自商周时期以来的215cm厚的文化堆积层进行孢粉、炭屑和磁化率指标的综合研究。结果表明,商周时期出土器物丰富,磁化率值和炭屑浓度整体较高,但孢粉浓度很低,表明该地点处于一级阶地上,先人在此生活不仅用水方便,且因当时气候偏干凉,较少受到极端洪水灾害威胁,较高的炭屑表明了古人用火频繁。到唐宋时期中期,出土器物明显减少,孢粉浓度增大,且属种增多,尤其是喜湿植物孢粉浓度明显增大,可能表明该时期环境较为潮湿,居住地有可能受到洪水破坏,农业活动在遗址处开始发展,其炭屑浓度和磁化率值减小的特征也说明人类居住地迁出和土地性质已开始以初级农业活动为主。唐宋后期气候更为暖湿,区域降雨量增大,由于遗址区位于长江干流一级阶地上,易受洪水灾害的威胁,先民在该区的活动进一步减少。明清时期早期,孢粉浓度虽然变化不大,但水稻型禾本科花粉浓度大幅度增加,次生性的松属也相应较高,显示出人类农业活动增强,遗址地可能逐渐演变为农田;到了明清后期,炭屑浓度和磁化率值又逐渐增大并出现峰值,反映遗址区开始受到近代农业活动的强烈影响。     

The visualization of actin filament polarity in thin sections. Evidence for the uniform polarity of membrane-associated filaments

We have developed an improved method for visualizing actin filament polarity in thin sections. Myosin subfragment-1 (S-1)-decorated actin filaments display a dramatically enhanced arrowhead configuration when fixed in a medium which contains 0.2 % tannic acid. With the exception of brush borders from intestinal epithelial cells, the arrowhead periodicity of decorated filaments in a variety of nonmuscle cells is similar to that in isolated myofibrils. The periodicity of decorated filaments in brush borders is significantly smaller. Actin filaments which attach to membranes display a clear, uniform polarity, with the S-1 arrowheads pointing away from the plasma membrane, while those which comprise the stress fibers of myoblasts and CHO cells have antiparallel polarities. These observations are consistent with a sliding filament mechanism of cell motility.     

Actin-like filaments in the myoid cell of the testis

Microfilaments in the myoid cells of the peritubular tissue in the mouse, swine and human testis bind heavy meromyosin (HMM) and form arrowhead complexes. The periodicity of the arrowhead complexes is about 35 nm. Individual filaments show arrowheads that point in the same direction. Opposing polarity of the HMM-bound filaments is also observed. The microfilaments do not bind HMM in the presence of 10 mM ATP. After treatment with the contraction medium of Hoffmann-Berling, the filaments appear to be undulated. These observations indicate that the microfilaments in the myoid cell are actin-like in nature. A small number of thicker filaments (about 10 nm in diameter) which do not bind HMM is also observed in the cell. Microfibrils which have been reported around the human myoid cell are also found in the swine.     

Identification of actin in situ at the ectoplasm-endoplasm interface of Nitella. Microfilament-chloroplast association

Using a glycerination procedure designed to avoid excessive plasmolysis or disruption of the ectoplasm, microfilaments in bundles at the ectoplasm-endoplasm interface of Nitella internode cell segments were found to bind rabbit heavy meromyosin (HMM) in situ. All HMM arrowheads in a bundle seem to have the same polarity and many lie in register as judged from the electron micrographs; the arrowhead periodicity is approximately 380 . The decorated microfilaments are thus similar to those seen in negatively stained cytoplasmic suspensions of internode cells. In glycerinated material, as well as in suspensions, the microfilaments are closely associated with chloroplasts. The microfilaments lie adjacent to or are attached to the chloroplast envelope. The results provide further evidence that the microfilaments thought to play a role in cytoplasmic streaming in vivo in Nitella consist of actin and suggest that they may be anchored to the chloroplasts.     

Thin filaments of rabbit skeletal muscle are in helical register

Thin sections of rapidly frozen and freeze-substituted rabbit glycerinated muscle fibres loaded with myosin subfragment-1 were used to examine a three-dimensional arrangement of thin filaments in vertebrate skeletal muscle. Clearer images of the "arrowhead" structure were obtained when specimens were freeze-substituted first in a tannic acid solution and then in an OsO4 solution. The images obtained showed that the arrowheads were aligned laterally. This indicates that all the thin filaments have the same rotational orientation in a half sarcomere of rabbit skeletal muscle in the rigor state.     

Actin filaments in sensory hairs of inner ear receptor cells

Receptor cells in the ear are excited through the bending of sensory hairs which project in a bundle from their surface. The individual stereocilia of a bundle contain filaments about 5 nm in diameter. The identity of these filaments has been investigated in the crista ampullaris of the frog and guinea pig by a technique of decoration with subfragment-1 of myosin (S-1). After demembranation with Triton X-100 and incubation with S-1, "arrowhead" formation was observed along the filaments of the stereocilia and their rootlets and also along filaments in the cuticular plate inside the receptor cell. The distance between attached S-1 was 35 nm and arrowheads pointed in towards the cell soma. It is concluded that the filaments of stereocilia are composed of actin.     

Ultracytochemistry of the cell surface and microfilaments in dimethylhydrazine-induced colonic tumor cells

Studies were made of the ultracytochemical changes in the cell membrane and microfilaments of colonic epithelial cells during tumorigenesis induced by 1,2-dimethylhydrazine (DMH) in mice fed a high fat diet. The tumor cells showed reduced membrane ATPase activity and loss of contact with neighboring cells. Microfilaments in tumor cells showed an irregular intensity of fluorescent staining. Their actin filaments bound with heavy meromyosin (HMM) had an arrowhead pattern as in normal cells, but these complexes were shortened and detached from the cell membrane. The arrowheads were directed toward the interior in the terminal web of tumor cells. Microfilaments with long rootlets extended to the apical surface of some tumor cells. These results indicate that during development of colonic tumors, the structures of the cell membrane and microfilaments of the cells changes.     

ELECTRON MICROSCOPIC INVESTIGATIONS OF ACTOMYOSIN AS A FUNCTION OF IONIC STRENGTH

Natural actomyosin at µ = 0.6 appears in various forms, including the regular arrowhead structures originally reported by Huxley (1), when it has been stained negatively with 1% uranyl acetate. In addition to the arrowheads, thin whiskers, 700–1200 A in length and 20 A in width, attached to the arm of the arrowheads have been demonstrated. The dimensions of the whiskers and arms of the arrowheads are practically the same as those of the light meromyosin (LMM) and the heavy meromyosin (HMM) moieties of the single myosin molecule, respectively. Changes in the electron microscopically distinguishable elements during aggregation of natural actomyosin on reduction of the ionic strength have been observed. At µ = 0.4, partial aggregation of the LMM whiskers begins to result in some parallel alignment of the arrowhead-bearing filaments (acto-HMM). In the range of µ = 0.3–0.1, the LMM whiskers merge into smooth filaments which are arranged alternatingly with arrowhead-bearing filaments. Thus, lateral aggregation of composite actomyosin filaments (acto-HMM + LMM whiskers) results with the LMM moieties as links. This view is supported by the following facts: (a) acto-HMM is devoid of whiskers and does not show lateral aggregation at µ = 0.1; (b) natural actomyosin digested with trypsin at µ = 0.6, which was followed by removal of LMM aggregates at low ionic strength, is essentially the same as acto-HMM at µ = 0.1; and (c) digestion with trypsin of natural actomyosin at µ = 0.2 for varying periods of time leads to a separation of arrowhead-bearing filaments from LMM aggregates.     

Bidirectional polymerization of G-actin on the human erythrocyte membrane

The directional polymerization of actin on the erythrocyte membrane has been examined at various concentrations of G-actin by thin-section electron microscopy. For this purpose, a new experimental system using single-layered erythrocyte membranes with the cytoplasmic surfaces freely exposed was developed. The preformed actin filaments did not bind with the cytoplasmic surface of the erythrocyte membranes. When the erythrocyte membranes were incubated at low concentrations (0.3 and 0.5 microM) of G-actin, greater than 80% of polymerized actin filaments pointed toward the membranes mainly in an end-on fashion, as judged by arrowhead formation with heavy meromyosin. At higher concentrations (2 and 4 microM) of G-actin, about half of the polymerized actin filaments were directed with arrowheads pointing toward the membranes, while the rest of the filaments showed the opposite polarity pointing away from the membranes. The majority of polymerized actin filaments formed loops at the points of attachment to the membranes. In contrast, when G-actin (2 and 4 microM) in the presence of cytochalasin B was polymerized into filaments, approximately 70% showed the polarity pointing away from the membrane mainly in an end-on fashion. To check the treadmilling phenomena, the erythrocyte membranes with bidirectionally polymerized actin filaments were further incubated with G-actin at the overall critical concentration. In this case, almost all (90%) of actin filaments showed the polarity with arrowheads pointing toward the membranes. The results obtained are discussed with special reference to the mode of association of actin filaments with the plasma membrane in general.     

Myosin and actin from Escherichia coli K12 C600.

Myosin-like protein and actin-like protein from E. coli formed filaments very similar in structure to those of myosin and actin from skeletal muscle. At 0.2 M KCl, a large number of "thick filaments" of uniform size (about 0.6-0.7 micron long and about 20 nm wide) was present. These thick filaments aggregated as the KCl concentration decreased to less than 0.2 M. Filaments of actin-like protein were decorated with muscle heavy meromyosin, showing "arrowheads". The arrowhead structure disappeared in the presence of ATP. A mixture of E. coli myosin-like protein and rabbit skeletal actin exhibited a gelation phenomenon on the additon of ATP. The phenomenon was reversible and showed ATP specificity. However, the gelation phenomenon was not observed with the mixture of E. coli actin-like protein and E. coli myosin-like protein. These results provide compelling evidence that the E. coli myosin-like protein and actin-like protein we isolated are essentially identical to myosin and actin, respectively.