不同方法制备的Pt对电极染料敏化太阳能电池的光电性能研究

采用磁控溅射（sputtering）、高温热分解（high-temp）H2Pt Cl6·6H2O溶液和低温化学还原（low-temp）H2Pt Cl6·6H2O溶液等方法在FTO导电基片上制备了三类不同的Pt对电极,通过改变磁控溅射时间或旋涂退火循环次数,对FTO上不同对电极的载Pt量进行了调节.分析了三种不同方法制备的对电极的晶相结构、表面形貌以及透光率等特性.基于纳米管阵列和不同条件制备的对电极组装了系列染料敏化太阳能电池.测量了正照射和背照射条件下的电池光电性能,并分析了制备方法对对电极微结构和形貌的影响,以及对组装电池光电性能的影响,并对其各自的适用性和优缺点进行了比较分析.     

Eine Methode zur Trockenfixation grossflächiger Kryostatschnitte

Summary By exposure to formaldehyde vapor after freeze-drying large cryostat sections are brought into a stable form. These sections can be used for documentation and may be compared easily with autoradiograms made of the same slices. Furthermore, a method is shown of evaluating these sections with a thin-layer scanner and a 2-flow counter, or by measuring quantitatively the radioactivity of single, excised organs or parts of tissues after automatic combustion by liquid scintillation counting.     

Novel approaches to the treatment of small-cell lung cancer

Small-cell lung cancer (SCLC) is characterized by its initial responsiveness to chemotherapy and the appearance of early metastases. Although combination chemotherapy, in some instances together with radiation, has improved the prognosis of this disease, in most patients SCLC ultimately recurs in a drug-resistant form. Several new strategies for the eradication of SCLC are being explored at the preclinical level. The identification of selective target molecules on the surface of SCLC cells, together with the progress made in antibody engineering, have provided new generations of antibodies and immunoconjugates as well as growth factor antagonists and inhibitors. In addition, recent advances in understanding the biology of SCLC have stimulated new investigations searching to counter the molecular basis underlying the increased proliferation and the apoptosis deficiency of SCLC cells. This can be achieved using antisense oligodeoxynucleotides that repress the expression of growth factor receptors and anti-apoptosis genes, or by gene replacement to compensate for the loss or inactivation of tumor suppressor genes.     

B7-H6/NKp30 interaction: a mechanism of alerting NK cells against tumors

Natural killer (NK) cells are lymphocytes of the innate immune system that sense target cells through a panel of activating and inhibitory receptors. Together with NKG2D, the natural cytotoxicity receptors (NCRs) are major activating receptors involved in tumor cell detection. Although numerous NKG2D ligands have been identified, characterization of the molecules interacting with the NCRs is still incomplete. The identification of B7-H6 as a counter structure of the NCR NKp30 shed light on the molecular basis of NK cell immunosurveillance. We review here the current knowledge on NKp30 and B7-H6, and we discuss their potential role in anti-tumor immunity.     

Analytisch-chemische Bestimmung nichtradioaktiver Stoffe mit einem Flüssig-Szintillationsspektrometer durch Radiolumineszenz und Absorptionsphotometrie im Čerenkov-Licht

Summary Three techniques are described which allow a quantitative chemical determination of non-radioactive substances by the means of a liquid scintillation counter. The first method is based on the chemical quenching of a radioluminescent solution through the substance that is to be determined. The second method may be described as absorption photometry in erenkov-light and the third one as absorption photometry in radiofluorescence light.     

铜合金三酸抛光微观效果研究

通过扫描电子显微镜微观观察的方法对三酸化学抛光液中各组分对铜合金表面抛光效果的影响进行了研究.结果表明,采用微观观察法能够更直观有效地研究各组分对铜合金表面抛光效果的影响,在此基础上,获得铜合金表面最佳抛光液:磷酸200~300ml/L、硫酸200~400ml/L(磷酸+硫酸500~600ml/L)、硝酸200~250ml/L(紫铜)、40~150ml/L(黄铜)、盐酸5~15ml/L.经处理的铜合金表面不仅外观光亮、微观平整,而且铜合金表面制备的转化膜中性盐雾测试时间更长、防腐性能更好.根据扫描电子显微镜观察铜合金微观形貌获得最佳抛光液组成的方法,简单方便、准确有效     

Autoradiography and differential hemoglobin staining as aids to the study of fish hematology

Summary The confused state of the existing knowledge regarding the cell types in peripheral blood and hematopoiesis of fishes has been highlighted. Inadequacies of techniques presently used have been pointed out and the advantages of using Graham-Knoll's method for haemoglobin staining when counter stained with Giemsa together with autoradiography using tritiated thymidine have been demonstrated.Thanks are due to the University of Rajasthan for working facilities. J.S.D. is grateful to University Grants Commission, New Delhi for grant of Research Fellowship during the tenure of which this work was done.     

Eine vollautomatische Probenverbrennungsanlage für die Messtechnik von H-3 und C-14 im Flüssigszintillations-Spektrometer

Summary To avoid quench corrections in liquid scintillation counting, an automatic sample-combustion device has been developed. Triggered by the preset time of whatever liquid scintillation counter is available and connected to it by an extended surveyor belt, the designed machine burns each sample, dissolves the combustion products, CO₂ and H₂O, in the scintillator solution and introduces the vial in the liquid scintillation counter.     

A new method for measuring radioactivity in select areas of intact tissue sections.

A new technique is described for measuring radioactivity in select areas of intact tissue sections. The method, which makes use of a liquid scintillation counter, also makes possible identification of the studied zones by prestaining.     

Water or ice?--the challenge for invertebrate cold survival

The ecophysiology of cold tolerance in many terrestrial invertebrate animals is based on water and its activity at low temperatures, affecting cell, tissue and whole organism functions. The normal body water content of invertebrates varies from 40 to 90% of their live weight, which is influenced by water in their immediate environment, especially in species with a water vapour permeable cuticle. Water gain from, or loss to, the surrounding atmosphere may affect animal survival, but under sub-zero conditions body water status becomes more critical for overwinter survival in many species. Water content influences the supercooling capacity of many insects and other arthropods. Trehalose is known to maintain membrane integrity during desiccation stress in several taxa. Dehydration affects potential ice nucleators by reducing or masking their activity and a desiccation protection strategy has been detected in some species. When water crystallises to ice in an animal it greatly influences the physiology of nearby cells, even if the cells remain unfrozen. A proportion of body water remains unfrozen in many cold hardened invertebrates when they are frozen, which allows basal metabolism to continue at a low level and aids recovery to normal function when thawing occurs. About 22% of total body water remains unfrozen from calculations using differential scanning calorimetry (compared with ca 19% in food materials). The ratio of unfrozen to frozen water components in insects is 1:4 (1:6 for foods). Such unfrozen water may aid recovery of freezing tolerant species after a freezing exposure. Rapid changes in cold hardiness of some arthropods may be brought about by subtle shifts in body water management. It is recognised that cold tolerance strategies of many invertebrates are related to desiccation resistance, and possibly to mechanisms inherent in insect diapause, but the role of water is fundamental to them all. Detailed experimental studies are needed to provide information which will allow a more complete and coherent understanding of the behaviour of water in biological systems and aid the cryopreservation of a wide range of biological material.     

Experimental study on photocount statistics of the ultraweak photon emission from some living organisms

The hypothesis that biophotons display a high degree of coherence was tested by measuring photocount statistics (PCS) of the ultraweak photon emission from three living organisms (cucumber seedling, mungbean seedling and soybean rhizobium bacteroids) with a high-sensitivity single-photon counter. For comparison, the same experiments were performed for laser beam, randomized laser beam, chemiluminescence from autoxidation of luminol and the dark counts of the equipment. Photocount distributions, close to Poissonian, were observed for the three tested biological systems but not for the pure chemiluminescence of luminol.     

Determination of certain physical and chemical characteristics of the activating serum factor from preparturient women and women with habitual abortions

Follow-up investigation of the blood sera from preparturient women and women with habitual abortions showed the presence of a factor which has an activating effect on smooth muscle preparations because it causes the release of prostaglandins. Gel-chromatographic counter flow separation and microelectrophoresis of the blood sera have shown that the isolated serum factor is a water soluble glycopeptide with a molecular weight of about 2000.     

Über die Verwendung von künstlichen radioaktiven Isotopen zur Erzielung von lokalisierten biologischen Strahlenwirkungen

Summary Intratumoral injection of an artificial radioactive isotope (radiozinc), suspended in a solution of pectin: The author has previously reported on a method, which consists in the utilization of an artificial radioactive isotope for the production oflocalized biological radiation effects, by means of intraperitoneal injections of radiozinc (Zn⁶³) suspended in a suitably prepared solution of pectin. This procedure was applied to a small number of cases of cancer of the ovaries, with severe peritoneal extension, and yielded rather interesting therapeutic effects in these particularly bad conditions. Evidently this method can be applied also to malignant fumors of cavitary organs, such as the urinary bladder etc.The author investigated further, whether this procedure would also be suitable for interstitial radiotherapy, as previously presumed. Subcutaneous and intramuscular injections of the same suspension of radiozinc in pectin were thus performed on rabbits and were not followed by any diffusion of radioactivity outside the injected areas, as shown both by autoradiographs and controls of blood specimens with a counter. For the purpose of preliminary clinical investigation two cases of extended cancer of the uterine cervix recieved injections of 15 millicuries of radiozinc suspended in pectin within the tumor and its immediate surroundings (these cases were also submitted to the usual X-ray and radium-therapy). Specimens of blood and urine were checked with a counter and showed practically no radioactivity. Distinct fibrinous spots were observed a tew days later at the points of injection. This special form of interstitial radiotherapy will presumably gain some practical significance, as it offers the advantage that no foreign bodies have to be inserted in tissues as it is the case with radium needles and radon seeds, pectin being very well tolerated and resorbed by living tissues.     

Determination of certain physical and chemical characteristics of the activating serum factor from preparturient women and women with habitual abortions

Summary Follow-up investigation of the blood sera from preparturient women and women with habitual, abortions showed the presence of a factor which has an activating effect on smooth muscle preparations because it causes the release of prostaglandins. Gel-chromatographic counter flow separation and microelectrophoresis of the blood sera have shown that the isolated serum factor is a water soluble glycopeptide with a molecular weight of about 2000.     

A new method for measuring radioactivity in select areas of intact tissue sections

Summary A new technique is described for measuring radioactivity in select areas of intact tissue sections. The method, which makes use of a liquid scintillation counter, also makes possible identification of the studied zones by prestaining.The financial support of the Israel Cancer Association is gratefully acknowledged.Acknowledgment. We sish to thank Professor H. Nathan for his help and support and Professor J. Lenge for his constructive reading of the article.     

Molecular mechanisms of phagocytic uptake in mammalian cells

Phagocytosis is a highly conserved, complex process that has evolved to counter the constant threat posed by pathogens, effete cells and debris. Classically defined as a mechanism for internalising and destroying particles greater than 0.5 mum in size, it is a receptor-mediated, actin-driven process. The best-studied phagocytic receptors are the opsono-receptors, FcgammaR and CR3. Phagocytic uptake involves actin dynamics including polymerisation, bundling, contraction, severing and depolymerisation of actin filaments. Recent evidence points to the importance of membrane remodelling during phagocytosis, both in terms of changes in lipid composition and delivery of new membrane to the sites of particle binding. Here we review the molecular mechanisms of phagocytic uptake and some of the strategies developed by microbial pathogens to manipulate this process.     

AID and Apobec3G haphazard deamination and mutational diversity

Activation-induced deoxycytidine deaminase (AID) and Apobec 3G (Apo3G) cause mutational diversity by initiating mutations on regions of single-stranded (ss) DNA. Expressed in B cells, AID deaminates C → U in actively transcribed immunoglobulin (Ig) variable and switch regions to initiate the somatic hypermutation (SHM) and class switch recombination (CSR) that are essential for antibody diversity. Apo3G expressed in T cells catalyzes C deaminations on reverse transcribed cDNA causing HIV-1 retroviral inactivation. When operating properly, AID- and Apo3G-initiated mutations boost human fitness. Yet, both enzymes are potentially powerful somatic cell “mutators”. Loss of regulated expression and proper genome targeting can cause human cancer. Here, we review well-established biological roles of AID and Apo3G. We provide a synopsis of AID partnering proteins during SHM and CSR, and describe how an Apo2 crystal structure provides “surrogate” insight for AID and Apo3G biochemical behavior. However, large gaps remain in our understanding of how dC deaminases search ssDNA to identify trinucleotide motifs to deaminate. We discuss two recent methods to analyze ssDNA scanning and deamination. Apo3G scanning and deamination is visualized in real-time using single-molecule FRET, and AID deamination efficiencies are determined with a random walk analysis. AID and Apo3G encounter many candidate deamination sites while scanning ssDNA. Generating mutational diversity is a principal aim of AID and an important ancillary property of Apo3G. Success seems likely to involve hit and miss deamination motif targeting, biased strongly toward miss.     

Autoradiography and differential hemoglobin staining as aids to the study of fish hematology.

The confused state of the existing knowledge regarding the cell types in peripheral blood and hematopoiesis of fishes has been highlighted. Inadequacies of techniques presently used have been pointed out and the advantages of using Graham-Knoll's method for haemoglobin staining when counter stained with Giemsa together with autoradiography using tritiated thymidine have been demonstrated.     

Formation of coronary arteries sprouting from the primitive aortic sinus wall of the chick embryo

Summary The formation of coronary arteries in chick embryos was observed by scanning electron microscopy on injected casts as well as by transmission election microscopy. Usually, 2–4 primitive coronary arteries appear from the right aortic sinus below the level of the cusp margin, and 1–3 from the left one. As development proceeds, the arteries are generally reduced in number to form a single definitive coronary artery on each side. Canalization of the arteries seems to take place by partially degenerative changes of the primordia.Thanks are given to Prof. M. Mato, Department of Anatomy, Jichi Medical School, Tochigi for valuable suggestions, and Dr R.J. Adams for stylistic suggestions. The skillful technical assistance of MrS. Ide is acknowledged.