Synthesis of ovulation-inhibiting compounds; structure-activity relationship.

We describe the synthesis of some new derivatives of benzo(4, 5)cyclohepta(1, 2-b)thiophene which inhibit ovulation and the secretion of luteinizing hormone (LH) in the rat. We also describe the relationship between the structure and activity of these compounds.     

A sensitive and inexpensive high-performance liquid chromatographic assay for tyrosine hydroxylase

We describe a highly sensitive assay method for tyrosine hydroxylase (TH) using high-performance liquid chromatography with amperometric determination. This assay method could be applicable to any tissues with low enzyme activity, such as rat cerebellum. We also describe the kinetic properties of TH in rat cerebral cortex.     

A sensitive and inexpensive high-performance liquid chromatographic assay for tyrosine hydroxylase

Summary We describe a highly sensitive assay method for tyrosine hydroxylase (TH) using high-performance liquid chromatography with amperometric determination. This assay method could be applicable to any tissues with low enzyme activity, such as rat cerebellum. We also describe the kinetic properties of TH in rat cerebral cortex.     

The extracellular matrix of theDictyostelium discoideum slug

In this review, we detail the current understanding of the extracellular matrix (ECM) of the migratory slug phase of the cellular slime mould,Dictyostelium discoideum. We describe some structural and non-structural molecules which comprise the ECM, and how these molecules reflect both plant and animal ECM systems. We also describe zones of the multicellular slug that are known to make ECM components, including the role of the prestalk cells and the slug epithelium-like layer. Finally, we review the contributions of studies on mutant to our understanding of the ECM ofD. discoideum, and relate this to differentiation and development in more complex eukaryotic systems.     

SONOS自持半导体存储器:记忆时间可靠性与低编程电压

降低编程电压，同时仍保持十年的数据记忆时间，一直是多晶硅－氧化硅－硅（SONOS）研究人员面临的一个巨大挑战。本文介绍SONOS可自持存储器器件设计和降低编程电压方面的进展，硅－氧化硅界面态的退化损害SONOS自持半导体存储器记忆时间和长期可靠性。首次应用在SONOS器件制作工艺上的双步高温氘退火技术，与传统的氢退火相比，显著提高了器件的耐久性能和记忆时间可靠性。我们研制成功－9伏／＋10伏（1毫秒）可编程SONOS存储器，在摄氏85度，一千万个擦除／写入操作后，仍能确保十年的记忆时间，本文介绍编程电压降低方面的设计考虑，制作工艺的优化，描述实验过程和SONOS器件的测试，以及用于SONOS自持存储器动态性能测试的基于可编程门阵列的测量系统。     

Forecasting stock market volatility using (non-linear) Garch models

In this paper we study the performance of the GARCH model and two of its non-linear modifications to forecast weekly stock market volatility. The models are the Quadratic GARCH (Engle and Ng, 1993) and the Glosten, Jagannathan and Runkle (1992) models which have been proposed to describe, for example, the often observed negative skewness in stock market indices. We find that the QGARCH model is best when the estimation sample does not contain extreme observations such as the 1987 stock market crash and that the GJR model cannot be recommended for forecasting.     

Morphological differentiation of neuroblastoma by 1 methyl cyclohexane carboxylic acid (CCA) and some C1 derivatives]

We describe the induction of neuroblastoma morphological differentiation by 1 methyl cyclohexane carboxylic acid (CCA) and by some C1 derivatives of CCA. This induction proceeds in a medium which allows, in the absence of inducer, a normal growth of neuroblastoma cells and contains 7.5% fetal Calf serum. In order to establish a clear-dose response relationship and to compare the relative potencies of different drugs, the morphological changes were assessed by examining "long neurite-bearing cells".     

Detection of pyrimidine 5'-nucleotidase deficiency using 1H- or 31P-nuclear magnetic resonance

We describe here a further Japanese family with pyrimidine 5'-nucleotidase (P5'N) deficiency diagnosed using a nuclear magnetic resonance (NMR) spectrum, in Kumamoto prefecture where two families having the disease have been reported before. The specific spectra in 1H-NMR of P5'N deficient erythrocytes were due to three methyl protons of CDP-choline at 3.22 ppm and to H-2, H-8 and ribose-1' of pyrimidine nucleotide phosphate(s) in the lower fields (at 5.82 and 8.00 ppm). The other specificities in 31P-NMR spectra were due to CDP-choline, CDP-ethanolamine and UDP-glucose. Those spectra were not detected in other types of hemolytic anemia.     

The life cycle of neutral lipids: synthesis, storage and degradation

Triacylglycerols (TAGs), steryl esters (SEs) and wax esters (WEs) form the group of neutral lipids. Whereas TAGs are present in all types of cell, the occurrence of SEs in prokaryotes is questionable, and the presence of WEs as storage molecules is restricted to plants and a few bacteria. Here, we summarize recent knowledge on the formation, storage and degradation of TAGs and SEs in various cell types. We describe the biochemical pathways involved in TAG and SE synthesis and discuss the subcellular compartmentation of these processes. Recently, several novel enzymes governing the metabolism of storage lipids have been identified and characterized. Regulatory aspects of neutral lipid storage are just beginning to be understood. Finally, we describe consequences of defects in neutral lipid metabolism. Since severe diseases like atherosclerosis, obesity and type 2 diabetes are caused by lipid accumulation, mechanisms underlying neutral lipid synthesis, depot formation and mobilization are of major interest for curing such diseases that are increasingly associated with modern civilization. Received 18 January 2006; received after revision 7 March 2006; accepted 16 March 2006     

The puzzle of half-integral quanta in the application of the adiabatic hypothesis to rotational motion

We present and discuss an interesting and puzzling problem Ehrenfest found in his first application of the adiabatic hypothesis, in 1913. It arose when trying to extend Planck׳s quantization of the energy of harmonic oscillators to a rotating dipole within the frame of the old quantum theory. Such an extension seemed to lead unavoidably to half-integral values for the rotational angular momentum of a system (in units of ℏ). We present the problem in its original form along with the (few) responses we have found to Ehrenfest׳s treatment. After giving a brief account of the classical and quantum adiabatic theorem, we also describe how Quantum Mechanics provides an explanation for this difficulty.     

The coagulation of insect hemolymph

In contrast to both vertebrates and non-insect arthropods, little is known about the coagulation of hemolymph (hemostasis) in insects. We discuss the integration of the hemostatic response with other branches of the insect immune system. We also describe the present stage in the characterization of both soluble and cellular factors that contribute to hemostasis in insects. The factors of the well-characterized clotting cascades of vertebrates, primitive chelicerates and crustaceans are used to assess the implications of sequencing the whole Drosophila genome for searching candidate genes involved in hemostasis. Some striking similarities between blood clotting in vertebrates and the reaction of insect cells involved in hemolymph coagulation have implications for a phylogenetic comparison of hemostasis between divergent animal classes.     

Scientists’ attitudes on science and values: Case studies and survey methods in philosophy of science

This article examines the relevance of survey data of scientists’ attitudes about science and values to case studies in philosophy of science. We describe two methodological challenges confronting such case studies: 1) small samples, and 2) potential for bias in selection, emphasis, and interpretation. Examples are given to illustrate that these challenges can arise for case studies in the science and values literature. We propose that these challenges can be mitigated through an approach in which case studies and survey methods are viewed as complementary, and use data from the Toolbox Dialogue Initiative to illustrate this claim.     

A microquantitative method for investigating the interaction between labeled lectins and the surface membranes of human lymphocytes using a semi-automatic harvesting machine

We describe a simple, rapid and economical method for the study of the interaction of labeled lectins and the surface membranes of human lymphocytes using a semi-automatic harvesting machine (Titertek Multiple Cell Harvester). The procedure requires both small numbers of cells and small amounts of lectin, moreover it reduces the number of experimental steps required.     

Bioportide: an emergent concept of bioactive cell-penetrating peptides

Cell-penetrating peptides (CPPs) have proven utility for the highly efficient intracellular delivery of bioactive cargoes that include peptides, proteins, and oligonucleotides. The many strategies developed to utilize CPPs solely as pharmacokinetic modifiers necessarily requires them to be relatively inert. Moreover, it is feasible to combine one or multiple CPPs with bioactive cargoes either by direct chemical conjugation or, more rarely, as non-covalent complexes. In terms of the message-address hypothesis, this combination of cargo (message) linked to a CPP (address) as a tandem construct conforms to the sychnological organization. More recently, we have introduced the term bioportide to describe monomeric CPPs that are intrinsically bioactive. Herein, we describe the design and biochemical properties of two rhegnylogically organized monometic CPPs that collectively modulate a variety of biological and pathophysiological phenomena. Thus, camptide, a cell-penetrant sequence located within the first intracellular loop of a human calcitonin receptor, regulates cAMP-dependent processes to modulate insulin secretion and viral infectivity. Nosangiotide, a bioportide derived from endothelial nitric oxide synthase, potently inhibits many aspects of the endothelial cell morphology and movement and displays potent anti-angiogenic activity in vivo. We conclude that, due to their capacity to translocate and target intracellular signaling events, bioportides represent an innovative generic class of bioactive agents.     

How to Fix an Election Honestly! Ivan Petrov Salabashev's Novel Voting Procedure in Bulgaria, 1879–1880

In this article, using archival sources we show how mathematical knowledge and methods helped to solve the problem of the election of the first exclusively Bulgarian government in the peaceful election in 1879 and 1880. We will describe the situation in Bulgaria, and especially the role of the mathematician, politician and financier Ivan Petrov Salabashev (1853–1924).     

Circles in spermatocyte chromatin loops. Electron microscopy and AgAs-NORs studies.

We describe the production of circles in chromomeric loops during the pachytene stage of the spermatocytes. These circles are found attached to chromatin or already free in the nucleoplasm. Each circle measures an average of 3700 A in circunference. We suggest that such circles might indicate the presence of tandem repetitions.