Important Inventions Research Articles

Invention and innovation in economic change

Purpose- In this paper we investigate the difference between invention and innovation. Since theories of invention are rare in the literature, this subject deserves the appropriation of proper attention. In the economics of competitive market, there is an important distinction between invention and innovation. Methodology- We use qualitative and historical-narrative methodology. An invention is devoid of economic value unless it is put into practical use and consumption. An abstract idea may be an important invention. But it takes an entrepreneur to transform the abstract invention into a marketable product. By “getting things done,” the entrepreneur produces economic value and thereby utility. Findings- The entrepreneur produces utilities by arranging, designing or re-organizing things in a new way that were not done before. On the other hand, the inventor creates ideas to produce something new that was inexistent beforehand. Conclusion- The task of inventor may seem more essential at first. However, as far as competitive economy is concerned, the function of innovative entrepreneur is determinant in economic change and development. An inventor becomes entrepreneur if endeavor in invention is transformed into labor in entrepreneurship.

A Study on HRM Practices of Employees on Printing Industry in Sivakasi

The history of printing goes back to the duplication of images by means of stamps in very early times. The use of round seals for rolling an impression into clay tablets goes back to early Mesopotamian civilization before 3000 BCE, where they are the most common works of art to survive, and feature complex and beautiful images. The printing press is considered one of the most important inventions in history. Human resource management (HRM or simply HR) is a function in organizations designed to maximize employee performance in service of their employer’s strategic objectives. HR is primarily concerned with how people are managed within organizations, focusing on policies and systems. HR departments and units in organizations are typically responsible for a number of activities, including employee recruitment, training and development, performance appraisal, and rewarding (e.g., managing pay and benefit systems). HR is also concerned with industrial relations, that is, the balancing of organizational practices with regulations arising from collective bargaining and governmental laws.

Systems for modern quality and business improvement

In 1924 Walter A. Shewhart of the Bell Telephone Laboratories developed the statistical control chart concept. This is usually considered the formal origin of the field of statistical quality control. The control chart is one of the most important technological inventions of the 20th century; it has a simple theoretical foundation, it is easy to use, it can be applied in a wide range of business, service and industrial settings, and it is a proven effective technique in providing the information critical to variability reduction and process improvement. This paper discusses the foundations of Shewhart’s work, and his influence on other leaders of the field, including Joseph Juran and W. Edwards Deming. The Shewhart cycle (Plan-Do-Check-Act, or PDCA) was popularized by Deming as a fundamental process improvement paradigm that evolved into the Define-Measure-Analyze-Improve-Control (DMAIC) process that is an integral part of the implementation of modern Six Sigma. Control charts have evolved in many directions beyond the basic Shewhart model, but they remain the key technical component of the field of statistical process control (SPC). We describe how SPC is an integral component of Six Sigma, and the critical role it plays in several steps of the DMAIC process. We conclude with a brief overview of some of the current research in the field.

INNOVATION, THE AGRICULTURAL BELT, AND THE EARLY GARDEN CITY

The emergence of the Garden City movement, inspired by Ebenezer Howard’s book To-morrow: a Peaceful Path to Real Reform (1898), subsequently published as Garden Cities of To-Morrow (1902), would have an enormous impact on future urban development and town- planning worldwide (e.g., Parsons and Schuyler 2002, 78; Ward 1992; Cooke 1978). Lewis Mumford claimed that the two most important inventions of the early twentieth century were the airplane and the Garden City (Mumford 1960). The Garden City model in many ways represents the antithesis to the historic city, as a model derived from smaller rural communities with a defined size, low densities, and a wealth of green space. Many subsequent urban models have expanded upon, altered, and diverged from Howard’s ideas. The Gar- den City has radically challenged the expectation that a city is a dense, vibrant, and largely hard-landscaped environment. In fact, urban environments developed over the last half-century have in many cases been dispersed, low-intensity, and soft-landscaped en- vironments, resulting in substantial changes to the way cities are constructed, managed, and inhabited.

John Michael Julius Madey

The inventor of the free-electron laser (FEL), John Michael Julius Madey, died of lung cancer on 5 July 2016 in Honolulu, Hawaii. He left an indelible mark on the international accelerator community. John Michael Julius Madey UNIV OF HAWAII AT MANOA/PHYSICS AND ASTRONOMY DEPTPPT|High resolutionJohn was born in Elizabeth, New Jersey, on 28 February 1943. In 1946 he and his family moved to a new house in Clark, where John grew up. His father owned an auto repair shop and instructed him and his older brother Jules in basic machine-shop skills. When John was 11, he and Jules studied together for their ham radio licenses from the Federal Communications Commission and provided morale communications for US Navy crewmen and civilian scientists stationed in Antarctica and their loved ones back home.John’s increasing fascination with the vacuum tubes used in the transmitters led him to learn everything there was to know about vacuum-tube technology. He was an avid builder of his own ham equipment, and the skills he developed served him well in his physics career. Howard Schrader, the brother of John’s next-door neighbor, owned one of the largest collections of vacuum tubes in the world. After hearing about the Madey brothers’ enthusiasm for the technology, Schrader, who was Princeton University’s official photographer, introduced them to John Wheeler and other faculty members.In 1960 John went to Caltech, where he received a BS in physics in 1964 and an MS in quantum electronics in 1965. While there he became deeply interested in whether the transition rate for bremsstrahlung could be amplified through stimulated emission. That curiosity continued when he went to Stanford University, where he earned a PhD in 1970 under the supervision of William Fairbank and conceived his most important invention: the FEL. Its bunched electron beam would pass through a periodic magnetic structure to stimulate the emission of light. In 1976, while working at Stanford’s High Energy Physics Laboratory, John and his team succeeded in demonstrating the FEL principle; they used a 24 MeV electron beam and a 5-meter-long wiggler magnet to amplify the beam from a carbon dioxide laser. By 1978 they had added mirrors to the system and increased the electron energy to 43 MeV, which allowed laser oscillations at a wavelength of 3.5 μm in the near-IR part of the optical spectrum. The power and efficiency were small—300 mW and 0.01%, respectively—but it was clear that the FEL scheme worked.In contrast to early FELs that used mirrors or optical cavities, today’s linac-based FELs, including SLAC’s Linac Coherent Light Source and the European XFEL, operate at much shorter wavelengths. They have proved indispensable for research in physics, chemistry, and biology because their highly intense, coherent electromagnetic radiation is tunable over a broad range of frequencies.In 1986 while still at Stanford, John became a professor of electrical engineering. Two years later he joined Duke University’s physics department, and the following year he transported his FEL research laboratory there from Stanford and continued to direct it for almost 10 years. John moved to the department of physics and astronomy at the University of Hawaii at Manoa in 1998 and built an FEL facility from scratch using some parts obtained from Duke. The facility provided a unique opportunity for hands-on training of graduate students in FEL science and technologies. John was a great mentor; working side by side with students, he imparted his knowledge and expertise.John held 13 patents on FEL-related technological inventions. A legal dispute over some of his patents led to a judgment in John’s favor. On 3 October 2002, in Madey v. Duke University, the Federal Circuit Court of Appeals ruled that the university was infringing on two of John’s patents because it was profiting from them beyond the experimental use “solely for amusement, to satisfy idle curiosity, or for strictly philosophical inquiry.” The historic case, which ended a 170-year-old practice in which scientists freely used patented technologies when working on basic research that had no commercial application, has been discussed and written about by many legal scholars around the world.Among the numerous awards and international recognitions that John received was the American Physical Society’s 2012 Robert R. Wilson Prize for Achievement in the Physics of Particle Accelerators. At the 2015 Nobel Symposium on Free-Electron Laser Research in Sigtuna, Sweden, he served as the keynote speaker.John will be remembered by his colleagues as the enthusiastic developer of the FEL and a prolific scientist of great drive and insight.© 2017 American Institute of Physics.

100 Jahre Einkristallzucht aus der Schmelze

AbstractIm August 1916 reichte der Deutsch‐Pole Jan Czochralski eine Publikation über die Wachstumsgeschwindigkeit von Metallkristallen bei der Zeitschrift für physikalische Chemie ein. Daher wird 1916 als das Jahr der Entdeckung des Czochralski‐Kristallzuchtverfahrens angesehen. Im Metall‐Laboratorium der AEG, wo Czochralski zunächst arbeitete, wurden seine Forschungsarbeiten nicht gebührend anerkannt, sodass er zur Metallbank und Metallurgischen Gesellschaft (später: Metallgesellschaft) nach Frankfurt wechselte, wo er bald zum Laborleiter und Oberingenieur aufstieg. In Frankfurt machte er sich mit Forschungen zu Metallen und technischen Legierungen rasch einen Namen. Die Entdeckung des Czochralski‐Kristallzuchtverfahrens gehört zu den wichtigsten technologischen Erfindungen des 20. Jahrhunderts, die aber erst in dessen zweiten Hälfte mit dem Aufstieg der Halbleiterindustrie ökonomische Bedeutung erlangte. Heute werden 95 % der Weltproduktion an Siliciumeinkristallen nach dem Czochralski‐Verfahren hergestellt. Der Umsatz der Halbleiter‐Industrie betrug 2015 etwa 335 Milliarden US‐Dollar, wobei die Kristallzucht nach dem Czochralski‐Verfahren jeweils der erste Schritt bei der Herstellung ist. Der größte Teil der heute gefertigten Siliciumeinkristalle hat einen Durchmesser von 300 mm. Die industrielle Produktion von Einkristallen mit 450 mm Durchmesser scheitert bisher nicht an technologischen, sondern an ökonomischen Problemen.

Analysis and Implementation of Data Mining Algorithms for Deploying ID3, CHAID and Naive Bayes for Random Dataset

Objectives: Effective data processing for fast retrieval of information has become a burning issue. A modern document contains not only text but images, video, audio as well. In this paper, a brief history of storage devices from the Vedic period to the world of digitization with some important inventions has been presented. Method/Statistical Analysis: It also includes the discussion on how data is transformed for the decision making process along with preprocessing techniques. Findings: A comparative analysis has been done of various techniques, their specific algorithms, uses, pros, limitations and applications where these can be implemented. It helps to give us an insight about these techniques. Finally experimental results on three different algorithms (Id3, CHAID, Naive Bayes) using Rapid Miner have been evaluated to compare their performance based on three parameters (accuracy, precision and recall). Applications/Improvements: The empirical results show the ID3 as more accurate than others with 95.95% accuracy while CHAID shows 89.11% and Naive Bayes classified 81.77% data accurately. *

Origin and Development of Knowledge on Inorganic Materials (Historical Overview)

The evolution of knowledge and inventions that contributed to the science of materials has been studied. The development of materials science in the ancient world involved the accumulation of intuitive inventions and the development of crafts. The antiquity established natural philosophy ideas about the nature of matter and divided all existent things into organic and inorganic worlds (Democritus, Epicurus, Aristotle). In the early Middle Ages, alchemy was widespread, with an idea of transmuting elements into gold. Although alchemical ideas were erroneous, they brought some benefits, contributing to the development of scientific experiment. The New Times marked the rapid development of fundamental sciences that promoted theoretical and practical materials science. This paper presents a chronology of the most important inventions and scientific concepts in a tabular form.

Unresolved Judicial Conflict and Critical Infrastructure

Choice of law affects legal outcomes at the core of Anglo-American law. This Article analyzes what electricity is, how the law regards it, and concludes by examining the confusion and inconsistency created by many courts. Even finishing second among the most important inventions in history (second behind only the movable type printing press) highlights the essential role of electricity in the American economy: Among the most important inventions in human history, electricity is the only one which also is essential and irreplaceable to operate seven other of the “top 50” inventions of all time: the Internet, computers, air-conditioning, radio, television, the telephone, and semiconductors.

The Modern Enterprise - Successor of Business Organization Forms in Ancient Rome and Medieval Europe

In recent years, researchers and practitioners are increasingly interested in the role and influence of the forms of business organization on the economy and society. Interpretations of the role of companies in the modern period, ranging from enthusiastic support (as the most important invention of capitalism, an explanation of the Western civilization’s expansion) to moderate and often critical positions, where the company is seen as a solution, not necessarily optimal, to market imperfections. On the other hand, we often ponder upon the explanation of political, administrative and infrastructural success of ancient Rome: the state or the enterprise (the private initiative)? Closer to our time, we rediscover with amazement that the "dark" Middle Ages are not at all dark and lacking in progress, at least in terms of capitalist organization and logic. The development of trade in the two poles of medieval Europe (the Mediterranean and the Balto-Scandinavian area), of industry and trade in the North-Western quadrant (Flanders and neighbouring regions), was concurrent with the improvement of organizational forms of business, with the diversity and flexibility of entrepreneurial or even corporate frameworks. Of course, the study of historical sources (ancient or medieval) cannot provide direct answers or solutions to the questions of modern society, because the challenges of today are rather different to those of the past. On the other hand, understanding history can help companies to build a more complete and a wiser enterprise functionality and role in the modern society, to reformulate the questions and to find new solutions. Our paper, with a clear juridical perspective on economic history, focuses on the organization of firms in ancient Rome and medieval Europe, tries to provide examples, useful interpretations and diverse solutions to the problems of contemporary society and economy.

激光诱导击穿光谱技术研究进展

激光诱导击穿光谱技术是激光技术的重大发明，因其能够对物质元素进行无损、高灵敏度、快速的定性与定量分析，成为污染物检测、食品安全检测、元素痕量分析等领域重要的技术手段。经过多年发展，激光诱导击穿光谱技术以其具有的独有技术优势，在多个领域表现出了巨大的潜在应用价值，并且国外同行已将这项技术应用到核电站安全监控、空间探索、工业检测等领域。相对于国外的研究进展，国内开展此项技术的研究起步较晚，尤其在应用领域存在较大差距。本文综述激光诱导击穿光谱技术的发展历程，概述该技术的基本原理，突出应用领域及其特点，并分析对检测结果的影响因素。 Laser-induced breakdown spectroscopy is an important invention. It has the characteristics of no damage, high sensitivity and rapid qualitative and quantitative analysis of material elements, so it has been widespread concern of pollutant monitoring, food safety inspection and trace element analysis etc. After years of development, the technology of laser-induced breakdown spectroscopy (LIBS) is given many technical advantages in the field of multiple with potential appliance value. The LIBS has been widely used abroad, such as nuclear power plant safety monitoring, space exploration and industrial inspection etc. However, study on LIBS in China started late; especially in the field of application, there is a big gap. It described the development of laser-induced breakdown spectroscopy, basic principles, application field and characteristics, and analysed the impact factors of testing result.

Developments in the management of diabetic ketoacidosis in adults: implications for anaesthetists

### Key points Diabetic ketoacidosis (DKA) is a medical emergency. The diagnostic triad is: 1. Ketonaemia ≥3.0 mmol litre−1 or significant ketonuria (more than 2+ on urine sticks) 2. Blood glucose >11.0 mmol litre−1 or known diabetes mellitus 3. Bicarbonate <15.0 mmol litre−1, venous pH <7.3, or both. DKA can occur in both type 1 and type 2 diabetes mellitus and, although preventable, it remains a frequent and life-threatening complication. Errors in the management of DKA are not uncommon and are associated with significant morbidity and mortality. The majority of mortality and morbidity in DKA are attributable to delays in presentation and initiation of treatment. Rapid recognition and treatment of DKA is critical. To overcome these concerns and to highlight current management strategies, the Joint British Diabetes Societies (JBDS) published guidelines in 2010. This was updated in consultation with the Intensive Care Society in September 2013.1 This article will review the pathophysiology of DKA and highlight the modern management of DKA that is relevant for anaesthetists. A summary of the JBDS guidelines pertinent to intensivists has been published.2 In England in 2010, there were 14 375 admissions to …

OCCURRENCE OF PLASTIC WASTE IN THE ENVIRONMENT: ECOLOGICAL AND HEALTH RISKS

Environmental threats posed in the environment by plastic production and plastic wastes continue to be a major problem today, closely connected with the increase of plastics consumption by the population. Moreover, little efforts are involved in some parts of the world associated to plastic waste collection, recycling and reuse. Considering all these prerequisites, the identification and discussion of risks generated by plastic production and waste in the environment are performed in this paper and some measures for plastic waste reduction were proposed. Although plastic polymers are not considered toxic, some residual monomers contained in the materials can be hazardous. Also, many chemical compounds used in the plastics manufacturing as additives, in particular plasticizers are dangerous to human health and the environment, along with some degradation products that may be released during the plastic life cycle. Bearing in mind the potential impacts and risks generated by these products in the environment and for humans, the paper highlights that the current requirements and tendencies are to reduce the need for plastic, the enhancement of recycling and recovering the waste, simultaneously with the replacement of plastic from fossil fuel with a continuous widening spectrum of biodegradable polymers. Bioplastics began to be recognized as a positive and important invention of chemical and plastics industry, providing many and varied opportunities for environmental impacts and risks abatement.

Reading Age Beyond Childhood

Reading Age Beyond Childhood Sari Edelstein (bio) Why have scholars of American literature neglected age, broadly defined, as a critical lens and as an explicit subject of nineteenth-century culture? The blossoming field of childhood studies masks a larger reticence about age. Indeed, humanities scholars’ nearly exclusive attention to children has limited our focus to a single stage of life, the period fetishized by conservative investments in reproductive futurity and heteronormativity. This uneven focus on children and children’s cultures seemingly privileges young people’s lives as the most politically significant and worthy of historical and literary recovery. Even as critics may dismantle what Lauren Berlant called the “idealization of the child as citizen,” there is nonetheless an ideological problem when we fail to complement projects on American youth by considering age more broadly.1 In other words, childhood studies’ increasing prominence creates the illusion that we are discussing age, but in fact, the disproportionate attention to youth risks reifying childhood as the most appealing and meaningful site of inquiry. Moreover, this scholarship tends to demarcate development and vulnerability as particular to childhood when such conceptual terms may be usefully applied to any age. My goal here is not simply to urge scholars to add age to the standard list of identity categories that have attracted our attention. Rather, I argue that these other measures of social location (race, gender, sexuality, class, ability) are largely legible through the seemingly more natural and essential identity defined by age.2 That is, age ideology operates in tandem with discourses of power and naturalizes existing hierarchies. For example, the discourse of age conditions how we conventionally understand gender, enshrining old men as sources of wisdom while women are instructed in what critic [End Page 122] Kathleen Woodward calls the “pedagogy of mortification,” which teaches them invisibility after their reproductive years have passed.3 Similarly, quantitative, numerical age provides an ostensibly objective basis for the false binary between disabled and able bodies, as it is largely through age that mainstream science measures whether individuals are bodily appropriate and developmentally on schedule. During the nineteenth century, numerical age became a primary identity coordinate. The 1850 census was the first to ask respondents to include numerical age, and it was also the first census to render the pseudo-scientific taxonomy of race even more complex, suggesting how age and race simultaneously became crucial sites in a regime centered on bodily classification. Additionally, universal white male suffrage gradually became linked with the age of twenty-one rather than with property ownership. Alongside the state’s obvious biopolitical investment in numerical age as a relevant quantifier of political maturity and a key statistic for assessing the national population, numerous institutions, including schools and hospitals, were organizing around age. Age categories also became markets; publishers catered to specific age groups, and periodical culture increasingly interpolated readers within specific age demographics. Collectively, these developments signal how chronological age was integral to what Judith Treas calls a “stratification regime,” which standardized the course of American lives.4 Historians offer conflicting explanations for why age acquired heightened significance. Some link this shift to rising market capitalism, which devalued older people’s wisdom and instead favored the efficiency typically associated with youth. George Miller Beard’s American Nervousness (1881), for example, links aging not only to declining productivity but also to diminished creativity. He laments, “I find no record of any very important invention conceived and developed after the age of 60. Edison, with his three hundred patents, is not the only young inventor. All inventors are young.”5 Others [End Page 123] read the increased attention to age as a response to basic demographic changes; there were more people over sixty-five at the end of the nineteenth century than the nation had ever seen before. Whatever the explanation, we should recognize and study the nineteenth century’s second half as the moment that gave rise to our modern culture of age. In its insistence on age benchmarks and its disdain for aging itself, nineteenth-century culture laid the groundwork for contemporary concerns about the physiological, aesthetic, and economic costs of growing older. Moreover, anxieties about inappropriate aging permeated periodical culture and...

The Reality of Legitimacy Alternatives of financial Derivatives in the Light of the Islamic Financial Engineering Products

Financial Derivatives are regards as the most important products of financialengineering and the most important financial inventions and innovations reachedby the centers of research and development. Derivatives are financialinstruments its value linked with certain financial tool or any index or goodwhich help to buy and sell financial risks in the financial markets. The optioncontracts, future contracts, future and swap contracts are the most importanttypes of financial derivatives and the most current traded in the financialmarkets. But the dealing by these tools in terms of legitimacy is not permissiblebecause they contradict mildly with the Sharia, and they involve suspicioustransactions of bribery and gambling. However, there are legitimate alternatives,which are proved to be efficient, and which can replace these derivatives, likecontract of peace, the rent contract, the deferred sale, and option condition.

Ancient road transport devices: Developments from the Bronze Age to the Roman Empire

The development of transportation systems has significantly enhanced the welfare and modernization of society. Wooden vehicles pulled by animals have been used for land transportation since the early Bronze Age. Whole-body gharries with rigid wheels pulled by oxen appeared in Crete by 2000 BC or earlier. Horses originating from the East were depicted in early Cretan seal-rings of the same period. The two-wheeled horsedrawn chariot was one of the most important inventions in history. This vehicle provided humanity its first concept of personal transport and was the key technology of war for 2000 years. Chariots of Mycenaean and Archaic Greece with light and flexible four-spoked wheels acting as spring suspensions were depicted in vase paintings. The development of this vehicle incorporated the seeds of a primitive design activity and was important for engineering. The Trojan horse since 1194 BC and the helepolis since 700 BC were the first known machines on a wheeled base transported by horses or self-powered. Ancient engineers invented bearings lubricated with fat, and Romans introduced the ancestors of ball bearings for their wagons and carts. The historic evolution of wheeled transportation systems, along with early traction, suspension, and braking systems, is presented in this paper. Analytical and numerical methods are incorporated to analyze the most conceivable loading situations of typically reconstructed wheeled transportation systems in ancient times. Traction requirements both for horse-driven machines and the power for internal motors are also analyzed. This study can serve as a basis for further development of detailed reconstruction of transportation systems in antiquity.

Pectoral fin of the Paleozoic shark, Cladoselache: new reconstruction based on a near-complete specimen

One of the most important inventions in vertebrate evolution is paired fins. Recent findings from studies of developmental genetics have shown that some, but not all, of the developmental mechanism...

Reflections

Reflections Eileen Boris (bio) and Elizabeth Currans (bio) Working women, especially Negro women, labor not only under the disadvantages imposed by the feminine mystique, but under the more pressing disadvantages of economic discrimination. Gerda Lerner to Betty Friedan, 196341 It is a measure of the impact of Gerda Lerner—the activist, memorialist, writer, historian, feminist, and institution builder who passed away on January 2, 2013, at the age of ninety-two—that both the American Historical Society and the Organization of American Historians have celebrated her scholarship and life since her death with multiple panels. In 1981 she served as president of the oah, which named the Lerner-Scott Prize for the best dissertation in women’s history after her. Lerner brought to the study of history an understanding of class and race and the willingness to speak out for what she believed was right, as seen in her comments to Betty Friedan, whom she knew from left circles, on the publication of The Feminine Mystique. Unlike Friedan, Lerner eventually, in Fireweed: A Political Autobiography (2002; a book Eileen stayed up all night reading when traveling back from the Berkshire Conference, where it was released), would admit to a communist past, which included involvement with the Congress of American Women, which organized working-class mothers and housewives around the point of daily activities that theorists name social reproduction. Lerner never forgot the triple (race, gender, and class) oppression of black women. Perhaps that is why Eileen found her work so inspiring. Around 1971 Gerda came to Brown, where Eileen was a graduate student, to talk about The Grimke Sisters from South Carolina (1967). What really made a difference for Eileen was teaching Black Women in White America as soon as she could after it was published in 1972, a book that showed the way to transform US women’s history through the experiences and thought of black women. Through pioneering essays on class divisions between women and on the significance of domestic labor, collected in The Majority Finds Its Past (1979), Lerner offered strands that Eileen and many others would weave into an intersectional approach to women’s labors. Thus, historian Dolores Janiewski, a former student [End Page 27] of Gerda’s at Sarah Lawrence who now teaches in New Zealand, underscored Gerda’s recognition of the burdens of the home when recounting contrasting responses to a question on the most important invention for the liberation of women that Gerda posed to her class. While the students said “the pill,” Gerda replied, “the laundromat because now men could do the laundry.” Gerda sparked the creation of the Coordinating Committee of Women in the History Profession (ccwhp, now the Conference Group on Women’s History, the cgwh), for which Eileen would serve as newsletter editor and president over two decades later. She had the privilege of editing Gerda’s personal narrative for a collection that traced the history of women’s history through the voices of ccwh leaders. As Gerda concluded her contribution, “We have proven, over and over again, that women make history and have always made history. In so doing, we have had to challenge the exclusionary and outdated patriarchal structures of academic institutions. Life and thought have merged; transforming knowledge has led us to transform institutions.”42 Both the symposium in this issue and recollections elsewhere, as well as those of you who shared your thoughts with us, underscore Gerda’s sometimes difficult but always galvanizing presence.43 One of the challenges of memorializing is acknowledging a person’s accomplishments, attending to her uniqueness, and yet avoiding creating an image of a remarkable figure untouched by context and outside of the vibrant collective process of knowledge-making. Gerda Lerner was a prolific and insightful writer, an organizer both in and outside of academic institutions, and a dynamic personality, described as “charismatic,” “fierce,” “outrageous,” “independent,” and possessing “chutzpah” by those who knew her well. She was also part of numerous intellectual and activist movements that helped shape her as a leader and thinker. She was a friend and colleague who talked with those she allied herself with for hours and hours, making sense out of circumstances and planning...

SISTEM ORTONORMAL DALAM RUANG HILBERT

Hilbert space is one of the important inventions in mathematics. Historically, the theory of Hilbert space originated from David Hilbert’s work on quadratic form in infinitely many variables with their applications to integral equations. This paper contains some definitions such as vector space, normed space and inner product space (also called pre-Hilbert space), and which is important to construct the Hilbert space. The fundamental ideas and results are discussed with special attention given to finite dimensional pre-Hilbert space and some basic propositions of orthonormal systems in Hilbert space. This research found that each finite dimensional pre- Hilbert space is a Hilbert space. We have provided that a finite orthonormal systems in a Hilbert space X is complete if and only if this orthonormal systems is a basis of X.

Neuregulin Signaling in Pieces—Evolution of the Gene Family

Paracrine and juxtacrine signaling via proteins expressed on the cell surface are an integral part of metazoan biology. More than one-half billion years ago epidermal growth factor (EGF) and its cognate receptor formed a functional binding partnership, which has been conserved through evolution in essentially all eubilaterate members of the animal kingdom. Early chordates spawned offspring of these seminal genes to begin the creation of new gene families and an expanded cell-cell signaling network, which included the Neuregulin (NRG) ligands and the erbB receptors. First appearance of ancestral NRG, represented in a NRG4-like gene in the lancelet Branchiostoma floridae, appears to have: 1) occurred in the common chordate ancestor prior to the divergence of lancelets (amphioxus), and; 2) antedated the formation of the receptor gene family. Orthologues of NRG1 and multiple erbB receptors found in the sea lamprey Petromyzon marinus suggest that several key events, which were required to expand and diversify these gene families, occurred in the common ancestor of agnathostomes and jawed vertebrates. These important inventions surely played major roles in the acquisition of multiple apomorphic features of the emerging vertebrate lineage.