Work Of Earlier Investigators Research Articles

Experimental study on condensation heat transfer in vertical helically coiled tubes

In the present experimental study, condensation of steam inside helically coiled tubes was investigated. Three helical coils of coil diameter 110, 135 and 160 mm were tested. The effect of mass flux, coil curvature ratio and temperature difference between steam and tube inner wall on the condensation heat transfer coefficient were analysed. The condensation heat transfer coefficient increases with the increase in the value of mass flux. Temperature difference has substantial effect on the heat transfer coefficient. For the first time, the effect of coil curvature ratio on condensation heat transfer is studied and discussed in the paper. It is found that helical coil having greater coil curvature ratio has high values of condensation heat transfer coefficient in comparison to a low curvature ratio. Experimental results are compared with the work of earlier investigators. A new empirical correlation is developed to predict the condensation heat transfer coefficient.

Experimental study on condensation heat transfer in vertical helically coiled tubes

In the present experimental study, condensation of steam inside helically coiled tubes was investigated. Three helical coils of coil diameter 110, 135 and 160 mm were tested. The effect of mass flux, coil curvature ratio and temperature difference between steam and tube inner wall on the condensation heat transfer coefficient were analysed. The condensation heat transfer coefficient increases with the increase in the value of mass flux. Temperature difference has substantial effect on the heat transfer coefficient. For the first time, the effect of coil curvature ratio on condensation heat transfer is studied and discussed in the paper. It is found that helical coil having greater coil curvature ratio has high values of condensation heat transfer coefficient in comparison to a low curvature ratio. Experimental results are compared with the work of earlier investigators. A new empirical correlation is developed to predict the condensation heat transfer coefficient.

The pioneering of intracytoplasmic sperm injection: historical perspectives.

Intracytoplasmic sperm injection (ICSI) has often been heralded as a ground-breaking technique that has transformed the treatment of couples with infertility. By injecting a single spermatozoon into the cytoplasm of the oocyte, ICSI bypasses the zona pellucida and increases the chances of fertilization and subsequent embryo development, independent of semen parameters. Ever since the first live births using ICSI were reported in 1992, ICSI has become the mainstay of treating male factor infertility as well as overcoming fertilization failure associated with conventional in vitro insemination. Today, ICSI is utilized in nearly 66% of all assisted reproductive treatments worldwide and has resulted in the birth of millions of babies. The primary goal of this review is to provide historical perspectives about the pioneering of ICSI. We begin by highlighting the scientific work of early investigators who elucidated the mechanisms central to mammalian fertilization. Furthermore, we briefly discuss how these findings contributed to the development of IVF for the treatment of infertility. We then emphasize the shortcomings of IVF in treating severe forms of male factor infertility and enumerate the micromanipulation techniques that were developed to circumvent these shortcomings. Finally, we indicate how the inadequacies of these micromanipulation techniques lead to the inception, application and popularity of ICSI.

The fertile ground of Hell’s carnival: Charles T. R. Bohannan and the US Army’s Counter Intelligence Corps’ investigations of war criminals, collaborators, and the Huk, in the Philippines 1945–1947

ABSTRACTInsurgencies thrive in regions where government legitimacy is absent. In the post-war Philippines, Captain Charles T. R. Bohannan of the Army’s Counter Intelligence Corps became actively aware of this dynamic. Bohannan is best known for his later work with Edward Lansdale and Ramon Magsaysay in defeating the Huk Rebellion (1950–1954). Here the author examines Bohannan’s early investigative work against Japanese war criminals, wartime Filipino collaborators, and the rising threat of communist subversion most associated with the Huk. All of these experiences fed into what would be the successful campaign against the Huk, chronicled in his seminal work, Counter Guerrilla Operations: The Philippines Experience, and offers lessons on the investigative (as opposed to tactical or psychological) nature of effective counter-insurgency work, as it relates to both legitimacy in governance and the rise of insurgencies.

Development of experimental heat transfer correlations using Newtonian fluids in helical coils

The experimental work was carried out using water, 10 and 20 % glycerol–water mixture as Newtonian fluids under isothermal and non-isothermal conditions in helical coils. The experiments were performed in laminar and turbulent flow regimes using four helical coils of coil curvature ratios as; δ = 0.055, 0.064, 0.0685 and 0.0757. For the first time, an innovative heat transfer correlations in terms of new dimensionless number ‘M’ are developed based on 135 and 183 tests conducted under isothermal and non-isothermal conditions. The developed heat transfer correlations were compared with the work of earlier investigators and are found to be in good agreement. Hence, M number could be used for characterization of fluid flow in helical coils for any types of fluids which is significant. Also, comparison of Nusselt numbers for water and glycerol–water mixtures under different experimental conditions is presented in this paper. It was observed that as helix diameter increases, Nusselt number decreases due to decrease in centrifugal force.

Experimental and CFD investigation of convective heat transfer in helically coiled tube heat exchanger

Experimental studies on isothermal steady state and non-isothermal unsteady state conditions were carried out in helical coils for Newtonian as well as for non-Newtonian fluids. Water and glycerol–water mixture (10 and 20% glycerol) were used as Newtonian, and 0.5–1% (w/w) dilute aqueous polymer solutions of Sodium Carboxy Methyl Cellulose (SCMC) and Sodium Alginate (SA) as non-Newtonian fluids are used in this study. These experiments were performed for coil curvature ratios as δ=0.0757, 0.064 and 0.055 in laminar and turbulent flow regimes (total 258 tests). The CFD analyses for laminar and turbulent flow were carried out using FLUENT 12.0.16 solver of CFD package. The CFD calculation results (Nui, U, T2 and Two) for laminar and turbulent flow are compared with the experimental results and the work of earlier investigators which were found to be in good agreement. For the first time, an innovative approach of correlating Nusselt number to dimensionless number, ‘M’, Prandtl number and coil curvature ratio using least-squares power law fit is presented in this paper which is not available in the literature. Several other correlations for calculation of Nusselt number for Newtonian and non-Newtonian fluids, and two correlations for friction factor in non-Newtonian fluids (based on 78 tests and 138 tests) are proposed. These developed correlations were compared with the work of earlier investigators and are found to be in good agreement.

Nicholas Lechmere Tilney, M.D. (1935–2013)

Nicholas Lechmere Tilney, M.D. (1935–2013)

Predictive value of preoperative serum CA-125 levels in patients with uterine cancer: The Asian experience 2000 to 2012

ObjectiveMuch of the early investigative work on the usefulness of preoperative serum CA-125 levels in identifying patients with early-stage endometrial carcinoma who have occult metastases were carried out in Europe and the United States. This article reviews CA-125 as a possible index for determining the need for full surgical staging, from the results of large medical centers in Asia, particularly Taiwan and Korea.MethodsA Medline search was performed using CA-125 and endometrial cancer as index words from 1981 to 2012. Those publications felt to be the most important especially from institutions from Asia since 2000 were identified in this review.ResultsMost articles that analyzed the utility of serum CA-125 levels as predictive marker for disease extent or prognosis in uterine cancer used univariate and multivariable logistic regression analysis, and performed receiver operative curves to find the best cut-off values. The main factor of interest was whether clinicians can stratify patients that need lymphadenectomy in early stage disease. Suggested optimal cut-off value ranged from 20 to 210 U/mL. Not only preoperative CA-125 level, but myometrial invasion status by magnetic resonance imaging was the most significant combined parameter for predicting disease extent.ConclusionElevated CA-125 in patients with apparent early-stage disease is clearly a risk factor for the presence of extra-uterine disease although the optimal cut-off levels vary. The evolution of clinical investigations over the past decade, particularly in Asia, suggests employment of the test in a more focused manner to identify high risk patients preoperatively.

Experimental studies on heat transfer to Newtonian and non-Newtonian fluids in helical coils with laminar and turbulent flow

Experimental studies on isothermal steady state and non-isothermal unsteady state conditions were carried out in helical coils for Newtonian and non-Newtonian fluids. Water, glycerol–water mixture as Newtonian fluids and dilute aqueous polymer solutions of sodium carboxymethyl cellulose (SCMC), sodium alginate (SA) as non-Newtonian fluids were used in this study. These experiments were performed for coils with curvature ratios δ=0.0757, 0.064 and 0.055 in laminar and turbulent regimes. An innovative approach of correlating Nusselt number to dimensionless number ‘M’ for Newtonian fluids based on experimental data is presented which is not available in the literature. Several correlations for the first time are proposed based on heat transfer data generated from the experiments performed for Newtonian fluids under isothermal and non-isothermal conditions (total 138 tests). These developed correlations were compared with the work of earlier investigators and were found in good agreement. Further, comparison of overall heat transfer coefficient Uo, and Nusselt numbers for Newtonian and non-Newtonian fluids under isothermal and non-isothermal conditions (total 276 tests) is presented in this paper. From the experimental results, it was found that overall heat transfer coefficient and Nusselt numbers for water are higher than glycerol–water mixture and non-Newtonian fluids. It was also observed from experimental results that as helix diameter increases, overall heat transfer coefficient and Nusselt numbers of both fluids decreases for the same flow rates.

The early years of Toxoplasma research: What’s past is prologue

In the century since the first description of Toxoplasma gondii history and circumstance have led scientists to define this organism in diverse contexts. From its discovery by researchers shaped by early 20th century versions of the germ theory to its more recent roles as an important globally distributed pathogen and a model apicomplexan, our definitions of Toxoplasma are as much a reflection of our frame of reference as they are an absolute definition of this organism. Although these transformations act as portals for new avenues of investigation, the essential questions that inform current research are founded in the work of early investigators who studied Toxoplasma.

Inside and outside the dry stone walls: revisiting the material culture of Great Zimbabwe

Abstract‘Any study of Great Zimbabwe has to rely a great deal on re-examining and re-assessing the work of early investigators, the men who removed all the most important finds from the ruins and stripped them of so much of their deposits’ (Garlake 1973: 14). The authors have here done us a great service in reviewing the surviving archaeological evidence from this world famous site. They challenge the structuralist interpretation – in which different parts of the site were allocated to kings, priests, wives or to circumcision rituals – and use the architectural, stratigraphic and artefactual evidence accumulated over the years to present a new sequence. The early enclosures on the hill, the Great Enclosure and the valley enclosures now appear as the work of successive rulers, each founding a new residence and power centre in accord with Shona practice.

The Telome Theory

Morphologists have long been concerned with the fundamental nature of the vascular plant body-with the relationships between root, stem and leaf, and with the origin of reproductive structures. Attempts at analysis on the basis of either formal or phyletic morphology have given rise to a number of theories dealing with the organization of the plant body. Those related to the flowering plants are summarized by Arber (1930) and need not concern us here, since they are of historical interest only. A theory which encompasses a consideration of all vascular plants, and which is based primarily upon studies of the lower Tracheophyta, recent and fossil, has had greater vitality-so much so, indeed, that it has permeated the thinking of many morphologists and paleobotanists to a degree not realized by those who have not followed the literature in these fields. This is the telome theory, perhaps better termed the " telome concept". Among other aspects the telome concept has assisted in a clarification of our ideas on the relationships between root, stem and leaf, and emphasizes that the plant body is an axis, with a descending portion, the root, and an aerial portion, the shoot, whose appendages are merely modified parts of the stem. Before considering the telome theory itself, it is desirable to point out that, like many another concept, it did not arise de novo, but was foreshadowed by the work of earlier investigators. Reference will repeatedly be made to a fundamental principle advocated by all of these workers which is an essential part of the telome theory itself. This is the principle of overtopping, shown diagrammatically in its simplest form in Fig. 1. This principle involves the belief that the oldest method of branching was dichotomous (a dichopodium). If, at each fork, one of the two branches becomes stronger than the other, a sympodium will result, with an apparent main axis composed of one of the two forks. Continued development of the main axis results in a monopodium which gives off

Historical review of microbend fiber-optic sensors

This paper traces microbend sensors from the early investigative work into initial applications to measure many different parameters, through advanced prototype development and commercial hardware. Advantages and disadvantages of microbend sensors are discussed. >

Added Mass and Damping for Cylinder Vibrations Within a Confined Fluid Using Deforming Finite Elements

Added mass and fluid damping coefficients for vibrations of an inner cylinder that is enclosed by a concentric outer cylinder are determined by finite element analysis of the unsteady, laminar, incompressible flow in the annulus. Continuously deforming space-time finite elements are used to track the moving cylinder and the changing shape of the space domain. For small cylinder vibration amplitudes, the present results agree well with the work of earlier investigators who solved the linearized Navier-Stokes equations on a fixed mesh. Fluid damping coefficients are shown to increase with vibration amplitude. Added mass coefficients may either increase or decrease with increasing vibration amplitude.

Analysis of Acoustooptic Diffraction by Adjacent Ultrasonic Beams Using Multiple Plane-Wave Scattering Techniques

Abstmct-Plane-wave multiple-scattering theory is used to analyze scattering in the Raman-Nath regime for adjacent ultrasonic beams of frequency ratio 1:m. The variation of the scattered intensities is obtained numerically as a function of the phase difference between the beams for the case m = 2. Results are compared with the work of earlier investigators.

Plane‐wave multiple‐scattering approach to acousto‐optic diffraction by adjacent ultrasonics

Plane‐wave multiple‐scattering theory has been used to analyze the diffraction of light by adjacent ultrasonic beams of frequency ratio 1:m. The novelty of the method lies in the fact that it provides a better physical insight into the actual coupling process involved in the generation of various diffracted orders than earlier, more conventional analtyical techniques; hence the resulting equations may be arrived at by simply inspecting the geometry of the problem and incorporating the appropriate phase factors contributing to each order. The analyses of acousto‐optic diffraction by adjacent ultrasonic beams of frequency ratio 1:2 in the Raman‐Nath and near Raman‐Nath regimes are presented as illustrative examples. To compare with the work of earlier investigators, the variations of the scattered intensities are obtained numerically, for equal sound pressures in both columns, as a function of the phase difference between the beams and the strength of the sound fields for the first and second cases, respect...

Chronic pain: replicated multivariate clustering of personality profiles.

Cluster analyzed the MMPI profiles of 70 male chronic pain patients into four homogeneous subgroups. Mean composites for each subgrouping were entered into a PDP 11 computer to generate an objective actuarial narrative description. Findings appeared to extend and replicate the work of earlier investigators.

Biologic concomitants of alcoholism. 1.

"THE sway of alcohol over mankind," according to William James, "is unquestionably due to its power to stimulate the mystical facilities of human nature."2 But mystical sway represents only one portion of a continuum that may extend to severe biologic and social impairment for certain unfortunate victims. The scientific study of these heterogeneous persons, designated as "alcoholics," is a relatively new undertaking in biomedical science. Until recently, most alcohol-related problems were perceived as a moral issue, and alcoholism was not regarded as an appropriate subject for either laboratory or clinical investigation.Yet, in a curious way, the early investigative work . . .

Changes Associated with Parasitism in Nematodes. IV. Cytochemical Studies on the Ampulla of the Dorsal Esophageal Gland of Meloidogyne javanica and on Exudations from the Buccal Stylet

The ampulla of the dorsal esophageal gland and exudations from the buccal stylet were examined in both living and fixed nematodes by various cytological techniques. A pronounced ampulla is found only in females. It is packed with granules which are approximately 0.4 to 0.6 u in diameter. By means of histochemical tests and examination with a UV microspectrograph they have been shown to consist predominantly of protein. Living females, when dissected from roots and placed in distilled water, produce a stylet exudate within a few hours. The use of a perfusion slide enabled this precipitate to be tested with various chemical reagents including stains and enzymes and it was shown to consist of basic proteins containing carbohydrates. Neither lipids, nucleic acids nor enzymes were detected. The possible role of these basic proteins in the host-parasite relationship is discussed. Previous papers in this series (Bird, 1967; Bird and Saurer, 1967; Bird, 1968) have been concerned with changes taking place in the subventral esophageal glands during the initial stages of parasitic development. No changes were detected in the dorsal esophageal gland or its ampulla near the base of the spear during this transition. It is clear, however, from the work of earlier investigators (Linford, 1937; Rhoades and Linford, 1961; Hechler, 1962; Anderson, 1964; Doncaster, 1966; and Nickle, 1967) that the ampulla of the dorsal esophageal gland is not only closely associated with feeding in stylet bearing nematodes but that its granular contents appear to be morphologically similar among widely divergent genera. As yet there is little information on the chemical nature of either the material in the ampulla or the oral precipitate which exudes from the stylets of plant parasitic nematodes. However, in Meloidogyne javanica, Bird (1964) has shown that these oral exudates are antigenic and are thought to consist of a number of proteins. Further information on the chemical nature of these structures is required if their role in the establishment, development and maintenance of the tumorlike giant cells on which these nematodes feed (Bird, 1961; 1962) is to be understood. In this paper the chemical compositions of the contents of the ampulla of the dorsal esophReceived for publication 14 May 1968. ageal gland and the stylet exudate are examined by various techniques in an effort to clarify at least some aspects of M. javanica's complex host-parasite relationship. MATERIALS AND METHODS Preparasitic and parasitic larvae were obtained by methods described previously (Bird, 1967). Females were dissected from galls in tomato roots using a stereo microscope and males were collected in tubes by sedimentation after they had migrated from tomato roots in a thermally controlled mist chamber. Living larvae and males were photographed at high resolution under anesthetic (Bird 1967). However, living females were not anesthetized because of their relative immobility but were examined with the coverslip raised slightly by means of a fine brass ring to prevent crushing. All specimens were photographed with the aid of electronic flash using either oil or water immersion objectives with normal transmitted light optics or phase contrast. Observations on both the material exuded from the tip of the buccal stylet in living females and the influence of various chemicals on these precipitates were made possible by the use of a perfusion chamber (Paul, 1957) and phase contrast optics incorporating a long-focal-length condenser. Pepsin (Calbiochem) was made up as a 0.1% solution in 0.1 N hydrochloric acid, trypsin (both BDH and Mann Research Labs) as a 0.1% solution in phosphate buffer (both pH 7.3 and 8.0) and papain (Calbiochem) as a 0.1% solution in phosphate buffer (pH 6.0). After fixation in 4% buffered formaldehyde (Bird and Saurer, 1967) both larvae and adults were examined and photographed under a Leitz microspectrograph, the spectra being recorded and scanned as previously described (Bird and Saurer, 1967).

Imipramine hydrochloride intoxication.

IMIPRAMINE HYDROCHLORIDE (Tofrānil) is a dibenzazepine closely related to chlorpromazine in its chemical structure, but having a quite different pharmacologie action. Imipramine was found to have a specific effect in dispelling depression. In 1957 Kuhn published the first paper on the treatment of depressive states with imipramine. Its exact mode of action is as yet not clearly defined. Its most useful action has been in periodic endogenous depressive states, in which it often eliminates the need for electroconvulsive therapy or markedly reduces the number of shock treatments needed. The recommended adult dosage is 75 to 100 mg. daily in divided amounts. This may be increased according to response and tolerance, but generally it is not necessary to exceed 200 mg. daily. In the early investigative work, side effects described were: sweating, dryness of the mouth, giddiness, tachycardia, constipation, urinary frequency or retention, disturbances of accommodation, fine and coarse tremors, and