bluuebunny/crossref_metadata_2025 huggingface dataset:
Dynamic acclimation to sunlight in an alpine plant, Soldanella alpina L.
Authors: Talhouët Anne‐Claire , Meyer Sylvie , Baudin Xavier , Streb Peter
Published: May 2019

In the French Alps, Soldanella alpina (S. alpina) grow under shade and sun conditions during the vegetation period. This species was investigated as a model for the dynamic acclimation of shade leaves to the sun under natural alpine conditions, in terms of photosynthesis and leaf anatomy. Photosynthetic activity in sun leaves was only slightly higher than in shade leaves. The leaf thickness, the stomatal density and the epidermal flavonoid content were markedly higher, and the chlorophyll/flavonoid ratio was significantly lower in sun than in shade leaves. Sun leaves also had a more oxidised plastoquinone pool, their PSII efficiency in light was higher and their non‐photochemical quenching (NPQ) capacity was higher than that of shade leaves. Shade‐sun transferred leaves increased their leaf thickness, stomatal density and epidermal flavonoid content, while their photosynthetic activity and chlorophyll/flavonoid ratio declined compared to shade leaves. Parameters indicating protection against high light and oxidative stress, such as NPQ and ascorbate peroxidase, increased in shade‐sun transferred leaves and leaf mortality increased. We conclude that the dynamic acclimation of S. alpina leaves to high light under alpine conditions mainly concerns anatomical features and epidermal flavonoid acclimation, as well as an increase in antioxidative protection. However, this increase is not large enough to prevent damage under stress conditions and to replace damaged leaves.
Oral lichen planus: A disease or a spectrum of tissue reactions? Types, causes, diagnostic algorhythms, prognosis, management strategies
Authors: Carrozzo Marco , Porter Stephen , Mercadante Valeria , Fedele Stefano
Published: May 2019

Oral lichen planus and lichenoid lesions comprise a group of disorders of the oral mucosa that likely represent a common reaction pattern to 1 or more unknown antigens. The coexistence of hyperkeratotic striation/reticulation, varying degrees of mucosal inflammation from mild erythema to severe widespread ulceration, and a band‐like infiltrate of mononuclear inflammatory cells including activated T lymphocytes, macrophages, and dendritic cells, are considered suggestive of oral lichen planus and lichenoid lesions. Several classification systems of oral lichen planus and lichenoid lesions have been attempted, although none seem to be comprehensive. In this paper, we present a classification of oral lichen planus and lichenoid lesions that includes oral lichen planus, oral lichenoid contact lesions, oral lichenoid drug reactions, oral lichenoid lesions of graft vs. host disease, discoid lupus erythematosus, and systemic lupus erythematosus, lichen planus‐like variant of paraneoplastic pemphigus/paraneoplastic autoimmune multiorgan syndrome, chronic ulcerative stomatitis, lichen planus pemphigoides, solitary fixed drug eruptions, and lichen sclerosus. We present the clinical and diagnostic aspects of oral lichen planus and lichenoid lesions, and discuss related treatment options.
Oral autoimmune vesicobullous diseases: Classification, clinical presentations, molecular mechanisms, diagnostic algorithms, and management
Authors: Leuci Stefania , Ruoppo Elvira , Adamo Daniela , Calabria Elena , Mignogna Michele Davide
Published: May 2019

Mucocutaneous blistering autoimmune diseases are a group of systemic, rare, chronic disorders characterized by humoral‐mediated immunologic mechanisms against epithelial, basement membrane, and subepithelial tissues. Morbidity and mortality can be completely different among these diseases, with outcome being dependent on an early and accurate diagnosis, systemic comorbidities, and the patient's response to treatment. Definitive diagnosis is based on clinical and histopathologic findings. Because clinical presentations among these diseases are often similar, different immunofluorescence tests and ELISAs are used to confirm the specific diagnosis. Oral mucosa may often be the first site of clinical manifestation from which the disease spreads to other mucosal surfaces and skin. Thus, often dentists and oral medicine specialists may be the first to encounter patients with such diseases. In this review we discuss the most frequent autoimmune vesicobullous disorders, namely pemphigus vulgaris, mucous membrane pemphigoid, bullous pemphigoid, and linear IgA disease.
Deserving to Whom? Investigating Heterogeneity in the Impact of Social Constructions of Target Populations on Support for Affirmative Action
Authors: Bell Elizabeth
Published: May 2019

The social construction of target populations has emerged as an influential framework for understanding the public policy process. In particular, target populations have been shown to shape the allocation of benefits and burdens by political elites. However, existing studies focus on the elite level, which overlooks whether public preferences are aligned with the allocation of policy benefits and burdens by political elites. Moreover, many studies treat social constructions as homogenous, which this paper calls into question. Using a nation‐wide survey experiment, I investigate variation in public support for affirmative action policies with randomly assigned target populations. The findings indicate that the public formulates policy preferences on the basis of perceived deservingness of target groups similar to political elites. In addition, the findings uncover heterogeneity in the effect of targeting on public opinion based on ideology and racial/ethnic group identity.
Successful information exchange between restoration science and practice
Authors: Clark Lisa B. , Henry Annie L. , Lave Rebecca , Sayre Nathan F. , González Eduardo , Sher Anna A.
Published: May 2019

The science‐practice gap is often cited as a limitation to successful restoration outcomes; however, the existence of such a gap in information exchange is rarely measured. Here, we quantify the gap by focusing on common recommendations from both scientists (i.e. researchers) and managers (i.e. practitioners, land managers) on what is needed for successful restoration. We surveyed 45 managers associated with 244 invasive species (Tamarix spp.) removal projects across the southwestern U.S. to determine the degree to which they have utilized four strategies advocated by scientists: (1) collaborate widely, (2) monitor beyond cursory visual methods, (3) use a variety of information sources, and (4) consider project goals beyond invasive species removal. Half of these managers were also interviewed to assess managers' perceptions of the role of science in restoration. Twenty‐three scientists specializing in Tamarix‐related research in this region were also surveyed to assess how much they understood and/or shared the concerns of land managers. We found that managers were following scientists' recommendations and that managers' perceptions of the role of science in land management did not have any bearing on the management actions taken. Scientists reported being influenced by managers, and the concerns of scientists and managers were more overlapping than expected. Boundary organizations and river‐wide partnerships were often cited as important in facilitating effective communication between land managers and scientists. A lack of funding for monitoring and for longer‐term projects was cited by both groups as a limitation to incorporating scientists' recommendations into restoration.
On the phylogenetic position and systematics of extant and fossil Aclopinae (Coleoptera: Scarabaeidae)
Authors: Neita‐Moreno Jhon César , Agrain Federico A. , Eberle Jonas , Ahrens Dirk , Pereyra Vanina
Published: May 2019

The Aclopinae is a small subfamily within the family Scarabaeidae. It currently comprises five extant genera with 28 species, and eight fossil genera with 25 species. The systematic position of Aclopinae within the family Scarabaeidae is uncertain, particularly because representative species of Aclopinae have been absent in previous phylogenetic studies. Here we performed phylogenetic analyses using morphological and molecular data to investigate the phylogenetic position of fossil and extant Aclopinae. For this objective, we expanded and revised a former morphological data matrix (composed of 68 characters) including all extant genera of Aclopinae. We complemented our morphological investigations with a molecular phylogenetic analysis based on four genes of several extant taxa of Aclopinae and a wide sample of diverse Scarabaeoidea. Our phylogenetic analyses show that all the type species of the fossil genera formerly included within Aclopinae do not belong within the extant Aclopinae clade and support both the exclusion of those fossil taxa and the monophyly of the extant genera of Aclopinae: Aclopus Erichson, Desertaclopus Ocampo & Mondaca, Gracilaclopus Ocampo & Mondaca, Neophanaeognatha Allsopp and Phanaeognatha Hope. Our results also show that the fossil taxa Prophaenognatha robusta Bai et al. and Ceafornotensis archratiras Woolley are closely related to Ochodaeidae, while the remaining type species of fossils formerly included in Aclopinae (Cretaclopus longipes (Ponomarenko), Holcorobeus vittatus Nikritin, Juraclopus rodhendorfi Nikolajev, Mesaclopus mongolicus (Nikolajev), and Mongolrobeus zherikhini Nikolajev) belong to a distinct lineage closely related to Diphyllostomatidae. Based on these results, the subfamily Aclopinae appears monophyletic and sister to the ‘pleurostict’ lineage. Consequently, we propose the following changes to the current classification of the fossil taxa: Holcorobeus monreali (Gómez‐Pallerola) belongs to Carabidae (incertae sedis) as proposed by the original author, and we place Ceafornotensis Woolley, Cretaclopus Nikolajev, Holcorobeus Nikritin, Juraclopus Nikolajev, Mesaclopus Nikolajev, Mongolrobeus Nikolajev and Prophaenognatha Bai et al. in Scarabaeoidea (incertae sedis). Furthermore, we provide an identification key to, and diagnoses of, the genera, illustrations of diagnostic characters and checklists of their included species. The evolutionary perspective presented provides new insights into the evolution of the pleurostict condition in Scarabaeoidea and the biogeography of this group, which is now regarded as Gondwanan, probably evolving during the Cretaceous and not from the upper Jurassic as previously assumed.
Photography and the Unseen
Authors: Lynteris Christos , Stasch Rupert
Published: May 2019

Drawing on works such as Shawn Michelle Smith’sAt the Edge of Sight(2013), we explore the idea that photography, in supporting new kinds of seeing, even more importantly provokes expanded cultural concern with that which is unseen. We explore different social, ideological, and epistemological presences beyond sight dealt with in Smith’s work on U.S. photographers, and in the ethnographic studies gathered in this themed section. The four articles together underline the historical variability of the specific kinds of unseen that inform photographs’ visible content and are created through it.
“Our Ancient Monuments”: Visualizing Documents in Stone
Authors: Edwards Elizabeth
Published: May 2019

This article explores the ways in which, during the interwar period, practices of state preservation of ancient monuments in Britain established a visual rhetoric of “monument as document.” This was expressed through photographic postcards and the visual presentation of monuments themselves. Informed by an entangled ethos of scientific archaeological understanding, public education, and discourses of public ownership, I argue that photographs established and projected patterns of visibility and legibility, which addressed these core values of preservation, educative interpretation, and public access, within the practices of the “techno‐state.”
LAME SCIENCE? BLIND RELIGION?
Authors: Rolston Holmes
Published: May 2019

In Consecrating Science, Lisa Sideris argues that an anthropocentric and science‐based cosmology encourages human arrogance and diminishes a sense of wonder in human experience immersed in the natural world, as found in diverse cultural and religious traditions. I agree with her that science elevated to a commanding worldview, scientism, is a common and contemporary mistake, to be deplored, a lame science. But I further argue that science has introduced us to the marvels of deep nature and vastly increased our human appreciation of nature as a wonderland at levels great and small. Sideris is right to fear consecrating science. She—and the humanists, sages, and saviors—need also to fear blindness to what science has to teach us about cosmogenesis and wonderland Earth.
REVEREND ROBOT: AUTOMATION AND CLERGY
Authors: Young William
Published: May 2019

Digital technology, including artificial intelligence, is having a dramatic impact on the professions of medicine, law, journalism, finance, and others. Some suggest that clergy will also be affected. We describe recent progress in designing artificially intelligent systems, suggesting that this is possible, perhaps even likely. We investigate ways in which technology currently is affecting ministry and outline some plausible scenarios in which digital systems could supplement or supplant clergy in some areas, specifically preaching and pastoral care. We also raise some theological issues raised by the use of digital systems in ministry.
JOURNEY OF THE UNIVERSE: WEAVING SCIENCE WITH THE HUMANITIES
Authors: Tucker Mary Evelyn
Published: May 2019

This article discusses Journey of the Universe as a project that consists of a film, book, conversation series, online classes, and a website. It describes how the creators worked to integrate science and humanities, not privilege or elevate science. It refutes arguments made in Lisa Sideris's Consecrating Science: Wonder, Knowledge, and the Natural World that suggest that Journey overlooks religion and distorts wonder. The article observes that Journey does not dismiss religion but includes it in explicit ways. It does not dictate wonder; it evokes wonder. In short, Journey is a living or functional cosmology with implications for mutually enhancing human–Earth relations.
AUGMENTED REALITY, ARTIFICIAL INTELLIGENCE, AND THE RE‐ENCHANTMENT OF THE WORLD
Authors: Chaudhary Mohammad Yaqub
Published: May 2019

There has recently been a surge of development in augmented reality (AR) technologies that has led to an ecosystem of hardware and software for AR, including tools for artists and designers to accelerate the design of AR content and experiences without requiring complex programming. AR is viewed as a key “disruptive technology” and future display technologies (such as digital eyewear) will provide seamless continuity between reality and the digitally augmented. This article will argue that the technologization of human perception and experience of reality, coupled with the development of artificial intelligence (AI)–based natural language assistants, may lead to a secular re‐enchantment of the world, in the sense outlined by Charles Taylor, where human existence is shaped through AR inhabited by advanced personal and social AI agents in the form of digital avatars and daemons, and that enchantment has been persistent throughout the formation of modernity and is being rekindled by the integration of AI in the plane of AR.
Responses of cerebral blood velocity and tissue oxygenation to low‐frequency oscillations during simulated haemorrhagic stress in humans
Authors: Anderson Garen K. , Sprick Justin D. , Park Flora S. , Rosenberg Alexander J. , Rickards Caroline A.
Published: May 2019

New Findings

What is the central question of this study?

Do low‐frequency oscillations in arterial pressure and cerebral blood velocity protect cerebral blood velocity and oxygenation during central hypovolaemia?

What is the main finding and its importance?

Low‐frequency oscillations in arterial pressure and cerebral blood velocity attenuate reductions in cerebral oxygen saturation but do not protect absolute cerebral blood velocity during central hypovolaemia. This finding indicates the potential importance of haemodynamic oscillations in maintaining cerebral oxygenation and therefore viability of tissues during challenges to cerebral blood flow and oxygen delivery.

Tolerance to both real and simulated haemorrhage varies between individuals. Exaggerated low‐frequency (∼0.1 Hz) oscillations in mean arterial pressure and brain blood flow [indexed via middle cerebral artery velocity (MCAv)] have been associated with improved tolerance to reduced central blood volume. The mechanism for this association has not been explored. We hypothesized that inducing low‐frequency oscillations in arterial pressure and cerebral blood velocity would attenuate reductions in cerebral blood velocity and oxygenation during simulated haemorrhage. Fourteen subjects (11 men and three women) were exposed to oscillatory (0.1 and 0.05 Hz) and non‐oscillatory (0 Hz) lower‐body negative pressure profiles with an average chamber pressure of −60 mmHg (randomized and counterbalanced order). Measurements included arterial pressure and stroke volume via finger photoplethysmography, MCAv via transcranial Doppler ultrasound, and cerebral oxygenation of the frontal lobe via near‐infrared spectroscopy. Tolerance was higher during the two oscillatory profiles compared with the 0 Hz profile (0.05 Hz, P = 0.04; 0.1 Hz, P = 0.09), accompanied by attenuated reductions in stroke volume (P < 0.001) and cerebral oxygenation of the frontal lobe (P ≤ 0.02). No differences were observed between profiles for reductions in mean arterial pressure (P = 0.17) and MCAv (P = 0.30). In partial support of our hypothesis, cerebral oxygenation, but not cerebral blood velocity, was protected during the oscillatory profiles. Interestingly, more subjects tolerated the oscillatory profiles compared with the static 0 Hz profile, despite similar arterial pressure responses. These findings emphasize the potential importance of haemodynamic oscillations in maintaining perfusion and oxygenation of cerebral tissues during haemorrhagic stress.
A novel textile wastewater treatment using ligninolytic co-culture and photocatalysis with TiO2
Authors: Blanco-Vargas Andrea , Ramírez-Sierra Christian Fernando , Duarte Castañeda Marcela , Beltrán-Villarraga Milena , Medina-Córdoba Luz Karime , Florido-Cuellar Alex Enrique , Cardona-Bedoya Jairo Armando , Campos-Pinilla María Claudia , Pedroza-Rodriguez Aura Marina
Published: May 2019

Textile industries produce effluent waste water that, if discharged, exerts a negative impact on the environment. Thus, it is necessary to design and implement novel waste water treatment solutions. A sequential treatment consisting of ligninolytic co-culture with the fungi Pleurotus ostreatus and Phanerochaete crhysosporium (secondary treatment) coupled to TiO2/UV photocatalysis (tertiary treatment) was evaluated in the laboratory in order to discolor, detoxify, and reuse textile effluent waste water in subsequent textile dyeing cycles. After 48 h of secondary treatment, upto 80 % of the color in the waste water was removed and its chemical and biochemical oxygen demands (COD, and BOD5) were abated in 92 % and 76 %, respectively. Laccase and MnP activities were central to color removal and COD and BOD5 abatement, exhibiting activity values of 410 U.L-1 and 1 428 U.L-1, respectively. Subjecting waste water samples to 12h of tertiary treatment led to an 86 % color removal and 73 % and 86 % COD and BOD5 abatement, respectively. The application of  a sequential treatment for 18 h improved the effectiveness of the waste water treatment, resultingin 89 % of color removal, along with 81 % and 89 % COD and BOD5 abatement, respectively. With this sequential treatment a bacterial inactivation of 55 % was observed. TiO2 films were reused continuously during two consecutive treatment cycles without thermic reactivation. Removal percentages greater than 50 % were attained. Acute toxicity tests performed with untreated waste water led to a lethality level of 100 % at 50 % in Hydra attenuata and to a growth inhibition of 54 % at 50 % in Lactuca sativa. Whereas sequentially treated waste water excreted a 13 % lethality at 6.25 % and aninhibition of 12 % at 75 % for H. attenuata and L. sativa, respectively. Finally, sequentially treated waste water was reused on dyeing experiments in which 0.86 mg.g-1 adsorbed dye per g of fabric, that is equivalent to 80 % of dye adsorption.
Soil macrofauna in areas with different ages after Pinus patula clearcutting
Authors: Tulande-M Esteban , Barrera-Cataño Jose Ignacio , Alonso-Malaver Carlos Eduardo , Basto Sofia
Published: May 2019

In Andean high montane areas, the establishment of exotic tree forests changes the soil dynamics and its biodiversity. Soil macrofauna act as indicators of ecosystem successional processes, and may have an important role in ecological restoration processes after clear cutting exotic tree plantations. The aim of the present study was to understand how soil macrofaunal assemblies change in areas with different ages post clear cutting of Pinus patula, and to identify the soil physico-chemical variables that better explain these variations. The macrofauna in a high montane forest was evaluated along with that of three areas with different ages post clearcutting: 0, 2.5, and 5 years after clearcutting (Yac). The effect of soil physico chemical variables on macrofauna abundance was also evaluated. Macrofauna composition changed after clearcutting. Macrofauna abundance, richness, and diversity were lower in the 0 Yac area than in the other areas. Moreover, the macrofuna similarity to the reference forest did not increase with the years after clearcutting. This is due to the changes in soil characteristics, triggered by clearcutting. Slope, temperature, bulk density, real density, loam, pH, P, Na and K were the soil variales with a positive effect on the macrofauna abundance. These physico-chemical variables should be considered when designing restoration plans for Andean forest ecosystems. Moreover, Diplopoda, Coleoptera and Chilopoda might be useful to monitor and evaluate restoration processes after Pinus spp. clearcutting, because of their high abundance, diversity and relationship with environmental conditions.
Some Thoughts About the Development of Automotive Gas-Turbine Units
Authors: Bowden A. T. , Hryniszak W.
Published: May 2019

Possible configurations for an automotive gas-turbine unit are considered. Comparisons are made of designs taking the drive from the high-pressure and low-pressure portions of a split turbine, as well as the advantages to be gained with a divided-compressor and differential-gear arrangement.
M-252 Alloy for Heavy-Duty Gas-Turbine Buckets
Authors: Fusner G. R. , Newhouse D. L.
Published: May 2019

In order to apply safely a turbine-bucket alloy which has been successful in short-life high-temperature aircraft gas turbines to long-life heavy-duty gas turbines, it was necessary to make many laboratory tests. These included tensile, rupture, creep, fatigue, damping, oxidation, and corrosion tests. Many of these tests were made on specimens which had been aged for 5000 and 10,000 hr. Rupture data were obtained to 15,000 hr. Operating experience has confirmed laboratory tests and now M-252 is destined to become a standard bucket material for heavy-duty gas turbines.
Load Capacity Tests on Tapered-Land and Pivoted-Shoe Thrust Bearings for Large Steam-Turbine Application
Authors: Brandon R. E. , Bahr H. C.
Published: May 2019

Results of full-scale maximum load capacity tests on large, 3600-rpm, pivoted-shoe and tapered-land thrust bearings are reported. The results show 700 psi capacity for the pivoted-shoe bearing and 1085 psi for the tapered-land type. Additional evidence of thermal distortion and its effect on thrust-bearing capacity are discussed. A brief description of a new thrust-bearing test installation also is included.
Rocket Turbines
Authors: Lancaster Otis E. , Bates Carlton J.
Published: May 2019

Rocket turbines have come into prominence in the last 20 years chiefly as sources of power for rocket pumps and auxiliary missile requirements. Most are of an impulse type with low efficiencies yet very low weights. Varying from 2 to 20 in. in diam with powers from 1 to 15,000 hp, they are designed to operate for durations of 1 to 5 min with total life of 1 to 50 hr. Although rotational speeds are as high as 100,000 rpm, the tip Mach numbers are lower than in conventional turbojet blades.
Marine
Authors: Sawyer John W. , Simpson Harry M.
Published: May 2019

This is a progress report on the marine gas turbine and free-piston gas turbine during the 5-yr period, 1953–1957. Since the merchant and naval services encompass many similar operating conditions—in spite of many differing requirements—the entire marine field will be reviewed in a single paper. In the first report [18], separate papers appeared on marine, merchant, and naval applications.

Open and closed-cycle gas-turbine, nuclear gas-turbine, and free-piston gas-turbine prime movers will be discussed along the following lines: Applications, operating experience, development, advantages, disadvantages, economics, and the future potential in the marine field.
The Effect of Fuel Types and Admission Method Upon Combustion Efficiency
Authors: McManus H. N. , Ibele W. E. , Murphy T. E.
Published: May 2019

A series of tests to determine the effect of combustion-chamber length for three different types of fuel admission (gaseous, spray, and vaporized) upon combustion efficiency was performed in identical combustor geometries and with similar air-flow patterns. The effects of fuel-air ratio and full-section velocity were examined for individual methods of admission. The effect of fuel volatility also was examined. It was found that the vaporized fuel type of admission was superior in efficiency to the spray-fuel admission in all comparable cases. Increased fuel volatility improved performance in the case of the vaporizer but did not affect the performance of the spray nozzle. The performance of vaporising tubes was found to vary inversely with size. An optimum size was exhibited.
Heat Transfer to a Boiling Liquid—Mechanism and Correlations
Authors: Engelberg-Forster Kurt , Greif R.
Published: May 2019

Various heat-transfer mechanisms which have been previously proposed are analyzed in the light of recent experiments. Evidence is presented in favor of a vapor-liquid exchange mechanism. The vapor-liquid exchange mechanism is shown to explain the insensitivity of boiling heat flux to the level of subcooling. A “Reynolds’ analogy” for nucleate boiling is presented in some detail. A procedure is given for calculating the superheat at which the liquid bulk velocity ceases to contribute to the heat flux. An expression for the growth of a vapor bubble in a highly superheated liquid is deduced. A method is presented which allows the deduction of correlations for nucleate boiling which give the dependence of heat flux on superheat and system pressure. Two such correlations are presented and results are compared with experiment. It is shown that one correlation yields the heat flux for different liquids varying from water to mercury, without necessitating any change in constant or exponent of the correlation.
A Theory of Rotating Condensation
Authors: Sparrow E. M. , Gregg J. L.
Published: May 2019

An analysis is made for film condensation on a rotating disk situated in a large body of pure saturated vapor. The centrifugal field associated with the rotation sweeps the condensate outward along the disk surface, and gravity forces need not be involved. The problem is formulated as an exact solution of the complete Navier-Stokes and energy equations. Numerical solutions are obtained for Prandtl numbers between 0.003 and 100 and for cpΔT/hfg in the range 0.0001 to 1.0. Results are given for the heat transfer, as well as for the condensate layer thickness, torque moment, and temperature and velocity profiles.
Heat Transfer to Water in Thin Rectangular Channels
Authors: Levy S. , Fuller R. A. , Niemi R. O.
Published: May 2019

Heat-transfer coefficients are presented for water flowing vertically in thin rectangular channels (0.1 × 2.5 in.) 18 and 36 in. long and heated electrically around the entire periphery. The range of variables covered is: 65 to 200 psia pressure, 90 to 200 F sub-cooling, and 4 to 50 fps water velocity. Heat-transfer correlations are given for data along the narrow and wide faces of the rectangular test section. Burnout data also are reported with steam blanketing occurring first at the corner of the test section. The proposed correlating equation, valid at the narrow face of the test section, gives values considerably lower than those obtained in a circular pipe.
An Experimental and Analytical Study of Vortex-Flow Temperature Separation by Superposition of Spiral and Axial Flow: Part 2
Authors: Lay J. E.
Published: May 2019

Part 2 reports on the analytical study. The free vortex motion of the gas upon entrance to the tube is mathematically superposed to a compressible sink to give a spiral flow in the plane. The characteristic existence of limit circles is corroborated by the experimental flow visualization. The solution in space is obtained by addition of a uniform axial velocity to the spiral flow. When viscosity effects are considered, the free vortex is shown to change into a forced vortex. The latter flow is one of minimum kinetic energy and maximum entropy. Energy considerations enable the determination of an optimum cold air radius to give largest stagnation temperature separation. Significantly, this was the radius that gave best performance in the experimental program.
Analysis of the Aerodynamic Heating for a Re-Entrant Space Vehicle
Authors: Brunner M. J.
Published: May 2019

An analysis of the aerodynamic heating is presented through the trajectory and over the surface of a re-entrant hypersonic space vehicle. Bodies exhibiting zero and high lift over drag ratios are considered. The turbulent and laminar convective heat inputs are specified as functions of the trajectory and space vehicle parameters. The maximum heating rates and time integrated heat fluxes are given as functions of the local pressure distribution, body geometry, and wall temperature. Examples are presented to illustrate the application of this analysis.
Some Radiator Design Criteria for Space Vehicles
Authors: Callinan Joseph P. , Berggren Willard P.
Published: May 2019

Nonconvective radiators of single or double-active surface design are analyzed for surface temperature distribution; also for view factors in the case of fin-and-tube geometry. Methods and examples of maximizing heat rejection per unit weight are given.
The Use of Thin Films for Increasing Evaporation and Condensation Rates in Process Equipment
Authors: Lustenader E. L. , Richter R. , Neugebauer F. J.
Published: May 2019

This paper describes an experimental investigation of an evaporating and condensing test apparatus in which over-all heat-transfer coefficients as high as 8000 Btu/(hr) (sq ft) (deg F) were obtained with water by utilizing thin films both in evaporation and condensation. The films were obtained by wiping on the evaporating surface and utilizing surface tension effects on the condensing surface. The phenomena on both the evaporating and the condensing surfaces are amenable to theory.
The Penetration of Planetary Atmospheres
Authors: Gazley Carl
Published: May 2019

The problems of penetrating a planetary atmosphere are reviewed and techniques for penetration are discussed. These techniques are resolved into two general classes: (1) Gradual entry into the atmosphere with relatively low deceleration loads and heating rates low enough so that the heat may be rejected by thermal radiation from the surface; and (2) direct entry with higher deceleration loads and higher heating rates with the heat being absorbed by the body surface.
Vibrations of Vertical Pressure Vessels
Authors: Freese C. E.
Published: May 2019

This paper is primarily concerned with the vibration of vertical pressure vessels known as columns or towers.

The procedure for estimating the period of the first mode of vibration for columns which are the same diameter and thickness for their entire length is outlined. A graph is included for this purpose which recommends limits between vessels considered to be static structures and those considered dynamic.

A method for designing vessels considered as dynamic structures is described as well as a detailed procedure for estimating the period of vibration of multithickness (stepped shell) vessels and/or vessels built to two or more diameters with conical transitions where the difference in diameter is small.

There is a brief résumé of the “Karman vortexes” effect and a discussion regarding vibration damping by liquid loading and the benefit of ladders and platforms which help reduce the effect of periodic eddy shedding.

The design procedure outlined will be useful to the practical vessel designer confronted with the task of investigating vibration possibilities in vertical pressure vessels.
A Study of the Effects of Tool Flank Wear on Tool Chip Interface Temperature
Authors: Olberts D. R.
Published: May 2019

A study of the effect of land wear upon the interface temperature between a carbide tool and an AISI 1015 steel workpiece is presented. The wear lands were ground on the tools to eliminate the effects of cratering and to produce uniform wear lands. The tool-work thermocouple technique was used to measure the interface temperature. A calibration of the thermocouple was obtained through the use of a technique suggested by Backer and Krabacher. The results at all feeds and speeds indicate that a wear land of 0.010 in. produces a lower interface temperature than a sharp tool. When the wear land increases beyond 0.010 in. to 0.020 and 0.030 in. the temperature again rises. Studies of the variation of the chip thickness ratio with wear land indicated that the greater the land wear the lower the chip thickness ratio.
Theory and Experiment of Press Forging Axisymmetric Parts of Aluminum and Lead
Authors: Kobayashi S. , Herzog R. , Lapsley J. T. , Thomsen E. G.
Published: May 2019

The mechanics of finishing in a press-forging operation were analyzed. It was concluded that the metal in the die, as well as that contained in the flash, could be treated as a fictitious disk which is subjected to compression between flat surfaces under variable surface friction. Comparison of experimental average pressures with those predicted by the foregoing simplified theory showed good agreement.
Four-Bar Linkages—Approximate Synthesis
Authors: Worthley W. W. , Hinkle R. T.
Published: May 2019

An analytical method for synthesizing a four-bar linkage as a function generator is presented. The method, which permits the arbitrary selection of four precision points and finite angular ranges, is based on a graphical solution. This permits a preliminary graphical investigation of the six possible linkages before selecting one for analytical treatment.
An Application of Statistics to the Dimensioning of Machine Parts
Authors: Spotts M. F.
Published: May 2019

An outstanding industrial achievement during recent years has been the development of quality control and acceptance sampling methods for the purpose of maintaining the high standards of manufactured products. It is equally important to make use of statistics in the engineering office in connection with the dimensioning of machine parts. This paper will be concerned with the dimensioning of assemblies, and will demonstrate how it is possible to maintain tolerances for proper engineering functioning, and at the same time widen the tolerances so far as production is concerned.
A Variational Approach to Lubrication Problems and the Solution of the Finite Journal Bearing
Authors: Hays D. F.
Published: May 2019

A general method is derived for the solution of the two-dimensional Reynolds’ equation. The method is applied to the solution of the full journal bearing of finite width with a continuous film and design charts are presented which describe the characteristics of this bearing.
Analysis and Characteristics of the Three-Lobe Bearing
Authors: Pinkus O.
Published: May 2019

An analytical solution of 3-lobe journal bearings is offered based on the solution of the finite Reynolds equation. Expressions for eccentricity, lubricant flow, power loss, and spring constant are given for a range of L/D ratios and ellipticities. The bearing is shown to be of superior quality both in its stability characteristics and in its hydrodynamic performance. Charts and equations for setting design requirements and calculating performance are given in simple convenient form.
Sliding Wear and Metal Transfer Under Unlubricated Conditions
Authors: Steijn R. P.
Published: May 2019

To provide further information on dry sliding wear and the accompanying metal transfer, wear experiments of radioactive brass rings against hardened steel have been conducted in a ring tester. The effect on metal transfer of sliding speed, surface finish, material of the harder surface, and the presence of slots in the steel ring have been investigated. Tests have also been conducted in argon atmospheres to exclude oxidation.

Wear of brass on brass has been investigated by using radioactive rings against inactive rings. Results indicate a complex wear mechanism in which transfer, back transfer, and removal of transferred material are intermediate steps, and in which the determining step in wear rate is governed by the geometry of the rings rather than the apparent area of contact.
Cavitation and NPSH Requirements of Various Liquids
Authors: Salemann Victor
Published: May 2019

Test results on the net positive suction head, NPSH, requirements for centrifugal pumps handling water up to 420 F, some hydrocarbons, and Freon-11 are presented. Satisfactory pump performance was observed with net positive suction heads less than those required by the pump on cold water. A direct measurement of NPSH was attempted and is reported. The cavitation process is discussed and a correlation and method of prediction for all liquids is proposed.
Irradiation of Haynes-25 and Inconel-X Compression Springs in High-Temperature High-Pressure Water
Authors: Mehan R. L.
Published: May 2019

Irradiation tests were performed on Haynes Stellite Alloy 25 and Inconel-X springs irradiated in the compressed condition in an in-pile high-temperature water loop. The loop was operated at 560 to 600 F and the springs of both materials received integrated fluxes of 5.9 × 1018 and 4.2 × 1019 nvt fast, respectively. Postirradiation testing and examination revealed no serious deleterious effects resulting from these exposures. It was found the spring constant increased 5 to 8 per cent after exposure and the free length decreased 2 to 3 per cent. The effect of irradiation on the plastic-flow curve was slight as revealed by three-point loaded bend tests on 0.160-in-diam rods irradiated with the springs.
Surface Finish and Clearance Effects on Journal-Bearing Load Capacity and Friction
Authors: Ocvirk F. W. , DuBois G. B.
Published: May 2019

A method of relating surface finish to minimum oil-film thickness and the corresponding load capacity of plain journal bearings is presented with supporting experimental data. The effect of clearance on load capacity and friction are shown on graphs indicating an optimum bearing clearance.
Some Measurements of Boundary-Layer Growth in a Two-Dimensional Diffuser
Authors: Norbury J. F.
Published: May 2019

Low-speed experiments were carried out in a two-dimensional diffuser having a square throat and an area ratio of two to one. Measurements were made of static pressure distribution, velocity contours at throat and outlet, and boundary-layer growth along the four wall center lines. Visual flow experiments were performed using tufts and smoke filaments. Similar experiments were carried out with the throat boundary layers artificially thickened by means of round rods placed on the walls upstream. Disparities between the measured growth of momentum thickness and that predicted by the simple momentum equation are discussed, as well as the effect of the artificial thickening on diffuser efficiency.
Deriaz Type Reversible Pump-Turbine Installation at Sir Adam Beck-Niagara Forebay Pumped Storage Project
Authors: Aeberli A. E.
Published: May 2019

This paper describes the new adjustable blade, single-speed, vertical, single-runner reversible pump-turbine units recently developed and placed into service at Ontario Hydro’s forebay storage pumping-generating station at the S.A.B. Power Project on the Niagara River.

The units operate under unusual variations in head. In the pumping sequence the limits are 59 and 90 ft and in the turbine cycle from 45 to 85 ft. Tailwater depression is not required on start-up. Change-over from turbine to pumping sequence is accomplished in a matter of minutes and occurs several times each day. Data are given on the performance requirements for capacity and efficiency versus hydraulic operating conditions of head, tail water, and forebay reservoir levels. Information in the paper includes unusual features of mechanical design.
Tests on Deflection of Flat Oval Bourdon Tubes
Authors: Kardos G.
Published: May 2019

To fill the gap in knowledge of Bourdon tube deflection data, the method and results of tests on 70 varied flat oval Bourdon tubes are given. The results are compared against published design data. The results are evaluated to determine the function of the deflection with respect to geometric parameters.
Performance Investigation of a Triangular Solar Air Heater Duct Having Broken Inclined Roughness Using Computational Fluid Dynamics
Authors: Jain Sheetal Kumar , Agrawal Ghanshyam Das , Misra Rohit , Verma Prateek , Rathore Sanjay , Jamuwa Doraj Kamal
Published: May 2019

Large-scale adaptation of solar air heating in industries and agro-processing will lead to clean energy processing as well as reducing the production cost for these industries. The solar air heater uses the principle of the greenhouse effect to heat air through the collected heat in the absorber. Among the various techniques employed by the researchers to augment heat transfer, the addition of artificial roughness elements/fins/corrugations on the heated surface is the promising one for heat transfer augmentation. In the present work, the effect of broken inclined ribs with rectangular cross-section on heat transfer and friction characteristics of the equilateral triangular passage duct has been analyzed using computational fluid dynamics. The effect of roughness parameters, viz., relative gap position and relative gap width, is being investigated for the Reynolds number (Re) ranging from 4000 to 18,000. The values of relative gap position (d/W) and relative gap width (g/e) are varied from 0.16 to 0.67 and 0.5 to 2, respectively, while a constant heat flux is supplied on the absorber side, other surfaces being insulated. The Nusselt number increased up to 2.16 times by using broken ribs than that of the smooth duct at d/W = 0.25 and g/e = 1.
Criteria for Eliminating Cyclic Limit for PVHO Flat Disc Windows
Authors: Kemper Bart
Published: May 2019

Acrylics (Poly Methyl Methalcrylate, or PMMA) are a proven, reliable material for Pressure Vessel for Human Occupancy (PVHO) windows. The current codes and standards reflect a first-generation development of defining a nonmetallic for pressure vessel application. Subsequent investigations in material science as well as decades of operational experience indicates the code-specified 10,000 cycle limit for some flat disc acrylic ASME PVHO windows may be eliminated using criteria consistent with the ASME Boiler and Pressure Vessel Code

Paper published with permission.
Inservice Examination and Testing Issues for Dynamic Restraints (Snubbers) in Nuclear Power Plants
Authors: Bedi Gurjendra S.
Published: May 2019

This paper discusses recent issues related to inservice examination and testing of dynamic restraints (snubbers) at U.S. nuclear power plants. These issues were identified during the U.S. Nuclear Regulatory Commission (NRC) staff review of snubber examination and testing programs, relief requests, and applicable operating experience. This discussion includes information that could have generic applicability in the implementation of effective snubber programs at U.S. nuclear power plants.

Paper published with permission.
The MOV Issue: Perspective From Consejo de Seguridad Nuclear (C.S.N.) / Spain
Authors: Pérez Alfonso
Published: May 2019

The “Consejo de Seguridad Nuclear” (Nuclear Safety Council), or CSN, is the nuclear regulatory body of Spain.

U.S. Nuclear Regulatory Commission (NRC) regulations and standards have been primarily used in the past up to the present. However, there is a process such that regulations recently generated in Spain replace or complement regulations coming from other countries. This is not the case with the evaluation and control of motor-operated valves (MOVs), which are mainly monitored using the process described in Generic Letters 89-10 and 96-05.

During a nine-month assignment from April to December 1989 at NRC offices in King of Prussia, PA, the author gained knowledge of NRC Bulletin 85-03 and of Generic Letter 89-10, which was issued in June 1989. The author realized the importance of these communications for improving the safety of the plants in the future if the issues they describe are adequately managed and solved.

Paper published with permission.
Ultrasound findings of urachal anomalies. A series of interesting cases
Authors: Luo Xianghong , Lin Jun , Du Lianfang , Wu Rong , Li Zhaojun
Published: May 2019

Aims: This study’s aim is to present the specific ultrasonography (US) findings of a series of urachus anomalies. Material and methods: Seven patients with suspected urachal anomalies underwent US scanning initially prior to the surgery and the features of images were reviewed respectively. The clinical data and pathologic results were collected also. Results: US successfully diagnosed urachal anomalies in 5 patients (5/7, 71.4%) and failed to diagnose in 2 patients (2/7, 28.6%). Patent urachus showed a tubule between the umbilicus and bladder; urachal sinus was a blind focal dilatation at the umbilical end, while vesicourachal diverticulum was an outpouching at the vesical end and urachal cyst was identified as an anechoic structure along the urachus. Non-enhancement in the base and centre was the distinct features of urachus carcinoma by contrastenhanced ultrasonography (CEUS). Using a high frequency probe and CEUS the diagnostic ability of US may be improved. Conclusion: US showed good diagnostic ability in urachal anomalies and combined with CEUS could improve the differential diagnosis.
Asymmetry of Body Weight Distribution During Quiet and Relaxed Standing Tasks
Authors: Prado-Rico Janina M. , Duarte Marcos
Published: May 2019

The goal of this work was to investigate body weight distribution during relaxed and quiet (constrained) standing tasks. Forty-one healthy, young adults performed relaxed and quiet standing tasks, and they stood with each leg on a separate force plate. The weight distribution asymmetry across time was computed as the difference between the right and left vertical force time series. The subjects presented a small average across time asymmetry during relaxed and quiet standing. However, during relaxed standing, the subjects alternated between postures, and, as a result, they were largely asymmetrical over time (instant by instant). Two unexpected results that the authors found for the relaxed standing task were that women were more asymmetrical over time than men and that there were two preferential modes of weight distribution.
Global pattern of phytoplankton diversity driven by temperature and environmental variability
Authors: Righetti Damiano , Vogt Meike , Gruber Nicolas , Psomas Achilleas , Zimmermann Niklaus E.
Published: May 2019

In situ data and modeling offer a first global view of the spatial pattern of phytoplankton species richness in the ocean.