bluuebunny/crossref_metadata_2025 huggingface dataset:
Modern Hydraulic Turbines of Large Capacity
Authors: Acres H. G.
Published: January 2024

Modern super-turbine practice presents the problems of controlling high static pressures, of controlling and utilizing the flow characteristics in long pipe lines, and of controlling a highly energized water column and handling the heavy revolving weights of generator and turbine. The author outlines the general specifications for apparatus to accomplish these objects, and shows how the development of the Johnson automatic plunger valve, the Johnson differential surge tank, and the Kingsbury thrust bearing have successfully solved the problem and made the modern turbine possible. Other refinements in design which have had a notable influence on turbine development are improvements in turbine governors, experimental work on draft tubes, methods of preventing leakage, and the Taylor sectional scroll case. Pitting and corrosion of runners can now be avoided by the adoption of a conservative specific speed.

The improvement in efficiency of turbines is exemplified by the 55,000-hp. units of the Queenston plant of the Hydro-Electric Power Commission of Ontario. These have a maximum efficiency of 93.5 per cent, an efficiency at the point of maximum discharge of 88 per cent, and a capacity range of 37,000 to 60,000 hp. at efficiencies of 92 per cent or over.

New developments in test methods include the Gibson process of determining the rate of flow in long closed pressure conduits, and the Allen “salt velocity” method of determining flow, which is especially applicable to short conduits of non-uniform section. The Gibson method is more accurate and precise than the electrical measurements used in conjunction with it.
Boiler–Plant Economics
Authors: Funk N. E. , Ralston Farley C.
Published: January 2024

Noting the lack of adequate mathematical treatment in the literature on the subject, the authors have applied themselves to the determination of a rational formula for expressing boiler-plant performance. The paper shows how this formula may be applied, and also discusses the question of operating at minimum cost. The authors believe that with the analysis which they present considerably more rational practice can be followed, both in the matter of daily operation of existing boiler plants and in the design of new plants.
Performance of Centrifugal Fans for Electrical Machinery
Authors: Fechheimer Carl J.
Published: January 2024

The ordinary commercial centrifugal fan is provided with a stationary collecting device, generally a volute, which usually improves the performance materially. In the fans used for cooling electrical machinery, however, such collecting devices cannot be readily applied and the revolving impeller therefore forms the sole means for developing the pressure needed to drive the air through the vent ducts. The present paper gives results of an extended series of tests recently made to determine the performance of centrifugal fans without collecting devices, and to obtain sufficient data to enable designers to select types of fans intelligently and to predict their performance.
A Review of Steam-Turbine Development
Authors: Dahlstrand Hans
Published: January 2024

The paper is chiefly concerned with the effects which the use of steam at higher pressures and temperatures has had upon the efficiencies of steam turbines and upon the materials used in the construction of their parts. The use of high-back-pressure steam turbines, to be installed in connection with boilers of higher pressure in such a way as to exhaust into the steam mains and turbines of existing plants, is carefully analyzed for units of 10,000- and 30,000-kw. capacity, and the effects on the efficiency are graphically presented. A discussion of materials for use with the higher pressures and temperatures is included, with some curves showing the results of investigations made by the Allis-Chalmers Co. on various metals and the characteristics which should be possessed by a metal suitable for use at 1000 deg. fahr. The paper also contains some comments on corrosion and erosion of turbine blades, and shows the effects of these destructive forces on blades of different composition.
Analysis of Power-Plant Performance Based on the Second Law of Thermodynamics
Authors: DeBaufre Wm. L.
Published: January 2024

The author shows that the commonly used heat balance based on the first law of thermodynamics does not allocate the losses in a power plant in such a manner as to reveal the best points of attack on the problem of improving power-plant economy. The application of the second law gives a quite different statement of the losses of energy from the coal pile to the stack and engine exhaust. As an example, the performance of a locomotive is analyzed by both the first- and second-law methods.
Torsional-Stress Concentrations in Shafts of Circular Cross-Section and Variable Diameter
Authors: Jacobsen Lydik S.
Published: January 2024

The object of this paper is to point out an electrical experimental method for finding the torsional-stress distribution in cylindrical shafts of circular cross-section and of any axial outline. The method has been applied to the problem considered by F. A. Willers, and the paper includes a series of curves that will enable the designer to find, at a glance, the maximum torsional stress in a shaft of two diameters for various diameter and fillet proportions. It should be remarked that the results for a shaft of two diameters may be applied to most shafts of several diameters since the length of any two adjacent portions of the shaft are usually sufficiently long to make the analysis apply. Special shaft outlines, for instance shafts with oil throwers, can be investigated by the method.
Radiation in Boiler Furnaces
Authors: Broido B. N.
Published: January 2024

There is now a noticeable tendency toward an extensive application of water-cooled furnace walls for absorbing heat by radiation. An analysis of the fundamentals of radiation and of the effect of water-cooled walls on the gas temperatures in the furnace is given in this paper.

There is a certain relation between the amount of fuel burned, the surface exposed to direct radiation in the furnace, and the total heat absorbed by this surface. Curves are given showing this relation for different installations and a standard curve is drawn which enables the designer to determine with sufficient accuracy for practical purposes what part of the total heat generated in the furnace at different ratings is absorbed by the water-cooled walls. This curve can also be used to find the heat transmission by radiation per square foot of heating surface for any given condition of the furnace.

The amount of radiant-heat-absorbing surface that can be installed advantageously in a furnace depends upon the type of furnace and the kind of fuel burned. Based on a number of installations with water-cooled walls, the most advantageous arrangement of radiant-heat-absorbing surface for given conditions is suggested.

The effect of radiation from gases on heat transmission, particularly with high temperature differences, and the influence of radiation upon the measurement of gas temperature, are briefly discussed.
Fluid Flow in Pipes of Annular Cross-Section
Authors: Atherton D. H.
Published: January 2024

The object of the investigations reported in this paper was to determine the actual values of the friction coefficients for the flow of air, oil, and water through pipes of annular cross-section. The apparatus and method of testing are described and the data and results of the tests are given in graphic and tabular form. It appears that the coefficient of friction corresponding to any given turbulence factor for both turbulent and viscous flow has a value for pipes of annular cross-section slightly higher than for pipes of circular cross-section when determined by the equivalent-diameter formula.
Speed Changes of Hydraulic Turbines for Sudden Changes of Load
Authors: Strowger Earl B. , Kerr S. Logan
Published: January 2024

This paper shows how the variation in speed of hydraulic turbines due to sudden load changes may be determined by the application of the fundamental principles of water hammer with allowances for variation of turbine efficiency. The methods of determining governor time are noted. The relation of generator flywheel effect to speed variation is established and methods are indicated for the proper selection of these characteristics. Numerical examples are shown illustrating the speed changes for various load changes on a 70,000-hp. hydroelectric unit. The application to practical cases and the accuracy of approximate formulas are discussed.
Internal Friction in Solids
Authors: Kimball A. L. , Lovell D. E.
Published: January 2024

In connection with a test devised to determine quantitatively the amount of friction within the metal of a steel shaft, it was found that the internal frictional forces were totally unlike those of a viscous fluid, as assumed by many investigators, where the forces are greater the more rapid the deformation. Instead of this, the dissipative forces were found to be the same whatever the speed of deformation. The apparatus with which the tests were conducted is described, and the results are tabulated. Equations relating the variables involved are derived in the analysis of the problem.
The Lubrication of Waste-Packed Bearings
Authors: Karelitz G. B.
Published: January 2024

Since there is little published information in the technical literature on the mechanism of waste-packed bearings, the following paper based on results of an investigation on this subject made by the Westinghouse Electric and Manufacturing Company will be of interest.

The article discusses the feeding of oil through waste and the existence of a load carrying oil film in such bearings as essential for their proper performance. It gives observations on the friction and temperatures of these bearings and on the importance of proper packing to insure sealing the window by oil-saturated waste, and also discusses the existence of a critical oil lift at which the seal is broken. The reason for occasional end wear and scoring of the ends of a shell during the running-in period of service is given.
Heat Transfer for Forced Flow of Air at Right-Angles to Cylinders
Authors: Chappell E. L. , McAdams W. H.
Published: January 2024

For air flowing outside and at right-angles to single cylinders, published data are available covering extreme ranges of 120-fold for the coefficient of heat transfer, 250-fold for mass velocity, 1800-fold for diameter, and over 2-fold for film temperature in degrees fahrenheit absolute. Of the theoretical equations proposed by Boussinesq and King, that of the latter is far more in accord with these data. At the lower temperatures, the theoretical King equation gives predicted values in surprisingly good agreement with the data, in view of the rather questionable assumptions made during its derivation. The empirical equations of King for wires and of Rice for pipes agree well with the experimental values from which they were derived, but are not satisfactory when extrapolated to conditions for which they were not designed.

The method of plotting suggested by Davis has considerable promise, as does the rather complicated method of Rice involving the mean diameter of the effective film. No simple method was found for perfect correlation of the exact effect of each of the various factors. However, an empirical equation was developed and is recommended for practical use. For the high temperatures, where the exact effect of temperature is uncertain, the correction term for temperature was so chosen as to predict low rather than high values of the coefficient of heat transfer. The empirical equation involving the various factors is plotted in Fig. 8, thus making it unnecessary to substitute the values of the various factors in the recommended equation.

Data for staggered pipes are rather meager, but for a given mass velocity, diameter, and film temperature, the coefficients are somewhat higher than for single pipes. A simple method is suggested for estimating the increase due to staggering.
Heat Transfer Through Insulation in the Moderate- and High-Temperature Fields: A Statement of Existing Data
Authors: McMillan L. B.
Published: January 2024

The purpose of this paper is to set forth briefly the state of existing knowledge on heat transfer through insulating materials in the moderate- and high-temperature fields as indicated by the literature on the subject; to show in what respects this knowledge is insufficient; and to point out the directions in which future research work is most urgently needed.

This is not a review of the literature in the sense of attempting to abstract various articles and statements. No such attempt has been made, but after a comprehensive survey of the literature, the endeavor has been made to present a complete picture of the information available and to point out what is lacking. In addition the effort is made in some cases to supply needed information not now available in the literature. In this connection the method of determining mean temperatures, and the economic data in particular, are entirely new and original. Furthermore, the whole subject is presented from a new point of view.

The particular field of this research is the literature referring to heat transfer through insulation in the temperature range between the refrigeration field on the one hand and the refractories field on the other, with the specific exception of literature pertaining to heat transfer through building materials, which is covered by another National Research Council Heat Transfer Committee assignment, and which will be reported on separately by another author. Still other assignments cover the literature of heat transfer in the refractories field and in the refrigeration field. These likewise are being reported on by other authors.
Cycloidal Propulsion Applied to Aircraft
Authors: Kirsten Frederick Kurt
Published: January 2024

After reporting observations on the flight of gulls which indicated that the wing top moves with a cycloidal motion, the author proceeds to an analysis of this type of motion as it might be applied to the propulsion of aircraft. Various aspects of cycloidal propellers, including their efficiency, are discussed, and their application to heavier-than-air and lighter-than-air craft is urged. The advantages of this method of propulsion are discussed. Tests of model and full-size propellers are referred to, but are not included in the paper.
Railway Practices in Utilization and Conservation of Oil
Authors: Clark J. N.
Published: January 2024

In this paper the author mentions the growing competition of the airplane and motor vehicle and the manner in which the railroad is preparing to counteract that competition. Improvement in service, faster schedules, finer equipment, and safer and more efficient operation are among the most important steps taken by the roads. Fuel being the major item of expense, there is naturally a special effort to effect economy. This paper deals with oil fuel and. the methods employed by the railroads in its utilization. Early experiments are mentioned and a short treatise on production is given. The specifications laid down by the railroads are also given. Then follow discussions of methods of delivery and storage, fire hazard, locomotive equipment for the handling of the oil, such as heating, etc., methods of firing, construction of combustion space, refractories employed, etc. Some of the advantages of oil over other forms of fuel are also given. The final portion of the paper is devoted to a discussion of recent improvements in railroad power equipment, fuel-economy devices, increase in locomotive runs, and stationary boilers.
A Materials-Handling and Transport Organization
Authors: Fike C. A.
Published: January 2024

The paper outlines briefly the organization which has in charge the materials-handling activities of the Westinghouse Elec. & Mfg. Co. at East Pittsburgh. It describes the equipment used, the operation of it, and the methods of its control, and several of the wage-incentive plans which are used in the payment of the employees of the Plant Transportation Department. The paper concludes with a statement of some of the economies resulting from the organization described.
Photography as Used in Color Reproduction in the Graphic Arts: The Three-Color Theory of Vision—Making Photographic Materials Sensitive to Colors—Natural-Color Photographs—Color-Separation Negatives—Printing Processes—Modern Four-Color Printing Presses and Their Interesting Devices
Authors: Newton A. J.
Published: January 2024

Indications are that the demand for color in the graphic arts, produced by means of photography, will continue to increase, and this means that as the fundamental principles appear to be well established, further improvements will be made in machinery and materials and the skill in using them; and particularly in adjusting practice as closely as possible to theory, so that color reproduction, while maintaining the highest possible quality, will be produced more speedily and more economically.
Development of Welded Aircraft Construction
Authors: Clark S. C. , Gaston W. I.
Published: January 2024

In this paper the authors point out that steel tubing is coming into common use for fuselage construction and with this there is a trend toward general use of welding. It is desirable to establish standard designs for welded joints and to this end further research is needed. Suggestions are made for improvements in welding practice that will add safely and insure uniformly well-made welds.
The Selection of an Airplane Engine
Authors: Shoemaker J. M.
Published: January 2024

The author states that the commonly accepted fundamental requirements of an aircraft engine are: minimum weight per horsepower; maximum dependability, durability, and economy; minimum cost; and maximum ease of maintenance. He discusses the relative importance of these requirements, from the point of view of the airplane designer, in the power plants of various types of airplanes, and adds to them another requirement, namely, the consideration of an airplane engine as an integral part of an airplane.
Practical Determination of Torsional Vibration in an Engine Installation Which May Be Simplified to a Two-Mass System
Authors: Porter Frederic P.
Published: January 2024

This paper gives a practical solution for the torsional vibration in the shafting of a reciprocating-engine installation which may be reduced mathematically to a simple two-mass system. It presents methods for computing the damped vibrations in installations where the damping forces follow various laws. Particular attention is given to such damping forces as are caused by a marine propeller, elastic hysteresis, and a friction damper. The paper is illustrated by examples of computations for certain engine installations that have been investigated.
Study of Some Factors in Removal of Ash as Molten Slag From Powdered-Coal Furnaces
Authors: Sherman Ralph A. , Nicholls P. , Taylor Edmund
Published: January 2024

The purpose of this investigation, which was conducted at the Toronto, Ohio, station of the Pennsylvania-Ohio Power and Light Co., in cooperation with Stevens & Wood, Inc., New York, was to study those factors governing the application of the slagging method of ash removal which are related to the characteristics of the ash of the coal burned. The history of the development of and the merits of slagging furnaces are briefly discussed, and the results of observations made when burning three coals, whose ash had fluid temperatures of 2400, 2600, 2800 deg. fahr., in a furnace fired with horizontal burners and having bare water tubes set on three walls, are presented. The following studies were made: (1) The condition of the slag in the hearth and on tapping; (2) the temperature of the slag; (3) the temperature and composition of the gases near the slag bed; (4) the relation of the composition and fusion temperatures of the slag and the dust carried out of the furnace to those of the original ash; (5) the percentage of the ash fired which was carried out of the furnace and stack; (6) the relative temperatures of the gas entering the boiler tubes in two furnaces, one with a lower water-tube slag screen and the other with a slagging bottom; and (7) a brief study of the amount of flux necessary to add to a given ash to obtain a fluid slag.
Losses of Pressure Head Due to Sudden Enlargement of a Flow Cross-Section
Authors: Schutt H. C.
Published: January 2024

The exactness of the Borda-Carnot equation for the losses of energy in a liquid medium passing a discontinued cross-section—that is, a sudden enlargement—is discussed, the same formula is derived, based on one of the main principles in dynamics, and a report is given of experiments proving the validity of this formula.
Controlling the Manufacture of Parts on Order and for Stock by the Gantt Progress Chart
Authors: Porter David B.
Published: January 2024

This paper deals with two special applications of the Gantt progress chart in controlling production. The first shows the plan for the manufacture and assembly of parts on an order, and the progress of work in accordance with the plan. The arrangement of parts on this chart follows the natural order in the assembly of the product. The proper relationship of parts to each other and to the whole is made visible by a system of marginal indentations. This makes it possible to show by one line for each part the amount of stock on hand and in process, and the amount of time ahead or behind schedule. It also shows the time of starting work on each operation without the use of additional bars, thus condensing the chart.

The second chart is constructed essentially like the first one, but is designed for the case where manufacturing for stock is already in progress; that is, parts are being made both continuously and intermittently for continuous assembly at a uniform rate. This chart is designed to show the current condition of stores and parts in process, and the amount of time behind or ahead of schedule for each part and assembly. The method for laying out the chart is fully explained.

The function of such charts is to bring in advance to the attention of the executive those things which require action, and thereby eliminate the necessity of following up after delays have occurred. The charts measure the progress made on the manufacturing program, and in so doing they also serve as measures of executive ability.
Selective Package Conveyors
Authors: Hildreth W. O.
Published: January 2024

Severe competition is forcing every manufacturing industry to secure the most efficient layout of machinery and the maximum output from every square foot of floor space. Economical handling of materials, orders, letters, and instructions within the plant are important to secure the highest efficiency.

Conveyors of many types are now available, and “selective” conveyors are an important variety. These are adapted for automatically delivering packages or materials to various predetermined points selected by the sender at the time the material is dispatched.

The selection of destination may be determined by the size or weight of the package itself or by the position of a movable finger or selective pin. If the material to be transported is carried in trays or tote boxes over a conveyor system the movable selective finger can be mounted upon the upper front edge of the tray. This selective finger, for light service, may itself be used to deflect the tray from a conveyor by means of a switch bar, or may operate an electric circuit maker to control the movement of a heavy deflector bar.

The latest method of selection employs a separate pilot car carrying the selective pin and followed upon the conveyor belt by a string of boxes, cartons, or bags which are all going to the same destination. The procession is followed by a caboose car carrying a selective pin which releases the deflector bar after the caboose has passed and allows the deflector to swing out of the path of passing pilot cars until another car approaches with its selective pin in the proper position to operate this particular deflector.
Skid-Platform Shipment of Commodities
Authors: Shepard F. J.
Published: January 2024

After outlining the development of the use of lift trucks for interior factory transportation, the author briefly discusses their possibilities for interplant transportation and for use between cities through freight and motor-truck shipments. He shows how the methods of packing and transporting paper have been radically changed in the past two years through the use of skid platforms for shipment, and gives figures of savings effected in a number of instances.
Commercial Applications of High-Speed Oil Engines
Authors: Gibbons C. H.
Published: January 2024

The author discusses the possible application of high-speed Diesel engines to aircraft, trucks, and tractors, and gives details of their application to locomotives, generating sets for city buildings, cotton ginning, oil-well drilling, pipe-line pumping, irrigation, marine propulsion, air compressors, dredges, excavating machinery, etc. He also deals with medium-speed applications and gives data for use in estimating power costs.
What British Printers Are Doing to Encourage Research
Authors: Riddell John R.
Published: January 2024

The principal bodies of the printing trade in England have set up a Technical Bureau for gathering and pooling technical information and for the development and furthering of scientific research and investigation in technical problems.
Rolling Traction in Isoviscous-Rigid, Piezoviscous-Rigid, and Elastohydrodynamic Lubrication Regimes at Line Contact
Authors: Ohta Hiroyuki , Matsuyama Daisuke
Published: January 2024

This paper deals with rolling traction in isoviscous-rigid (IVR), piezoviscous-rigid (PVR), and elastohydrodynamic lubrication (EHL) regimes at line contact. First, a measuring method of rolling traction using the two-disk machine supported by ball bearings was explained. Then, the rolling traction in the IVR, PVR, and EHL regimes at line contact was measured. The measured results showed that as load P increases, the time average rolling traction FR AVG in the IVR and PVR regimes increases, while that in the EHL regime does not significantly increase. The measured FR AVG was lower than the rolling traction FR TED/CPA under the isothermal condition calculated by using the commercial software TED/CPA. To establish the rolling traction expression, a rolling traction expression under the isothermal condition FR iso was first derived by means of curve fitting the calculated FR TED/CPA. Then, a rolling traction expression (which takes into account the thermal effects of the inlet shear heating) FR thermal was derived by multiplying the thermal correction factor Ct to the expression FR iso. Finally, it was shown that the proposed expression FR thermal is effective for estimating the rolling traction in the IVR, PVR, and EHL regimes at line contact.
Tribocorrosion and Mechanical Properties of Nanotubes Grown on Ti–35Nb Alloy by Anodization
Authors: Luz Aline R. , de Lima Gabriel Goetten , Kasiorowski Tuany , de Souza Gelson B. , Lepienski Carlos M. , Grandini Carlos R. , Kuromoto Neide K. , Alves Ana Paula R.
Published: January 2024

In this study, we evaluated the tribocorrosion and mechanical properties of nanotubes grown on a Ti–35Nb alloy. The nanotube arrays, approximately 2.0 µm thick, were formed through controlled anodization and annealing, composed of Ti and Nb oxides. The compact oxide film at the nanotube/substrate interface provided corrosion resistance, lubricating properties in worn tracks, and improved wear resistance. The nanotubes exhibited a lower coefficient of friction, hardness, and elastic modulus compared to untreated Ti–35Nb. The crystalline structure of the nanotubes and the oxide interface layer enhanced adhesion, preventing plastic deformation and improving tribocorrosion resistance.
An Original Methodology to Model Stationary and Transient Starvation in Elastohydrodynamic Lubrication Contact
Authors: Decote M. , Fillot N. , Mahéo Y. , Morales-Espejel G. E.
Published: January 2024

Despite many researches in the past decades, starvation modeling of an elastohydrodynamic lubricated (EHL) contact is still an arduous task. The well-established Jackobson, Floberg, and Olsson (JFO) theory indeed shows jump discontinuities that are tricky to consider in a numerical solver. Two strategies are discussed in this article. The first one uses a penalty method, while the second one uses a moving mesh method. Their efficiency are compared to reference cases coming from the literature. Then, they are submitted to a transient analysis where the oil inlet layer decreases suddenly.
Atomic-Scale Insights Into Graphene/Fullerene Tribological Mechanisms and Machine Learning Prediction of Properties
Authors: Qiu Feng , Song Hui , Feng Weimin , Yang Zhiquan , Lu Ziyan , Hu Xianguo
Published: January 2024

Graphene/fullerene carbon–based nanoparticles exhibit excellent tribological properties in solid–liquid two-phase lubrication systems. However, the tribological mechanism still lacks profound insights into dynamic friction processes at the atomic scale. In this paper, the friction reduction and anti-wear mechanism of graphene/fullerene nanoparticles and the synergistic lubrication effect of the binary additive system were investigated by molecular dynamics simulations and tribological experiments. The friction performance was predicted based on six machine learning algorithms. The results indicated that in fluid lubrication, graphene promoted “liquid–liquid” interlayer sliding, whereas fullerene facilitated “solid–liquid” interface sliding, resulting in a decrease or increase in friction force. Under boundary lubrication, graphene/fullerene nanoparticles were adsorbed and anchored at the metal interface to form a physical protective film, which improved the bearing capacity of the lubricating oil film, transformed the direct contact between asperities into interlayer sliding of graphene and roll–slide polishing, filling, and repairing of fullerene, thus improving the frictional wear of the lubrication system as well as the friction temperature rise and stress concentration of the asperities. Furthermore, six machine learning algorithms showed low error and high precision, and the coefficient of determination was greater than 0.9, indicating that all models had good prediction and generalization capabilities, fully demonstrating the feasibility of combining molecular simulation and machine learning applications in the field of tribology.
Nature-Based or Traditional Kindergarten to Develop Fundamental Motor Skills? A Pilot Study
Authors: Pawlowski Charlotte Skau , Vibild Lammert Anne , Schipperijn Jasper , Toftager Mette
Published: January 2024

Environmental characteristics of kindergartens are important for the development of kindergarten-aged children. However, knowledge of the role of kindergarten play environments in developing children’s fundamental movement skills is limited. A pilot study was carried out to compare the fundamental movement skills of 3.5- to 5-year-old children in two kindergarten groups. One group had access to a traditional playground, an indoor room for active play, and had weekly trips. The other group had access to a nature-based playground. Fundamental movement skills were measured using the short form of the Bruininks-Oseretsky Test of Motor Proficiency, second edition test. In total, 28 children participated—11 children attended the kindergarten group with the traditional playground, and 17 children attended the kindergarten group with the nature-based playground. The total test score was 14.64 for children with access to a traditional playground and 16.71 for children with access to a nature-based playground. However, no statistically significant difference between the groups in total test score and the individual tests was found. It might be that space and diversity of features are more important than exposure to nature. In future research, more robust longitudinal studies with larger samples are required to investigate different kindergarten playground designs and environmental features related to motor skill development.
The induction of SHP-1 degradation by TAOK3 ensures the responsiveness of T cells to TCR stimulation
Authors: Poirier Alexandre , Ormonde João Vitor Silva , Aubry Isabelle , Abidin Belma Melda , Feng Chu-Han , Martinez-Cordova Zuzet , Hincapie Ana Maria , Wu Chenyue , Pérez-Quintero Luis Alberto , Wang Chia-Lin , Gingras Anne Claude , Madrenas Joaquín , Tremblay Michel L.
Published: January 2024

Thousand-and-one–amino acid kinase 3 (TAOK3) is a serine and threonine kinase that belongs to the STE-20 family of kinases. Its absence reduces T cell receptor (TCR) signaling and increases the interaction of the tyrosine phosphatase SHP-1, a major negative regulator of proximal TCR signaling, with the kinase LCK, a component of the core TCR signaling complex. Here, we used mouse models and human cell lines to investigate the mechanism by which TAOK3 limits the interaction of SHP-1 with LCK. The loss of TAOK3 decreased the survival of naïve CD4
+
T cells by dampening the transmission of tonic and ligand-dependent TCR signaling. In mouse T cells, Taok3 promoted the secretion of interleukin-2 (IL-2) in response to TCR activation in a manner that depended on
Taok3
gene dosage and on Taok3 kinase activity. TCR desensitization in

Taok3
−/−

T cells was caused by an increased abundance of Shp-1, and pharmacological inhibition of Shp-1 rescued the activation potential of these T cells. TAOK3 phosphorylated threonine-394 in the phosphatase domain of SHP-1, which promoted its ubiquitylation and proteasomal degradation. The loss of TAOK3 had no effect on the abundance of SHP-2, which lacks a residue corresponding to SHP-1 threonine-394. Modulation of SHP-1 abundance by TAOK3 thus serves as a rheostat for TCR signaling and determines the activation threshold of T lymphocytes.
Specific RNA structures in the 5′ untranslated region of the human cytomegalovirus major immediate early transcript are critical for efficient virus replication
Authors: Dickmander Bekah , Hale Andrew , Sanders Wes , Lenarcic Erik , Ziehr Ben , Moorman Nathaniel J.
Published: January 2024

These results reveal a new aspect of immediate early gene regulation controlled by non-coding RNA structures in viral mRNAs. Previous studies have largely focused on understanding viral gene expression at the level of transcriptional control. Our results show that a complete understanding of the control of viral gene expression must include an understanding of viral mRNA translation, which is driven in part by RNA structure(s) in the 5′ UTR of viral mRNAs. Our results illustrate the importance of these additional layers of regulation by defining specific 5′ UTR RNA structures regulating immediate early gene expression in the context of infection and identify important features of RNA structure that govern viral mRNA translation efficiency. These results may therefore broadly impact current thinking on how viral gene expression is regulated for human cytomegalovirus and other DNA viruses.
Lessons learnt from COVID-19 to reduce mortality and morbidity in the Global South: addressing global vaccine equity for future pandemics
Authors: Martin Rebecca , Maleche Allan , Gay Jill , Fatima Haram
Published: January 2024

COVID-19, which killed more than 6 million people, will not be the last pandemic. Vaccines are key to preventing and ending pandemics. Therefore, it is critical to move now, before the next pandemic, towards global vaccine equity with shared goals, intermediate steps and long-term advocacy goals. Scientific integrity, ethical development, transparency, accountability and communication are critical. Countries can draw on lessons learnt from their response to the HIV pandemics, which has been at the vanguard of ensuring equitable access to rights-based services, to create shared goals and engage communities to increase access to and delivery of safe, quality vaccines. Access can be increased by: fostering the spread of mRNA intellectual property (IP) rights, with mRNA vaccine manufacturing on more continents; creating price transparency for vaccines; creating easily understandable, accessible and transparent data on vaccines; creating demand for a new international legal framework that allows IP rights to be waived quickly once a global pandemic is identified; and drawing on scientific expertise from around the world. Delivery can be improved by: creating strong public health systems that can deliver vaccines through the lifespan; creating or strengthening national regulatory agencies and independent national scientific advisory committees for vaccines; disseminating information from reliable, transparent national and subnational surveillance systems; improving global understanding that as more scientific data become available, this may result in changes to public health guidance; prioritising access to vaccines based on scientific criteria during an epidemic; and developing strategies to vaccinate those at highest risk with available vaccines.
Concept Drift Adaptation by Exploiting Drift Type
Authors: Li Jinpeng , Yu Hang , Zhang Zhenyu , Luo Xiangfeng , Xie Shaorong
Published: January 2024

Concept drift is a phenomenon where the distribution of data streams changes over time. When this happens, model predictions become less accurate. Hence, models built in the past need to be re-learned for the current data. Two design questions need to be addressed in designing a strategy to re-learn models: which type of concept drift has occurred, and how to utilize the drift type to improve re-learning performance. Existing drift detection methods are often good at determining when drift has occurred. However, few retrieve information about how the drift came to be present in the stream. Hence, determining the impact of the type of drift on adaptation is difficult. Filling this gap, we designed a framework based on a lazy strategy called Type-Driven Lazy Drift Adaptor (Type-LDA). Type-LDA first retrieves information about both how and when a drift has occurred, then it uses this information to re-learn the new model. To identify the type of drift, a drift type identifier is pre-trained on synthetic data of known drift types. Furthermore, a drift point locator locates the optimal point of drift via a sharing loss. Hence, Type-LDA can select the optimal point, according to the drift type, to re-learn the new model. Experiments validate Type-LDA on both synthetic data and real-world data, and the results show that accurately identifying drift type can improve adaptation accuracy.
Explainability for Large Language Models: A Survey
Authors: Zhao Haiyan , Chen Hanjie , Yang Fan , Liu Ninghao , Deng Huiqi , Cai Hengyi , Wang Shuaiqiang , Yin Dawei , Du Mengnan
Published: January 2024

Large language models (LLMs) have demonstrated impressive capabilities in natural language processing. However, their internal mechanisms are still unclear and this lack of transparency poses unwanted risks for downstream applications. Therefore, understanding and explaining these models is crucial for elucidating their behaviors, limitations, and social impacts. In this article, we introduce a taxonomy of explainability techniques and provide a structured overview of methods for explaining Transformer-based language models. We categorize techniques based on the training paradigms of LLMs: traditional fine-tuning-based paradigm and prompting-based paradigm. For each paradigm, we summarize the goals and dominant approaches for generating local explanations of individual predictions and global explanations of overall model knowledge. We also discuss metrics for evaluating generated explanations and discuss how explanations can be leveraged to debug models and improve performance. Lastly, we examine key challenges and emerging opportunities for explanation techniques in the era of LLMs in comparison to conventional deep learning models.
Context-detail-aware United Network for Single Image Deraining
Authors: Hsu Wei-Yen , Lin Hsien-Wen
Published: January 2024

Images captured outdoors are often affected by rainy days, resulting in a severe deterioration in the visual quality of the captured images and a decrease in the performance of related applications. Therefore, single image deraining has attracted attention as a challenging research topic. Nowadays, there are two common deraining architectures in single image deraining. The first one is to restore the rain-free image by deducting rain streaks learned by the model from the rain image, but the background structure is easily mistaken for rain streaks and subtracted. The other one is to directly learn the clean background structure through the model using rain images, but it is difficult to completely remove the rain streaks due to the complexity of the information in images with rain. Therefore, current methods cannot balance rain streak removal and rain-free image background restoration in a single architecture and achieve good results. To address this issue, we propose a novel framework, namely, Context-Detail-Aware United Network (CDaUNet), which combines the above two architectures in this study. More specifically, we divide the restoration of the background structure of rain-free images and the learning of rain streaks into two independent sub-networks. The proposed Structure-Aware Rain Removal Network (SaRRN) is to learn the background structure in images to reconstruct clean rain-free images, whereas Detail-Aware Rain Streak Learning Network (DaRLN) is proposed to learn the details of rain streaks in images. Finally, we fuse the results generated by the two sub-networks through our designed Dual Architecture Fusion Network (DAFN) to reconstruct original rain images to effectively fuse the results of the two sub-networks. The experimental results show that CDaUNet achieves satisfactory performance in comparison with the state-of-the-art approaches included in rain streak removal and rain-free image structure restoration architectures on both synthetic and real image datasets, confirming the effectiveness of our method.
Finding Subgraphs with Maximum Total Density and Limited Overlap in Weighted Hypergraphs
Authors: Balalau Oana , Bonchi Francesco , Chan T-H. Hubert , Gullo Francesco , Sozio Mauro , Xie Hao
Published: January 2024

Finding dense subgraphs in large (hyper)graphs is a key primitive in a variety of real-world application domains, encompassing social network analytics, event detection, biology, and finance. In most such applications, one typically aims at finding several (possibly overlapping) dense subgraphs, which might correspond to communities in social networks or interesting events. While a large amount of work is devoted to finding a single densest subgraph, perhaps surprisingly, the problem of finding several dense subgraphs in weighted hypergraphs with limited overlap has not been studied in a principled way, to the best of our knowledge. In this work, we define and study a natural generalization of the densest subgraph problem in weighted hypergraphs, where the main goal is to find at most
k
subgraphs with maximum total aggregate density, while satisfying an upper bound on the pairwise weighted Jaccard coefficient, i.e., the ratio of weights of intersection divided by weights of union on two nodes sets of the subgraphs. After showing that such a problem is NP-Hard, we devise an efficient algorithm that comes with provable guarantees in some cases of interest, as well as, an efficient practical heuristic. Our extensive evaluation on large real-world hypergraphs confirms the efficiency and effectiveness of our algorithms.
Byzantine Agreement with Optimal Resilience via Statistical Fraud Detection
Authors: Huang Shang-En , Pettie Seth , Zhu Leqi
Published: January 2024

Since the mid-1980s it has been known that Byzantine Agreement can be solved with probability 1 asynchronously, even against an omniscient, computationally unbounded adversary that can adaptively
corrupt
up to
f < n/3
parties. Moreover, the problem is insoluble with
f ≥ n/3
corruptions. However, Bracha’s [
13
] 1984 protocol (see also Ben-Or [
8
]) achieved
f < n/3
resilience at the cost of
exponential
expected latency
2

Θ (
n
)

, a bound that has
never
been improved in this model with
f = ⌊ (n-1)/3 ⌋
corruptions.

In this article, we prove that Byzantine Agreement in the asynchronous, full information model can be solved with probability 1 against an adaptive adversary that can corrupt
f < n/3
parties, while incurring only
polynomial latency with high probability
. Our protocol follows an earlier polynomial latency protocol of King and Saia [
33
,
34
], which had
suboptimal
resilience, namely
f ≈ n
/10
9
 [
33
,
34
].

Resilience
f = (n-1)/3
is uniquely difficult, as this is the point at which the influence of the Byzantine and honest players are of roughly equal strength. The core technical problem we solve is to design a collective coin-flipping protocol that
eventually
lets us flip a coin with an unambiguous outcome. In the beginning, the influence of the Byzantine players is too powerful to overcome, and they can essentially fix the coin’s behavior at will. We guarantee that after just a polynomial number of executions of the coin-flipping protocol, either (a) the Byzantine players fail to fix the behavior of the coin (thereby ending the game) or (b) we can “blacklist” players such that the blacklisting rate for Byzantine players is at least as large as the blacklisting rate for good players. The blacklisting criterion is based on a simple statistical test of
fraud detection
.
Applications of Digital Pathology in Cancer: A Comprehensive Review
Authors: Omar Mohamed , Alexanderani Mohammad K. , Valencia Itzel , Loda Massimo , Marchionni Luigi
Published: January 2024

Digital pathology, powered by whole-slide imaging technology, has the potential to transform the landscape of cancer research and diagnosis. By converting traditional histopathological specimens into high-resolution digital images, it paves the way for computer-aided analysis, uncovering a new horizon for the integration of artificial intelligence (AI) and machine learning (ML). The accuracy of AI- and ML-driven tools in distinguishing benign from malignant tumors and predicting patient outcomes has ushered in an era of unprecedented opportunities in cancer care. However, this promising field also presents substantial challenges, such as data security, ethical considerations, and the need for standardization. In this review, we delve into the needs that digital pathology addresses in cancer research, the opportunities it presents, its inherent potential, and the challenges it faces. The goal of this review is to stimulate a comprehensive discourse on harnessing digital pathology and AI in health care, with an emphasis on cancer diagnosis and research.
Therapeutic Targeting of the Menin–KMT2A Interaction
Authors: Freire Pablo R. , Cutler Jevon A. , Armstrong Scott A.
Published: January 2024

The direct targeting of chromatin-associated proteins is increasingly recognized as a potential therapeutic strategy for the treatment of cancer. In this review, we discuss a prominent example, namely, small-molecule inhibitors that target the menin–KMT2A interaction. These molecules are currently being investigated in clinical trials and showing significant promise. We describe the unique specificity of menin–KMT2A protein complexes for the transcriptional regulation of a small subset of genes that drive developmental and leukemic gene expression. We review the chromatin-associated KMT2A complex and the protein–protein interaction between menin and KMT2A that is essential for the maintenance of different types of cancer cells, but most notably acute myeloid leukemia (AML). We also summarize the development of menin inhibitors and their effects on chromatin. Finally, we discuss the promising early results from clinical trials in patients with AML and the recent discovery of therapy-resistant menin mutants that validate menin as a therapeutic target but also may present therapeutic challenges.