bluuebunny/crossref_metadata_2025 huggingface dataset:
Two Slants on Postwar Wood Finishing: Part II—Suggested Method for Predicting Check Resistance of Lacquer Films
Authors: Smith W. T.
Published: July 2022

This paper presents details of equipment and technique for performing control tests on film-forming materials. Typical tests are interpreted and correlated, and illustrated examples are given of test results on various lacquers.
Current Design Practices for Gas-Turbine Power Elements
Authors: Emmert H. D.
Published: July 2022

A brief description is presented of certain principles of design and analysis for power elements of commercial gas-turbine plants. These principles are based upon the experience of the gas-turbine engineering group of the author’s company. The discussion comprises a review of procedures for analysis of turbine performance and design of blading and blade-carrying elements. Since the mechanical reliability and useful service life of a gas-turbine plant are governed almost entirely by the design of the power element, such a design must be a compromise between requirements for high efficiency, dependability, and low first cost. The fulfillment of these requirements is assisted by the organization of fundamental principles and experience into basic design practices.
Postwar Planning for Steam Capacity in Northern California
Authors: Whelchel C. C. , Johnson W. R.
Published: July 2022

The estimated population for northern and central California on January 1, 1949, was 4,950,000. This represents an increase since 1940, of 1,667,000 or about 51 per cent. The Pacific Gas and Electric system peak in 1940 was 1,125,000 kw. In December, 1948, it was 2,050,000 kw under daylight-saving time. Standard time would have added 160,000 kw. If the current trends continue, it is estimated the peak in 1951 will be 2,633,000 kw. Planning the required steam-generating capacity to carry its proper share of this unprecedented load growth is discussed in this paper.
Operating Characteristics of the 100,000-Kw Essex Turbine Generator
Authors: Neal Stanford , Renton Vinal S.
Published: July 2022

On December 18, 1947, the largest 3600-rpm tandem-compound steam-turbine generator ever built up to that-time was placed in service at the Essex Generating Station of the Public Service Electric and Gas Company, Newark, N. J. Since it was the first of a new class of turbine for both the manufacturer and the operating company, and since the throttle steam temperature was 1000 F, extensive tests were made to determine practical operation procedures for the new machine. These tests indicate that, even with the high steam conditions of 1250 psig this 1000 F turbine generator can safely withstand starting and loading rates higher than those normally used. The operating instructions for this machine can be revised to take advantage of these characteristics. Additional data are needed for wider application to other machines and designs.
Strength-Variance Studies of Plastics
Authors: Gailus W. J. , Yurenka Steven , Dietz A. G. H.
Published: July 2022

Preliminary work of the plastics research program at the Massachusetts Institute of Technology, sponsored by the Plastic Materials Manufacturers Association is reported. A statistical study of the effect of pertinent variables likely to be encountered in gathering mechanical data from a representative system of plastics (polymethyl methacrylate) is described. Effect of manufacturer, rate of test, and nature of test specimen is reported.
Instrumentation for Coal-Hydrogenation Service
Authors: Bruno G. L. , Geyer F. W. , Markovits J. A.
Published: July 2022

The process requirements of measurement and control are described as applied to high-pressure phases of the coal-hydrogenation process. Special emphasis is given to the details of development and application of special instruments.
A Simple Hydrodynamic Thrust Bearing
Authors: Archibald F. R.
Published: July 2022

Considerable mathematical difficulty has handicapped the designer in the application of the hydrodynamic theory of lubrication. This difficulty arises essentially from the shapes assumed by the oil films. In 1918 Lord Rayleigh gave a detailed analysis of the simple slider bearing, neglecting the side-leakage effect, in which he determined that the greatest load capacity occurs when the slider element gives a stepped convergence to the oil film. From the simple geometry of this oil film, a solution, taking account of side leakage, might be obtained fairly easily. The author proves this to be so, and gives solutions for the case of rectilinear motion with finite bearing width, and also the more practical sectorial case of a thrust bearing.
A Mathematical Evaluation of Pressures in a Grease-Lubricated Bearing
Authors: Lawrence K. B.
Published: July 2022

Of the various methods proposed in the past for the numerical evaluation of pressures developed in a film of lubricant, perhaps the best method, in general, consists of the application of a finite-difference formula developed from the fundamental differential equation. Such a formula has been developed by Derman G. Christopherson (1), who also has shown that the formula gives accurate results when applied to calculations involving oil-lubricated bearings. The author herein applies the finite-difference formula to calculations of the pressure distribution existing in a grease-lubricated bearing and compares the results obtained with the results of a recent experimental investigation by Cohn and Oren (2), which was conducted under similar conditions of operation.
Heat Transfer to Superheated Steam at High Pressures
Authors: McAdams W. H. , Kennel W. E. , Addoms J. N.
Published: July 2022

Local coefficients of heat transfer from a 12.3-in. length of 0.252-in. tubing to steam flowing upward in a vertical annulus were measured for pressures from 115 to 3500 psia, for temperatures from 430 to 1000 F, and for temperature differences from 100 to 620 F. All results are correlated in Fig. 8 in terms of the local Nusselt number, the Reynolds number, the Prandtl number, and the geometrical ratio L/Dc with the physical properties evaluated at the film temperature. An improved correlation, employing new data on thermal conductivity, is presented in Fig. 10 of the Addendum.
Vibration of Marine-Turbine Blading
Authors: Nolan R. W.
Published: July 2022

The purpose of this paper is to give a general explanation of the vibration phenomena encountered in turbine design. Detailed methods have been omitted. The behavior of a vibrating cantilever is expressed in terms of the exciting force and damping factor. The sources of damping and excitation are discussed. Impulse excitation is briefly considered and the reasons for its devastating effects are shown. The procedure of tuning low-pressure blading, to avoid resonance at the lower harmonics of the turbine speed, is explained in considerable detail. An apparatus for determining the natural frequency of blading, and another for applying both tensile and alternating bending stresses simultaneously, are described. The direct tensile stress in the test is plotted versus the alternating bending stress which causes failure, thus obtaining a curve which shows the resistance of the blade to any combination of these stresses. The designed stresses for certain turbine blades and the stresses involved in several blade failures have been plotted on this diagram for purposes of comparison.
Feedwater Treatment During Early Operation of Steam-Electric Stations
Authors: Alexander R. C. , Rummel J. K.
Published: July 2022

Based upon the experience with five high-pressure steam-generating units installed at the Harbor Steam Plant of the City of Los Angeles during the last six years, the authors devise some basic practices to follow during early operation of such installations. Their study includes such items as cleaning the feed system, corrosion prevention, chemical control of corrosion, sampling and control tests of the feedwater system, and inspection of equipment.
Effect of Size on the Design and Performance of Internal-Combustion Engines
Authors: Taylor C. F.
Published: July 2022

The importance of the problem is outlined and size effects isolated from other effects. Three similar engines were tested at the Sloan Laboratories at M.I.T. Mechanical stresses, volumetric efficiency, heat losses, and wall temperatures are explained as a function of cylinder size. The effects of cylinder size on combustion and fuel requirements are pointed out.
Accelerated-Cavitation Research
Authors: Rheingans W. J.
Published: July 2022

The cavitation-pitting tests described in this paper were made with an accelerated-cavitation machine of the vibratory type. An attempt was made to solve some of the phenomena of cavitation by varying the amplitude of vibration, by varying the depth of submergence of the test specimen in the test liquid, and by using alkalis, acids, and oils for the test liquid. Other tests were made to determine the relative resistance to pitting of recently developed materials and techniques for applying these materials. Results showed that accelerated-cavitation tests can be used to determine some of the mechanics of cavitation, as well as to indicate that some of the newly developed materials might be suitable for use on hydraulic machinery under operating conditions where cavitation occurs.
Zero-Pressure Thermodynamic Properties of Carbon Monoxide and Nitrogen
Authors: Goff J. A. , Gratch Serge
Published: July 2022

In this report are presented tables of the principal thermodynamic properties of carbon monoxide and of nitrogen along the zero-pressure isobar in the range 100 to 5000 deg R at the intervals indicated by the numbers in parentheses as follows: 100[5]130[10]240[20]500[50]1000[100]2000[200]5000. The data have been computed by the method of quantum statistical mechanics in the University of Pennsylvania Thermodynamics Research Laboratory under Project G-3. Computational accuracy well beyond present physical accuracy has been maintained for practical reasons. It is believed that the tables given herein should supersede all previous ones. The calculated values are in satisfactory agreement with those obtained from calorimetric and acoustic velocity measurements.
The Thermodynamic Properties of Helium
Authors: Akin S. W.
Published: July 2022

Evaluation has been made of the density, enthalpy, entropy, viscosity, and thermal conductivity of helium in the range of pressures from atmospheric to 6000 psia and at temperatures from −440 F to 600 F. These data are composed of observed values published prior to 1945, and of extrapolations based upon the Beattie-Bridgeman equation of state and kinetic theory. The results evaluated to four significant figures are tabulated for particular values of pressure and temperature. Graphic plots of the same information are also presented, with an accuracy sufficient for investigations of flow and heat-transfer processes involving high-pressure helium.
Compilation of Thermal Properties of Wind-Tunnel and Jet-Engine Gases at the National Bureau of Standards
Authors: Hoge Harold J.
Published: July 2022

A project for the preparation of a series of tables of thermal properties of gases is described. This project was undertaken by the National Bureau of Standards at the suggestion and with the co-operation of the National Advisory Committee for Aeronautics. The scope of the project, tables now available, work in progress, and plans for the future are described. The lack of adequate data at high temperatures and also at high pressures is pointed out.
Pressure Drop and Convective Heat Transfer With Surface Boiling at High Heat Flux; Data for Aniline and n-Butyl Alcohol
Authors: Kreith Frank , Summerfield Martin
Published: July 2022

Heat-transfer coefficients to commercial-grade aniline and n-butyl alcohol have been measured at high rates of heat flux. Data have been obtained for both of the liquids in the heat-flux range from 0.3 to 3 Btu/sq in. sec and in the pressure range from 30 to 400 psia at velocities from 20 to 40 fps. The test section consisted of a ½-in-ID stainless-steel tube which was heated electrically.
The Evaluation of Steam-Power-Plant Losses by Means of the Entropy-Balance Diagram
Authors: Keller Allen
Published: July 2022

This paper deals with a method of isolating and evaluating the various cycle losses of a condensing steam power plant. Each loss in the steam cycle causes an increase of entropy. By considering each of these entropy increases on a “per hour” basis instead of a “per pound” basis, the heat rejection to the condenser caused by each individual loss can be evaluated quickly.
Head and Flow Observations on a High-Efficiency Free Centrifugal-Pump Impeller
Authors: Osborne W. C. , Morelli D. A.
Published: July 2022

A series of studies of the flow through the various components of hydrodynamic machinery is in progress in the Hydraulic Machinery Laboratory of the California Institute of Technology. Observations have been made on an impeller patterned after the Grand Coulee design. The impeller was operated as an isolated unit hydraulically free of the casing. The flow pattern at the discharge has been determined quantitatively for one flow rate, and a head-capacity curve for the impeller has been obtained. This paper constitutes a report on the findings up to the present.
Heat-Transfer and Flow-Friction Characteristics of Some Compact Heat-Exchanger Surfaces: Part 2—Design Data for Thirteen Surfaces
Authors: Kays W. M. , London A. L.
Published: July 2022

New developments in prime-mover and process equipment have created a greater need for compact heat-transfer surfaces. This paper presents basic heat-transfer and flow-friction design data for thirteen such surfaces which may be described generally as the plate-fin type and finned-flat-tube type. In addition to the use of the conventional nondimensional correlations, the various surfaces are compared on heat-transfer coefficient versus flow-friction-horsepower basis.
The Evolution and Impact of Human Confidence in Artificial Intelligence and in Themselves on AI-Assisted Decision-Making in Design
Authors: Chong Leah , Raina Ayush , Goucher-Lambert Kosa , Kotovsky Kenneth , Cagan Jonathan
Published: July 2022

Decision-making assistance by artificial intelligence (AI) during design is only effective when human designers properly utilize the AI input. However, designers often misjudge the AI’s and/or their own ability, leading to erroneous reliance on AI and therefore bad designs occur. To avoid such outcomes, it is crucial to understand the evolution of designers’ confidence in both their AI teammate(s) and themselves during AI-assisted decision-making. Therefore, this work conducts a cognitive study to explore how to experience various and changing (without notice) AI performance levels and feedback affects these confidences and consequently the decisions to accept or reject AI suggestions. The results first reveal that designers’ confidence in an AI agent changes with poor, but not with good, AI performance in this work. Interestingly, designers’ self-confidence initially remains unaffected by AI accuracy; however, when the accuracy changes, self-confidence decreases regardless of the direction of the change. Moreover, this work finds that designers tend to infer flawed information from feedback, resulting in inappropriate levels of confidence in both the AI and themselves. Confidence in AI and self-confidence are also shown to affect designers’ probability of accepting AI input in opposite directions in this study. Finally, results that are uniquely applicable to design are identified by comparing the findings from this work to those from a similar study conducted with a non-design task. Overall, this work offers valuable insights that may enable the detection of designers’ dynamic confidence and their consequent misuse of AI input in the design.
Genoprotolichus tilae sp. nov. (Acariformes: Pterolichidae), a new feather mite species from Psittacara leucophthalmus (Müller PLS) (Psittacidae) in Brazil
Authors: Hernandes Fabio Akashi
Published: July 2022

A new feather mite species Genoprotolichus tilae sp. nov. is described from the white-eyed parakeet, Psittacara leucophthalmus (Müller PLS, 1776) (Psittaciformes: Psittacidae), from Brazil. A list of pterolichid mite genera associated with parrots (Prittaciformes) is presented, and data on Genoprotolichus species recorded from the New World are summarized. Some diagnostic features (scapular setae) of all previously described species of the genus Genoprotolichus are presented.
Thermal stability of band offsets of NiO/GaN
Authors: Xia Xinyi , Li Jian-Sian , Chiang Chao-Ching , Yoo Timothy Jinsoo , Ren Fan , Kim Honggyu , Pearton S. J.
Published: July 2022

NiO is a promising alternative to p-GaN as a hole injection layer for normally-off lateral transistors or low on-resistance vertical heterojunction rectifiers. The valence band offsets of sputtered NiO on c-plane, vertical geometry homoepitaxial GaN structures were measured by x-ray photoelectron spectroscopy as a function of annealing temperatures to 600 °C. This allowed determination of the band alignment from the measured bandgap of NiO. This alignment was type II, staggered gap for both as-deposited and annealed samples. For as-deposited heterojunction, ΔEV = 2.89 eV and ΔEC = −2.39 eV, while for all the annealed samples, ΔEV values were in the range of 3.2–3.4 eV and ΔEC values were in the range of −(2.87–3.05) eV. The bandgap of NiO was reduced from 3.90 eV as-deposited to 3.72 eV after 600 °C annealing, which accounts for much of the absolute change in ΔEV − ΔEC. At least some of the spread in reported band offsets for the NiO/GaN system may arise from differences in their thermal history.
The effect of age and hearing sensitivity at frequencies above 8 kHz on auditory stream segregation and speech perception
Authors: Jain Saransh , Narne Vijaya Kumar , Nataraja N. P. , Madhukesh Sanjana , Kumar Kruthika , Moore Brian C. J.
Published: July 2022

The effects of age and mild hearing loss over the extended high-frequency (EHF) range from 9000 to 16 000 Hz on speech perception and auditory stream segregation were assessed using four groups: (1) young with normal hearing threshold levels (HTLs) over both the conventional and EHF range; (2) older with audiograms matched to those for group 1; (3) young with normal HTLs over the conventional frequency range and elevated HTLs over the EHF range; (4) older with audiograms matched to those for group 3. For speech in quiet, speech recognition thresholds and speech identification scores did not differ significantly across groups. For monosyllables in noise, both greater age and hearing loss over the EHF range adversely affected performance, but the effect of age was much larger than the effect of hearing status. Stream segregation was assessed using a rapid sequence of vowel stimuli differing in fundamental frequency (F0). Larger differences in F0 were required for stream segregation for the two groups with impaired hearing in the EHF range, but there was no significant effect of age. It is argued that impaired hearing in the EHF range is associated with impaired auditory function at lower frequencies, despite normal audiometric thresholds at those frequencies.
Tracking and classifying Amazon fire events in near real time
Authors: Andela Niels , Morton Douglas C. , Schroeder Wilfrid , Chen Yang , Brando Paulo M. , Randerson James T.
Published: July 2022

Exceptional fire activity in 2019 sparked concern about Amazon forest conservation. However, the inability to rapidly separate satellite fire detections by fire type hampered fire suppression and assessment of ecosystem and air quality impacts. Here, we describe the development of a near–real-time approach for tracking contributions from deforestation, forest, agricultural, and savanna fires to burned area and emissions and apply the approach to the 2019 fire season in South America. Across the southern Amazon, 19,700 deforestation fire events accounted for 39% of all satellite active fire detections and the majority of fire carbon emissions (63%; 69 Tg C). Multiday fires accounted for 81% of burned area and 92% of carbon emissions from the Amazon, with many forest fires burning uncontrolled for weeks. Most fire detections from deforestation fires were correctly identified within 2 days (67%), highlighting the potential to improve situational awareness and management outcomes during fire emergencies.
Landscape-scale giant panda conservation based on metapopulations within China’s national park system
Authors: Xu Yu , Yang Biao , Dai Qiang , Pan Han , Zhong Xue , Ran Jianghong , Yang Xuyu , Gu Xiaodong , Yang Zhisong , Qi Dunwu , Hou Rong , Zhang Zejun
Published: July 2022

Historically, giant panda conservation in China has been compromised by disparate management of protected areas. It is thus crucial to address how giant panda populations can be managed cohesively on a landscape scale, an opportunity offered by China’s newly established Giant Panda National Park. Here, we evaluated giant panda populations in a metapopulation context, based on range-wide data from the Fourth National Giant Panda Survey. We delineated metapopulations by geographic range, relative abundance, and relative density and assessed the extent of human disturbance each metapopulation faced. We found density-dependent and disturbance-influenced effects on habitat selection across metapopulations. We determined the main effects faced by each metapopulation regarding area sensitivity, population size, intraspecific competition, and disturbance. To enhance the landscape-scale conservation of giant pandas and various other wildlife across China’s national park system, we propose that metapopulation management incorporates population status along with density-dependent and disturbance-related effects on habitat selection.
Self-adaptive virtual microchannel for continuous enrichment and separation of nanoparticles
Authors: Yang Yang , Zhang Lin , Jin Ke , He Meihang , Wei Wei , Chen Xuejiao , Yang Qingrui , Wang Yanyan , Pang Wei , Ren Xiubao , Duan Xuexin
Published: July 2022

The transport, enrichment, and purification of nanoparticles are fundamental activities in the fields of biology, chemistry, material science, and medicine. Here, we demonstrate an approach for manipulating nanospecimens in which a virtual channel with a diameter that can be spontaneously self-adjusted from dozens to a few micrometers based on the concentration of samples is formed by acoustic waves and streams that are triggered and stabilized by a gigahertz bulk acoustic resonator and microfluidics, respectively. By combining a specially designed arc-shaped resonator and lateral flow, the in situ enrichment, focusing, displacement, and continuous size-based separation of nanoparticles were achieved, with the ability to capture 30-nm polystyrene nanoparticles and continuously focus 150-nm polystyrene nanoparticles. Furthermore, exosome separation was also demonstrated. This technology overcomes the limitation of continuously manipulating particles under 200 nm and has the potential to be useful for a wide range of applications in chemistry, life sciences, and medicine.
Artificially steering electrocatalytic oxygen evolution reaction mechanism by regulating oxygen defect contents in perovskites
Authors: Lu Min , Zheng Yao , Hu Yang , Huang Bolong , Ji Deguang , Sun Mingzi , Li Jianyi , Peng Yong , Si Rui , Xi Pinxian , Yan Chun-Hua
Published: July 2022

The regulation of mechanism on the electrocatalysis process with multiple reaction pathways is more efficient and essential than conventional material engineering for the enhancement of catalyst performance. Here, by using oxygen evolution reaction (OER) as a model, which has an adsorbate evolution mechanism (AEM) and a lattice oxygen oxidation mechanism (LOM), we demonstrate a general strategy for steering the two mechanisms on various La

x

Sr

1−
x

CoO
3−δ
. By delicately controlling the oxygen defect contents, the dominant OER mechanism on La

x

Sr

1−
x

CoO
3−δ
can be arbitrarily transformed between AEM-LOM-AEM accompanied by a volcano-type activity variation trend. Experimental and computational evidence explicitly reveal that the phenomenon is due to the fact that the increased oxygen defects alter the lattice oxygen activity with a volcano-type trend and preserve the Co
0
state for preferably OER. Therefore, we achieve the co-optimization between the activity and stability of catalysts by altering the mechanism rather than a specific design of catalysts.
Supplemental Material: Petrogenesis of arsenic and platinum-group minerals from a partially serpentinized dunite in East Dover, Vermont, USA
Authors: Brigham John M. , Baldwin Suzanne
Published: July 2022

Table S1: Major element X-ray fluorescence whole-rock geochemical analyses in weight percent. Table S2: Trace element X-ray fluorescence whole-rock geochemical analyses in parts per million. Table S3: Electron microprobe analyses of olivine from meta-dunite in East Dover Vermont. Table S4: Electron microprobe analyses of chrome spinel from East Dover, Vermont, in weight percent. Table S5: Electron microprobe analyses of sulfide minerals from meta-dunite in East Dover, Vermont, in weight percent. Table S6: Coordinates of key sample localities.
Humeral periosteal spur sign with osteolysis as an early radiographic indicator of low-gradeCutibacterium acnesprosthetic shoulder infection
Authors: Bauer Stefan , Dietz Benjamin , Trampuz Andrej , Marchetti Oscar
Published: July 2022

The early diagnosis of low-gradeCutibacterium acnesprosthetic shoulder joint infection is challenging due to the lack of clinical and laboratory signs. Patients present with atypical symptoms such as stiffness or failure to improve shoulder function. The diagnosis is often delayed with impact on long-term outcomes. We present the case of an 82-year-old man with a surgical site erythema occurring 7 weeks after reverse shoulder arthroplasty associated with a light raise of C reactive protein (20 mg/L). At 9 weeks, radiographs revealed a ‘periosteal spur sign’ (humeral calcar) and localised adjacent osteolysis. Open surgery showed morphological signs of infection confirmed by growth ofC.acnesin eight cultures. A ‘periosteal spur sign’ is a useful early radiographic indicator of low-grade prosthetic joint infection usually occurring with some delay after clinical symptoms. A high clinical index of suspicion is needed to proceed with biopsies and to initiate combined operative and antibacterial treatment.
‘Vanishing’ fragmented potential at the epicardium in a patient with Brugada syndrome
Authors: Hayashi Tatsuya , Sekiguchi Yukio , Yamamoto Shingo , Fujita Hideo
Published: July 2022

A man in his 40s with Brugada syndrome underwent catheter ablation for ventricular fibrillation. When we performed epicardial mapping again to check for residual ablation sites after ablation, a remarkable reproducible fragmented potential was observed at the anterior aspect of the right ventricle using an Advisor HD Grid (Abbott), which had not been detected during the initial mapping before ablation, and which was invisible to the ablation catheter. Fluoroscopic imaging demonstrated a shiny area anterior to the heart, suggesting trapped air, presumed to have arisen when the sheath was inserted into the pericardial space. The air trapped between the heart and pericardium prevented the HD grid from contacting the epicardium, resulting in the recording of a fragmented potential. The trapped air was removed manually via the sheath, and the potential vanished. When fragmented potentials are observed at the anterior right ventricle (RV) in the epicardium, air trapping should be ruled out by fluoroscopy.
Discovery of a rare aberrant artery overlying trachea during open tracheostomy
Authors: Tai Man Ting Florence , Lui Siu Kuen
Published: July 2022

Tracheostomy is a common surgical procedure for securing a patent airway. Anatomical variations of major vessels overlying the trachea may pose significant bleeding risk during the procedure. Hence, thorough preoperative assessment of the neck and surgeon’s intraoperative vigilance are essential. Open tracheostomy is a safer option than percutaneous dilatational tracheostomy. Extra caution with stoma wound care and change of tracheostomy tube are necessary postoperatively if any major vessel is detected in close proximity with the tracheal stoma.
The face of Smith-Magenis syndrome: a subjective and objective study
Authors: Allanson Judith E , Greenberg Frank , Smith Ann C M
Published: July 2022

We report a study of 55 subjects with Smith-Magenis syndrome, aged 9 months to 35 years. Each person has been evaluated with an assessment of “gestalt” and detailed facial measurement, using previously published methodology, with compilation of Z score pattern profiles.

The facial phenotype of SMS is quite distinctive, even in the young child. The overall face shape is broad and square. The brows are heavy, with excessive lateral extension of the eyebrows. The eyes slant upwards and appear close set and deep set. The nose has a depressed root and, in the young child, a scooped bridge. With time, the bridge becomes more ski jump shaped. The height of the nose is markedly reduced while the nasal base is broad and the tip of the nose is full. The shape of the mouth and upper lip are most distinctive. The mouth is wide with full upper and lower lips. The central portion of the upper lip is fleshy and everted with bulky philtral pillars, producing a tented appearance that, in profile, is striking. With age, mandibular growth is greater than average and exceeds that of the maxilla. This leads to increased jaw width and protrusion and marked midface hypoplasia.

Craniofacial pattern analysis supports these subjective impressions. After mid-childhood, mandibular dimensions consistently exceed their maxillary counterparts. Craniofacial widths are greater than corresponding depths and heights. Nasal height is reduced while nasal width is increased. There is mild brachycephaly. The most marked age related changes are increased width of the nose and lower face (mandibular width) with reduction in nasal height and midfacial depth.
A quest for the origin of the Sagnac effect
Authors: Bhadra Arunava , Ghose Souvik , Raychaudhuri Biplab
Published: July 2022

In the literature, there is no consensus on the origin of the relativistic Sagnac effect, particularly from the standpoint of the rotating observer. The experiments of Wang et al. (Phys Lett A 312(1–2):7, 2003; Phys Rev Lett 93(14):143901, 2004) has, however, questioned the pivotal role of rotation of the platform in Sagnac effect. Recently, the relative motion between the reflectors which force light to propagate along a closed path and the observer has been ascribed as the cause of the Sagnac effect. Here, we propose a thought experiment on linear Sagnac effect and explore another one proposed earlier to demonstrate that the origin of the Sagnac effect is neither the rotation of frame affecting clock synchronization nor the relative motion between the source and the observer; Sagnac effect originates purely due to asymmetric position of the observer with respect to the light paths. Such a conclusion is validated by analysis of a gedanken Sagnac kind experiment involving rotation.
Protecting high-dimensional entanglement from decoherence via quantum weak measurement and reversal
Authors: Feng Kun-Hong , Chen Yu-Chi , Zhou Ping
Published: July 2022

High-dimensional quantum communication plays an important role in long-distance quantum communication. It is shown that two-qubit quantum entanglement can be protected from amplitude damping decoherence. We study the effect of amplitude damping decoherence on two-qubit high-dimensional quantum entanglement. The negativity for high-dimensional quantum entanglement with or without quantum weak measurement and the reversal in amplitude damping decoherence are presented. We found that nonmaximally entangled state may have better performance than maximally entangled state in amplitude damping decoherence. Moreover, we show that arbitrary high-dimensional quantum entanglement can be protected from amplitude damping decoherence by weak measurement and the reversal. The results of our protocol are in agreement with previous analysis for the case of qubits and qutrits.
Koo and Kleinstreuer–Li correlation and modified Buongiorno model on unsteady radiative non-Newtonian fluid flow
Authors: Alsaiari Abdulmohsen O. , Iqbal Ahmed , Abulkhair Hani , Gzara Lassaad , Almatrafi Eydhah , Kumar Ranvijay , Suresha S.
Published: July 2022

This research paper investigates the heat and mass transport characteristics in an unsteady flow of Maxwell nanofluid (NF). While examining heat transfer properties, thermal radiation is taken into account. Further, copper oxide with water-based NF is considered. The mass transfer and effective thermal conductivity of nanofluid flow are scrutinized by Koo and Kleinstreuer–Li (KKL) NF model. Through apt transformations, relevant flow expressions are converted to ordinary differential equations (ODEs). The numerical approach Runge–Kutta–fourth–fifth Fehlberg’s order process (RKF-45) algorithm with shooting technique is utilized to solve the generated ODEs. Results reveal that, the rise in values of unsteadiness parameter has a positive impact on both concentration and thermal profiles. The Deborah number has constructive impact on heat transport and reverse influence on velocity field. The improved heat transport is seen for augmented values of radiation and heat source/sink parameters. The Brownian motion parameter has positive influence on heat transport and reverse effect on mass transport.
Bifurcation Analysis for Two-Species Commensalism (Amensalism) Systems with Distributed Delays
Authors: Li Tianyang , Wang Qiru
Published: July 2022

This paper is devoted to studying the dynamics of two-species commensalism (amensalism) systems with delays. We first study the system with a distributed delay but without the discrete delay, investigate the local stabilities of equilibria and prove the existence of transcritical bifurcation. Then, we study the system with a discrete delay and a distributed delay. By analyzing the characteristic equation of the positive equilibrium and regarding the discrete delay as the bifurcation parameter, we show the existence of periodic solutions bifurcating from the positive equilibrium. Also, we derive the precise formulae to determine the Hopf bifurcation direction and the stability of the bifurcating periodic solutions by using the normal form theory and the center manifold theorem. Numerical simulation results are also included to support our theoretical analysis.
Bifurcation Analysis of Multiscale Malaria Model with Serratia AS1 Bacteria and Saturated Treatment
Authors: Wang Jing , Zhao Hongyong
Published: July 2022

Recent experimental results have implied that Serratia AS1 bacteria efficiently suppress the development of P. falciparum, and rapidly disseminate via vertical transmission and sexual transmission throughout mosquito population. In this paper, we propose a new malaria model to investigate the roles of saturated treatment and AS1 bacteria in malaria transmission. One feature of the model is that human and mosquito populations dynamics run on disparate temporal scales. Singular perturbation techniques are used for the separation of fast and slow dynamics. It also enables us to overcome the difficulties of exploring bifurcations in higher dimensional system. We demonstrate that the reduced systems may undergo backward bifurcation, Hopf bifurcation and Bogdanov–Takens bifurcation of codimension 2, which indicates that the delayed effect for treatment has important implications for malaria control. Numerical simulations substantiate these analytical results and show epidemiological insights. Finally, the model without AS1 bacteria transmission is applied to simulate the accumulative malaria cases in Burundi. We observe that malaria may not be eliminated by a single control in Burundi. A variety of available control measures should be adopted to eradicate malaria, such as improving treatment rate, reducing the delayed effect for treatment, and possibly releasing mosquitoes that carry AS1 bacteria.
Compound Chaotic Systems with Composite Attractors
Authors: Tiwari Ankit , Roy Binoy Krishna
Published: July 2022

Chaotic systems with either a self-excited attractor or a hidden attractor are prevalent in the research paradigm. But a composite attractor of a chaotic system that exhibits both self-excited attractors and hidden attractors with time is rare. Compounding of a chaotic system is devised to enhance the richness of the system as it exhibits different behaviors with time. This paper presents a two-stage technique for generating a compound-chaotic system by combining eight subsystems from Chameleon chaotic system. The first stage is the design of a nonautonomous piecewise function. The second stage is to generate a compound system using the designed function. The compound system exhibits a composite attractor that is a mix of self-excited and hidden attractors with time. The composite attractor is generated with the variation of the equilibrium points in the eight subsystems due to the designed function. The resultant attractor of the compound-chaotic system is termed as a composite attractor since it has both the self-excited and hidden attractors. Transient chaos and coexistence of attractors are also observed in the system. The proposed compound-chaotic system is analyzed using the available tools and the paper’s claims are validated.
On one-relator groups and units of special one-relation inverse monoids
Authors: Nyberg-Brodda Carl-Fredrik
Published: July 2022

This paper investigates and clarifies some connections between the theory of one-relator groups and special one-relation inverse monoids, i.e. those inverse monoids with a presentation of the form [Formula: see text]. We show that every one-relator group admits a special one-relation inverse monoid presentation. We subsequently consider the classes [Formula: see text] of one-relator groups which can be defined by special one-relation inverse monoid presentations in which the defining word is arbitrary; reduced; cyclically reduced; or positive, respectively. We show that the inclusions [Formula: see text] are all strict. Conditional on a natural conjecture, we prove [Formula: see text]. Following this, we use the Benois algorithm recently devised by Gray and Ruškuc to produce an infinite family of special one-relation inverse monoids which exhibit similar pathological behavior (which we term O’Haresque) to the O’Hare monoid with respect to computing the minimal invertible pieces of the defining word. Finally, we provide a counterexample to a conjecture by Gray and Ruškuc that the Benois algorithm always correctly computes the minimal invertible pieces of a special one-relation inverse monoid.
Dominating the Wild: How Have Companies Been Leveraging Cryptoeconomics to Shape Markets Through Business Model Innovation?
Authors: Araújo Allysson Allex , Soares Pamella , Saraiva Raphael , Câmara Samuel , Souza Jerffeson
Published: July 2022

A recent emerging market that has impacting companies, customers, and society is the one embedded in Cryptoeconomics. However, although promising, management research has been scarce in drawing the Business Model Innovation (BMI) based on Cryptoeconomics as a new market, including its theoretical underpinnings. Acknowledging both the research gap and the practical relevance of market representations and business models in the market shaping phenomenon, we conduct a pioneering empirical study to investigate how forward-looking firms have practiced Cryptoeconomics to shape new markets through BMI. As significant contributions, (i) we provide a conceptual framework to clarify the market shaping process led by companies that devise Cryptoeconomics as a strategic tool for BMI and, finally, (ii) we unfold the market practices associated with the market shaping process enacted by multiple case studies, including how these practices are interlinked as socio-material phenomena in the light of BMI constructs.
On states of quantum theory
Authors: Arab Amir R.
Published: July 2022

In this paper, the generalized quantum states, i.e. positive and normalized linear functionals on [Formula: see text]-algebras, are studied. First, we study normal states, i.e. states which are represented by density operators, and singular states, i.e. states cannot be represented by density operators. It is given an approach to the resolution of bounded linear functionals into quantum states by applying the Gelfand–Neumark–Segal (GNS) construction, i.e. the fundamental result of Gelfand, Neumark and Segal on the representation theory of [Formula: see text]-algebras, and theory of projections. Second, it is given an application in quantum information theory. We study covariant cloners, i.e. quantum channels in the Heisenberg and the Schrödinger pictures which are covariant by shifting, and it is shown that the optimal cloners cannot have a singular component. Finally, we discuss on the representation of pure states in the sense of the Gelfand–Pettis integral. We also give physical interpretations and examples in different sections of this work.
Charged anisotropic decoupled compact objects in f(R) gravity
Authors: Sharif M. , Aslam Mariyah
Published: July 2022

In this paper, we aim to formulate anisotropic solutions that represent charged self-gravitating static spheres in [Formula: see text] gravity. We introduce the effects of anisotropy in the domain of an isotropic solution by including an extra matter source. The spherical configuration is deformed by transforming radial as well as temporal metric functions. As a result of these transformations, the isotropic and anisotropic matter sources can be decoupled from each other. The system of field equations is disintegrated into two arrays such that the first set corresponds to the isotropic source while the second comprises the new gravitational source. The charged Krori–Barua spacetime is employed to specify the first set in the background of [Formula: see text] Starobinsky model. Two solutions of the other system are determined by incorporating a barotropic equation of state along with additional constraints on the anisotropic source. The matching conditions are imposed at the hypersurface to determine the values of unknown constants. Different features of the constructed models are inspected by using the mass and radius of Her X-I. One of the constructed solutions agrees with the viability and stability conditions for specific values of charge and the decoupling parameter.
Predicting Students Drop-out in MOOC from Learning Behavior Using Machine Learning
Authors: ALJ Zakaria , Malki Mohammed Ouçamah Cherkaoui
Published: July 2022

In this paper, we investigate how to predict student drop-out using machine-learning approaches. We discuss three methods: logistic regression, random forest and gradient boosting (GB). We used the KDD cup 2015 dataset. Since our dataset is unbalanced, a sampling technique called synthetic minority over-sampling technique (SMOTE) was used. Six models are then obtained, for each model we used a grid search cross-validation to find which are the parameters that optimize the mapping function according to the accuracy and the area under the receiver operating characteristic (AUC ROC) score. In order to validate our scores, we used the 10-fold cross-validation technique. Our findings show that ensemble machine-learning methods produce better results than basic machine-learning methods. The obtained results have proved that the extracted features and the used techniques are able to predict the drop-out with high efficiency. These relevant models were used with autoregressive moving average (ARIMA) model for time series data to detect the student at high risk of drop-out in earlier weeks of the course. The obtained AUC ROC for KDD Cup dataset with GB reaches 0.89 which is 0.1 close to the KDD cup winner.
Enhanced Spin Transfer Torque in Single Barrier Model Tunnel Junctions Containing Disordered Interface
Authors: Harikumar Parvathy , Chandra Sharat
Published: July 2022

We investigate the role of magnetic impurities in the barrier region in enhancing the torque transferred to the free ferromagnet layer in a non-collinear model tunnel junction. The tunnel junction is modeled using the non-equilibrium Green’s function formalism within the tight-binding approximation. The position of the impurity which is described by the single impurity Anderson model is found to have a profound impact on the trends observed in the spin transfer torque. The parallel ([Formula: see text]) torque is observed to have a switch on-off step-like bias behavior while the perpendicular ([Formula: see text]) torque exhibits a change in sign between the switch-on bias voltages. The spin transfer torque is found to be dramatically enhanced when the impurity is positioned at the interface of a five-layer barrier which is three orders of magnitude larger even at temperatures as high as 200[Formula: see text]K. With this formulation the effect of Coulomb repulsion at the impurity site on the torque could be deduced and the obtained results are explained in terms of the region-wise electronic density of states in the junction.
Compensation and Critical Behavior of Mixed Spin Ising Model with Four-Spin Interactions in a Crystal Field
Authors: Farsal D. , Bennai M.
Published: July 2022

We study the thermodynamical properties of two-dimensional mixed spin Ising system consisting of spin-[Formula: see text] and spin-1 with four-spin interactions in crystal field interactions on a square lattice within the framework of the finite cluster approximation based on single-site cluster theory. In this paper, the phase diagrams show qualitatively and quantitatively interesting features. In fact, the system exhibits a variety of interesting features resulting from the introduction of the four-spin interactions and the crystal field interactions. Finally, using the same method, we study the behavior of the total magnetization of the Ising model with four-spin interactions in the crystal field to show the existence of compensation points and point intervals for certain values of [Formula: see text].
SARS-CoV-2 Is Not Special, but the Pandemic Is: The Ecology, Evolution, Policy, and Future of the Deadliest Pandemic in Living Memory
Authors: Brinkworth Jessica F. , Rusen Rachel M.
Published: July 2022

The COVID-19 pandemic is extraordinary, but many ordinary events have contributed to its becoming and persistence. Here, we argue that the emergence of the severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) virus, which has radically altered day-to-day life for people across the globe, was an inevitability of contemporary human ecology, presaged by spillovers past. We show the ways in which the emergence of this virus reiterates other infectious disease crises, from its origin via habitat encroachment and animal use by humans to its evolution of troublesome features, and we spotlight a long-running crisis of inequitable infectious disease incidence and death. We conclude by describing aspects of SARS-CoV-2 and the COVID-19 pandemic that present opportunities for disease control: spaces for intervention in infection and recovery that reduce transmission and impact. There are no more “before times”; therefore, we encourage embracing a future using old mitigation tactics and government support for ongoing disease control.