Universal optimal hole-doping concentration in single-layer high-temperature cuprate superconductors

We argue that in cuprate physics there are two types, hole content per CuO$_2$ plane ($P_{pl}$) and the corresponding hole content per unit volume ($P_{3D}$), of hole-doping concentrations for addressing physical properties that are two-dimensional (2D) and three-dimensional (3D) in nature, respectively. We find that superconducting transition temperature ($T_c$) varies systematically with $P_{3D}$ as a superconducting \textquotedblleft $dome$\textquotedblright with a universal optimal hole-doping concentration $P_{3D}^{opt.}$ = 1.6 $\times$ 10$^{21}$ cm$^{-3}$ for single-layer high temperature superconductors. We suggest that $P_{3D}^{opt.}$ determines the upper bound of the electronic energy of underdoped single-layer high-$T_c$ cuprates.Comment: 8 pages, 4 figures; added references ;accepted for the publication in Supercond. Sci. Technol ; Ref. 13 is revise

A convertor and user interface to import CAD files into worldtoolkit virtual reality systems

Virtual Reality (VR) is a rapidly developing human-to-computer interface technology. VR can be considered as a three-dimensional computer-generated Virtual World (VW) which can sense particular aspects of a user's behavior, allow the user to manipulate the objects interactively, and render the VW at real-time accordingly. The user is totally immersed in the virtual world and feel the sense of transforming into that VW. NASA/MSFC Computer Application Virtual Environments (CAVE) has been developing the space-related VR applications since 1990. The VR systems in CAVE lab are based on VPL RB2 system which consists of a VPL RB2 control tower, an LX eyephone, an Isotrak polhemus sensor, two Fastrak polhemus sensors, a folk of Bird sensor, and two VPL DG2 DataGloves. A dynamics animator called Body Electric from VPL is used as the control system to interface with all the input/output devices and to provide the network communications as well as VR programming environment. The RB2 Swivel 3D is used as the modelling program to construct the VW's. A severe limitation of the VPL VR system is the use of RB2 Swivel 3D, which restricts the files to a maximum of 1020 objects and doesn't have the advanced graphics texture mapping. The other limitation is that the VPL VR system is a turn-key system which does not provide the flexibility for user to add new sensors and C language interface. Recently, NASA/MSFC CAVE lab provides VR systems built on Sense8 WorldToolKit (WTK) which is a C library for creating VR development environments. WTK provides device drivers for most of the sensors and eyephones available on the VR market. WTK accepts several CAD file formats, such as Sense8 Neutral File Format, AutoCAD DXF and 3D Studio file format, Wave Front OBJ file format, VideoScape GEO file format, Intergraph EMS stereolithographics and CATIA Stereolithographics STL file formats. WTK functions are object-oriented in their naming convention, are grouped into classes, and provide easy C language interface. Using a CAD or modelling program to build a VW for WTK VR applications, we typically construct the stationary universe with all the geometric objects except the dynamic objects, and create each dynamic object in an individual file

Etymology-based instructional system: using hypermedia to teach the recognition of Chinese characters to beginning learners of Chinese as a second language

As a logographic script, written Chinese conveys meaning directly from its graphic forms. Numerous researchers have suggested the pedagogical strategy of teaching Chinese writing by emphasizing the pictorial features of Chinese characters. This study was conducted to develop and to evaluate an instructional system in which instructional materials are based upon Chinese etymology and presented by hypermedia system;Thirty characters were selected, and pertinent information such as original forms, evolution of shapes, meanings, pronunciations,and applications were included. Presentation of the material, stored on a videodisc, was controlled by a HyperCard program;Twenty-eight beginning learner of Chinese as a second language in Taiwan, Republic of China, participated in the study as subjects; seven Chinese-language/literature instructors volunteered to evaluate the system. The relations of subjects\u27 linguistic backgrounds and attitudes towards the system, as well as their interests in learning Chinese characters before and after using the system, were investigated;Two significant results were found. Native speakers of alphabetic languages showed significantly more positive attitudes towards computer use than did native speakers of syllabic languages. Subjects\u27 interest in learning Chinese characters after using the system was significantly greater than was their interest before. But relations between attitude towards the system and a number of linguistic variables, with the exception of the native-language variable, were not significant;Verbal comments from subjects and Chinese language/literature instructors indicated the program\u27s emphasis on pictorial features and etymological analyses of Chinese characters was quite valuable in instruction of the Chinese writing system

Choose Your Words Carefully: Reimagining Retaliatory Arrest After \u3ci\u3eNieves v. Bartlett\u3c/i\u3e

In the summer of 2020, the United States experienced potentially its largest ever social movement in the protests against racial inequality. Predictably, protestors clashed with law enforcement officers, often leading to arrests. Arrested individuals could bring § 1983 retaliatory arrest claims alleging that the officers deprived them of their First Amendment right to free speech. Such claims underline the tension between two vital interests: free speech and law enforcement effectiveness. In 2019, the U.S. Supreme Court decided Nieves v. Bartlett, which crafted a new framework for retaliatory arrest claims that consequently diminished a plaintiff’s chance to prevail and recover damages. The Court held that, aside from a narrow exception, the presence of probable cause would extinguish the plaintiff’s claim. Rather than striking a balance between the two interests, the Court heavily tipped the scale in favor of law enforcement. Challenging the Court’s current position, this Note examines prior § 1983 retaliation decisions and concludes that a more appropriate framework would eradicate the probable cause standard and instead permit introduction of evidence of an officer’s subjective mindset. Further, to overcome the causal complexity inherent in retaliatory arrest claims, this Note advocates for the addition of a proximate cause requirement, such that the interests of both parties can be adequately balanced. Ultimately, this new framework provides the opportunity for both the plaintiff and the law enforcement officer to litigate about the officer’s subjective motivation surrounding the arrest

FUNCTIONALIZATION AND CHARACTERIZATION OF MULTI-WALLED CARBON NANOTUBES/POLYPROPYLENE NANOCOMPOSITE

Chemical and physical functionalization of multi-walled carbon nanotubes (MWCNT) have been commonly practiced to achieve better dispersion of carbon nanotubes in polymer matrix. However, not much is known about the effect of each functionalization method as well as a combination of both on the mechanical properties of carbon nanotubes/polypropylene nanocomposites. This work describes the various functionalization methods (acid-treatment, non-ionic surfactant treatment with Triton X-100), fabrication of MWCNT/PP nanocomposites via melt blending and injection molding as well as characterization of mechanical properties. Microscopy analysis (FESEM, TEM, XPS) showed effective purification of MWCNTs under acid treatment, and better dispersion under both chemical and physical functionalization techniques combined, in their respective. order. Tensile tests showed increase in tensile strength for the nanocomposites that contain MWCNTs up to 2 wt%. A decrease in tensile strength was seen in samples that contain 4wt% ofMWCNTs for both raw and Triton X-100 functionalized, signifying MWCNT degradation/rebundling at composition with higher content. of MWCNTs. For the acid-treated MWCNTs, however, showed slight improvement even at 4wt%, showing a possibility of effective dispersion ofMWCNTs

The Cognitive Diagnostic Assessment Of The Learning Of Algebraic Expressions For Form Two Students

Pentaksiran diagnostik kognitif (PDK) berkemampuan untuk mentafsir kekuatan dan kelemahan dalam pembelajaran di samping memberi panduan untuk mengenalpasti ruang yang berpotensi untuk tujuan intervensi bagi pelajar yang menghadapi kesulitan dalam pembelajaran. Cognitive diagnostic assessment (CDA) has the capacity to assess students’ cognitive strengths and weaknesses in learning and serves guidance to identify potential areas of intervention for students struggling in learning

Storage of Cocoa (Theobroma Cacao L.) Seeds and Changes Associated With Their Deterioration

Cocoa (Theobroma cacao L .) seeds are recalcitrant and rapidly lose their viability during preparation and within two to three weeks of storage. To improve their storability, the responses of a cultivar of cocoa seeds (NA 33) to different drying methods and storage factors including seed moisture, storage temperature and fungi were investigated. Physiological, biochemical and structural changes associated with seed death caused by dehydration in the air-conditioned room (22oC, 55% RH) and chilling at 100C were also monitored