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Physical Unclonable Function (PUF) is a lightweight hardware security primitive and suitable for device authentication in the Internet of Things. However, each strong PUF instance must store at least 106 reliable challenge-response pairs in the center nodes, which brings an excessive storage overhead since centers connect massive remote PUFs. In this brief, an obfuscation-feedback-shift-register (OFSR) PUF is designed, consisting of certain weak PUF cells working with an obfuscation mechanism. Meanwhile, it efficiently reduces the storage overhead and overcomes the collapse response caused by normal linear-feedback-shift-register, providing higher security. Experiments show OFSR PUF has ideal performance on reliability, uniqueness, uniformity, randomness, and good resistance to machine learning attacks. [ABSTRACT FROM AUTHOR]

In recent years, micro-nano device characteristics like ferroelectrics and resistive switching are being used to build important security primitives such as Physical Unclonable Function (PUF). The micro-nano device-based hardware security primitives, although with higher security, energy efficiency, and integration density, suffer from serious reliability issues caused by process scaling. To mitigate this issue, this paper introduces a reconfigurable weak PUF based on spin-transfer torque magnetoresistive random-access memory (STT-MRAM), which adopts the crossing switches implemented with simple demultiplexes (DEMUXs) to improve the flexibility and reliability. Moreover, two algorithms, neighboring bit lines and top- $n$ n , are proposed to enlarge the gap between two parallel reading currents, thus further enhancing the reliability of PUF responses. Experimental results demonstrate that the proposed PUF scheme achieves good uniqueness (50.64 percent), uniformity (50.02 percent), and bit-aliasing ($\approx$ ≈ 49.80%). Particularly, the proposed method significantly improves the PUF reliability, achieving low bit error rate (BER $\leq$ ≤ 2.13%) within the range of -20 $^\circ$ ∘ C to 90 $^\circ$ ∘ C. [ABSTRACT FROM AUTHOR]

Trichoderma longibrachiatum MD33, a sesquiterpene alkaloid-producing endophyte isolated from Dendrobium nobile , shows potential medical and industrial applications. To understand the molecular mechanisms of sesquiterpene alkaloids production, a comparative transcriptome analysis was performed on strain MD33 and its positive mutant UN32, which was created using Ultraviolet (UV) mutagenesis and nitrogen ion (N+) implantation. The alkaloid production of UN32 was 2.62 times more than that of MD33. One thousand twenty-four differentially expressed genes (DEGs), including 519 up-regulated and 505 down-regulated genes, were identified. Gene Ontology (GO) and Kyoto Encyclopedia of Genes and Genomes (KEGG) pathway analysis revealed 139 GO terms and 87 biosynthesis pathways. Dendrobine, arguably the main sesquiterpene alkaloid the strain MD33 produced, might start synthesis through the mevalonate (MVA) pathway. Several MVA pathway enzyme-coding genes (hydroxy-methylglutaryl-CoA synthase, mevalonate kinase, and farnesyl diphosphate synthase) were found to be differentially expressed, suggesting that physical mutagenesis can disrupt genome integrity and gene expression. Some backbone post-modification enzymes and transcript factors were either discovered, suggesting the sesquiterpene alkaloid metabolism in T. longibrachiatum is a complex genetic network. Our findings help to shed light on the underlying molecular regulatory mechanism of sesquiterpene alkaloids production in T. longibrachiatum. [ABSTRACT FROM AUTHOR]

Lepton scattering is an established ideal tool for studying inner structure of small particles such as nucleons as well as nuclei. As a future high energy nuclear physics project, an Electron-ion collider in China (EicC) has been proposed. It will be constructed based on an upgraded heavy-ion accelerator, High Intensity heavy-ion Accelerator Facility (HIAF) which is currently under construction, together with a new electron ring. The proposed collider will provide highly polarized electrons (with a polarization of ∼80%) and protons (with a polarization of ∼70%) with variable center of mass energies from 15 to 20 GeV and the luminosity of (2–3) × 1033 cm−2 · s−1. Polarized deuterons and Helium-3, as well as unpolarized ion beams from Carbon to Uranium, will be also available at the EicC. The main foci of the EicC will be precision measurements of the structure of the nucleon in the sea quark region, including 3D tomography of nucleon; the partonic structure of nuclei and the parton interaction with the nuclear environment; the exotic states, especially those with heavy flavor quark contents. In addition, issues fundamental to understanding the origin of mass could be addressed by measurements of heavy quarkonia near-threshold production at the EicC. In order to achieve the above-mentioned physics goals, a hermetical detector system will be constructed with cutting-edge technologies. This document is the result of collective contributions and valuable inputs from experts across the globe. The EicC physics program complements the ongoing scientific programs at the Jefferson Laboratory and the future EIC project in the United States. The success of this project will also advance both nuclear and particle physics as well as accelerator and detector technology in China. [ABSTRACT FROM AUTHOR]

During heavy-ion experiments, the single-event gate rupture (SEGR) effects can still be observed in the vertical double-diffused power MOSFET (VDMOS) with radiation-hardened cells. Fault analysis demonstrates that the hot spots locate at the termination of the VDMOS. Then, several mitigation solutions for termination structure are discussed comprehensively by means of TCAD simulations. Finally, a combined hardness method with horizontally extending P+ region and adding floating N+ region is proposed. It is effective to reduce the electric field of gate oxide to below the calculated critical field, without additional masks and process steps. [ABSTRACT FROM AUTHOR]

In the harsh space environment, the phase-locked loop (PLL) circuit is vulnerable to radiation effects, which will lead to performance degradation or even function interrupts. In this article, a rad-hard low-noise PLL is designed with low power and area overhead and verified in a 130-nm silicon-on-insulator process. Heavy ion test demonstrates that the proposed PLL is immune to the single-event effect up to 83.7 MeV·cm2/mg. Furthermore, its single-event sensitivity is characterized and compared with an unhardened PLL by the pulsed laser test. Finally, the gamma-ray radiation experiment confirms that it can provide >300 krad(Si) total ionizing dose assurance. [ABSTRACT FROM AUTHOR]

To mitigate the total ionizing dose (TID) effects of the dual-direction silicon-controlled rectifier, based on laterally diffused metal–oxide–semiconductor (LDMOS-DDSCR), a common-centroid layout arrangement with multiple octagonal units is proposed and fabricated in an 18-V Bipolar-CMOS-DMOS process. The symmetrical characteristics of the bidirectional electrostatic discharge (ESD) protection are verified by transmission line pulse tests. Gamma-ray irradiation experiments demonstrate that the proposed device is tolerant of TID effects up to 100 krad(Si), whereas the traditional finger-type LDMOS-DDSCR loses its function at 50 krad(Si). Finally, the ESD performance is also characterized at high temperatures which confirms that the proposed device is an excellent candidate for space applications. [ABSTRACT FROM AUTHOR]

The reliability issues of integrated circuits are attracting more attention, especially in extreme environments like radiation and elevated temperature conditions. The impact of ionizing radiation and temperature effects on the electrostatic discharge (ESD) protection devices should not be negligible. In this paper, A low-voltage dual-direction silicon controlled rectifier (DDSCR) and a high-voltage DDSCR based on laterally diffused metal oxide semiconductor are chosen and fabricated in a 5 V/18 V Bipolar-CMOS-DMOS process. To study the combined effects of ESD and total-ionizing dose, transmission line pulse (TLP) measurements are conducted right after exposure to 60Co gamma-ray up to 200 krad(Si). Besides, the TLP tests are performed at different temperatures ranging from 300 to 400 K to show the impact of elevated temperature on ESD devices. In the meanwhile, the physical mechanisms of the synergistic effects are investigated by means of three-dimensional (3D) TCAD simulations. [ABSTRACT FROM AUTHOR]

Doping, which is the intentional introduction of impurities into a material, can improve the metal-semiconductor interface by reducing Schottky barrier width. Here, we present high-quality two-dimensional SnS2 nanosheets with well-controlled Sb doping concentration via direct vapor growth approach and following micromechanical cleavage process. X-ray photoelectron spectroscopy (XPS) measurement demonstrates that Sb contents of the doped samples are approximately 0.22%, 0.34% and 1.21%, respectively, and doping induces the upward shift of the Fermi level with respect to the pristine SnS2. Transmission electron microscopy (TEM) characterization exhibits that Sb-doped SnS2 nanosheets have a high-quality hexagonal symmetry structure and Sb element is uniformly distributed in the nanosheets. The phototransistors based on the Sb-doped SnS2 monolayers show n-type behavior with high mobility which is one order of magnitude higher than that of pristine SnS2 phototransistors. The photoresponsivity and external quantum efficiency (EQE) of Sb-SnS2 monolayers phototransistors are approximately three orders of magnitude higher than that of pristine SnS2 phototransistor. The results suggest that the method of reducing Shottky barrier width to achieve high mobility and photoresponsivity is effective, and Sb-doped SnS2 monolayer has significant potential in future nanoelectronic and optoelectronic applications. [ABSTRACT FROM AUTHOR]

Two-dimensional (2D) van der Waals (vdWs) metal-semiconductor heterostructures with atomically sharp interface and matched work functions have recently attracted great attention due to their unique electronic and optoelectronic properties. Here we report the vapor phase epitaxial growth of large-scale vertical Sb/WSe2 metal-semiconductor vdWs heterostructures with uniform stacking orientation. Compared with the growth on SiO2/Si substrate, the thickness of Sb nanosheet on WSe2 can be reduced effectively to monolayer. We construct Sb-WSe2-Au asymmetric electrodes photodiode based on the Sb/WSe2 heterostructures. Electrical transport measurements indicate that the photodiode show obvious rectifying effect. Optoelectronic characterizations show prominent photoresponse with a high photoresposivity of 364 mA/W, a fast response time of less than 8 ms, a large open-circuit voltage of 0.27 V and a maximum electrical power output of 0.11 nW. The direct growth of high-quality metal-semiconductor vdWs heterostructures may open up new realms in 2D functional electronics and optoelectronics. [ABSTRACT FROM AUTHOR]

Cultural diversity is a reality in contemporary American society. Cultural and ethnic differences have been frequently addressed sociologically, historically, and politically as a social problem or a source of social [...]

Reflecting on Shing-Ling Chen's experience of being a Leukemia child's mother encountering others' seemingly hurtful support of her misery, the authors address the ethics of having fun activities as fundraisers for victims of traumatic events. The authors question the adequacy of hosting entertaining activities to fundraise for victims of Asian Tsunami, or patients of amyotrophic lateral sclerosis (ALS; that is, the ALS ice-bucket challenge) and cancers (e.g., polar plunge), and so on. The social dynamics and communication processes involved in these events are analyzed. [ABSTRACT FROM AUTHOR]

Abstract: Recent development of donor–acceptor (D–A) structure copolymers has led to the remarkable enhancement of mobility over 10 cm2 (V s)−1 in organic semiconductors. Despite these achievements, a thorough understanding of the correlation between molecular structure and charge transport properties is still not achieved. With this goal in mind, the electrical properties of three copolymers based on the naphthalenediimide (NDI) acceptor with different donor units are compared, and the effect of increasing donor length on the electronic structure of semiconductors and the resulting charge transport performance is studied. Structural and morphological characterizations are done to reveal the macro transport properties of the semiconductor films. Then, electrical measurements of the field‐effect transistors at variable temperatures are carried out to probe the charge transport property of the semiconductor films. Overall, it is found that the increasing of the donor length from one to three thiophene units would reduce the energetic disorder in the semiconductor films. Meanwhile, the electron cloud overlap between acceptor units would be weakened, which is detrimental to electron transport. Thus, a trading‐off between energetic disorder and electron cloud overlap is critical for achieving high mobility in this NDI–based copolymer system. [ABSTRACT FROM AUTHOR]

The sensitivity of total-ionizing-dose (TID) response on a single-event hardened phase-locked loop (PLL) fabricated in a 130-nm silicon-on-insulator process is investigated. Based on the study of device parameter degradation under radiation exposure, the changes of dc and RF performance of the PLL have been presented. TID experiments on the PLL show that the power-down current increases by 1.5 times, and the tuning range drops by 11.5%. At 600 MHz and up to 500 krad(Si), the integrated phase noise increases by 29.2%, and the reference spur increases by 3.4 dB. Finally, the mechanism underlying impact of TID on the phase noise and reference spur has been discussed comprehensively, which combined measured observations with circuit modeling and simulations. [ABSTRACT FROM AUTHOR]

Contact resistance effect is a major issue in organic field-effect transistors (OFETs) because it can severely limit or even dominate the overall performance of OFETs. This is especially true for recently developed high-mobility OFETs. Here, we present a systematic study of the contact resistance and its effect on mobility in high-mobility 2,7-dioctyl[1]benzothieno[3,2-b][1]benzothiophene (C8-BTBT) OFETs by scanning Kelvin probe microscopy. We find that the contact resistance effect can lower the mobility by a factor of four at some temperatures. More interestingly, it is seen that the contact resistance has significant influence on the temperature dependent mobility behavior. The contact resistance-corrected mobility demonstrates stronger band-like transport than the uncorrected mobility in the same temperature range, which has not been reported before. [ABSTRACT FROM PUBLISHER]

A radiation-hardened low-jitter phase-locked loop (PLL) with a low-mismatch charge pump and a robust voltage-controlled oscillator is designed in a 130 nm PD-SOI process. In order to evaluate the overall response to single-event effects, the accumulated phase jitter has been put forward, which can exclude the inherent noise floor and accumulate all the radiation-induced noise. Then the single-event sensitivity of the proposed PLL is comprehensively analyzed by heavy ion and pulsed laser tests. [ABSTRACT FROM PUBLISHER]

In this paper, a radiation-tolerant phase-locked loop (PLL) is designed and fabricated with 130 nm PD-SOI technology. A current-based charge pump is hardened using a current compensation technique in combination with the differential charge cancellation (DCC) layout of the complementary switches. Besides, the stacked SOI transistors are employed to mitigate single-event effects of the voltage-controlled oscillator. The experimental results show that the proposed PLL has no significant jitter variations under heavy-ion experiments, compared with TMR-hardened PLL. Besides, pulsed-laser testing comprehensively characterizes the single-event transients of the PLL and demonstrates its radiation tolerant performance. [ABSTRACT FROM PUBLISHER]

Existing studies demonstrate that the identity formation of internationally adopted children and the adjustments of adoptive families reside in the processes of cross-cultural and intercultural communication. However, there have been few studies on international adoption from the perspectives of intercultural and cross-cultural communication. Following a previous qualitative study on the experiences of adult international adoptees, this project employs a quantitative method to examine the ongoing (before, during, and after adoption) cross-cultural adaptation and identity formation of international adoptees from the perspectives of adoptive parents. The findings of the study have identified the key issues involved in the cross-cultural adaptation process and discussed experiences of adoptive families for dealing with those issues. [ABSTRACT FROM PUBLISHER]

Contact resistance is a common issue in organic field-effect transistors (OFETs). Although it is well known that both the contact resistance ( RC ) and channel resistance ( R {Ch} ) are generally gate-dependent, i.e., the resistance values are reduced by increasing gate voltages, the comparison of the gate dependence of RC and R {Ch} has rarely been reported. In this letter, we used scanning Kelvin probe microscopy to experimentally measure and compare the gate dependence of the two resistances. The results provide valuable information regarding the charge injection/extraction physics in OFETs. Moreover, the correlation between the gate dependence of the two resistances and the charge transfer characteristic of OFETs was investigated, which can give us some clues to the understanding of the non-ideal transfer curves (“kink” feature) observed in high-mobility OFETs, an issue that has caused both great interest and concern in the community. [ABSTRACT FROM PUBLISHER]

A surface-potential-based model is developed for the symmetric long-channel junctionless double-gate MOSFET. The relationships between surface potential and gate voltage are derived from some effective approximations to Poisson's equation for deep depletion, partial depletion, and accumulation conditions. Then, the Pao–Sah integral is carried out to obtain the drain current. It is shown that the model is in good agreement with numerical simulations from subthreshold to saturation region. Finally, we discuss the strengths and limitations (i.e., threshold voltage shifts) of the JLFET, which has been recently proposed as a promising candidate for the JFET. [ABSTRACT FROM AUTHOR]

The increasing multicultural diversity and changing cultural landscape in U.S. higher education call for a paradigmatic shift in the understanding and practice of teaching evaluation with regard to instructional and intercultural communication. This article examines the current evaluation instruments that privilege Western cultural values and tradition, re-conceptualizes the major definitions in the mainstream models, and presents the rationale and suggestions for developing an "intercultural instrument." Incorporating global perspectives in assessment of teaching and learning is a vital component in the education of global citizens in a multicultural society. [ABSTRACT FROM AUTHOR]

Explores teacher-student relationships in college education. Examination of organizational cultures in the classroom; Concepts on instructors' concern for students; Propositions on teaching as a mode of friendship.

In this study, tantalum coatings are deposited by a plasma spraying method aiming at enhancing the biocompatibility of the titanium implant. Tantalum oxide coatings are gained through the thermal oxidation of tantalum coatings at different temperatures for photothermal therapy. The effect of thermal oxidation on the morphology, composition, and structure of tantalum coatings has been studied. The UV–VIS–NIR spectra results, cancer therapy effect in vitro, and photothermal conversion properties among the tantalum oxide coatings under varied thermal treatment conditions are compared comprehensively. It has been proven that the tantalum coating treated at 200 °C exhibits the most intense NIR adsorption, the highest photothermal conversion effect, and the most excellent photothermal ablation effect in vitro. The results reveal that incomplete oxidation at a low temperature leads to the formation of oxygen vacancies, which narrow the band gap; this promotes its photothermal conversion ability. [ABSTRACT FROM AUTHOR]

Responsitivity is an important figure of merit for photodetectors. Here we demonstrated a simple yet efficient way to enhance the responsitivity of methylammonium lead iodide (MAPbI 3)-based photodetectors by utilizing organic semiconductors (OSCs) to form MAPbI 3 /OSC bilayer structures. These bilayer photodetectors are fabricated with a facile and low-cost spin-coating method, yet the responsitivity can be more than one order of magnitude higher than that of pristine MAPbI 3 photodetectors. More importantly, the physics behind the enhancement of responsitivity was analyzed and revealed by inspecting the physical processes in terms of light absorption, exciton dissociation and charge transport. The results indicate that the responsitivity enhancement is mainly attributable to the more efficient exciton dissociation and hole transport processes in the bilayer photodetectors. Image 1 • In this work, we demonstated that the responsitivity of organic-inorganic hybrid lead halide perovskites (MAPbI 3) based photodetectors can be dramatically enhanced by forming MAPbI 3 /organic semiconductor (OSC) bilayer films, and the physics behind the responsitivity enhancement was clarified. • Considering that there are so many organic semiconductors with different optical and electrical properties, it may open up opportunities to explore different combinations of perovskites and organic semiconductors for achieving high-performance photodetectors, or finely tune the performance of photodetectors according to our needs. • This work thus can be important to the development of application of pervoskite/OSC bilayer photodectors. [ABSTRACT FROM AUTHOR]