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A numerical method for solving singularly perturbed delay differential equations with a layer or oscillatory behavior for which a small shift is introduced in the reaction term is presented. The stability and convergence of the method have been investigated. To demonstrate the efficiency of the method, two model examples have been presented. Numerical results obtained by the present scheme described that the finding of the present method is accurate than the findings of the previous studies.

The first-principle calculation was used to understand new insight of Ca element refining grain structure in commercial purity Mg. Negative adsorption energy, strong ionic bond and negative shift o...

Invention disclosures are one measure of new scientific knowledge that represents and predicts the future scientific research output of a US federal laboratory. In this article, we document a negative shift in the production function for new scientific knowledge as measured by invention disclosures at one federal laboratory, the National Institute of Standards and Technology, over the first 16 years of the new millennium. We find a negative shift of the production function for new scientific knowledge, and that shift might reflect the coincidence of the information and communication technology revolution that enabled fast science, and the evaluation of research with uncritical use of citation counts that created incentives to focus on incremental research in crowded research topics.

We report the fabrication of P-doped α-Fe2O3 nanorod/BiVO4 heterojunction photoelectrode for photoelectrochemical (PEC) water splitting. The heterojunction photoelectrode is fabricated by combining methods of hydrothermal deposition, wet impregnation and metal organic decomposition. The structure and PEC activity of the photoelectrode are systemically studied. This heterojunction photoelectrode exhibits a surprising photocurrent density of 1.17 mA/cm2 at 0.8 V vs. Ag/AgCl, which is approximately 3.55 times higher than that of the pristine α-Fe2O3. The photoconversion efficiency is 9.58 times higher than α-Fe2O3 and the onset potential has an obvious negative shift of 450 mV compared to the α-Fe2O3 for the heterojunction photoelectrode. The significant enhancement of PEC water splitting performance is attributed to the heterojunction structure and the synergistic effects of P-doping, which contributes to expediting electron and hole transfer and reducing carriers recombination. This novel design may provide an efficient way to developing efficient heterojunction photoelectrodes for practical PEC application.

Signed shifts are generalizations of the shift map in which, interpreted as a map from the unit interval to itself sending x to the fractional part of Nx, some slopes are allowed to be negative. Permutations realized by the relative order of the elements in the orbits of these maps have been studied recently by Amigo, Archer and Elizalde. In this paper, we give a complete characterization of the permutations (also called patterns) realized by signed shifts. In the case of the negative shift, which is the signed shift having only negative slopes, we use the characterization to give an exact enumeration of these patterns. Finally, we improve the best known bounds for the number of patterns realized by the tent map, and calculate the topological entropy of signed shifts using these combinatorial methods., Comment: 35 pages. Theorem 3.6 generalizes Theorem 2.7 in arXiv:1512.04479, by the authors, using a similar argument

The association between carbon emissions and international trade has been examined thoroughly; however, consumption-based carbon emissions, which is adjusted for international trade, have not been studied extensively. Therefore, the present study assesses the asymmetric impact of trade (import and export) and economic growth in consumption-based carbon emissions (CCO2) using the MINT nations (Mexico, Indonesia, Nigeria and Turkey) as a case study. We applied the Nonlinear ARDL to assess this connection using dataset between 1990 and 2018. The outcomes from the BDS test affirmed the use of nonlinear techniques. Furthermore, the NARDL bounds test confirmed long-run association between CCO2 and exports, imports and economic growth. The outcomes from the NARDL long and short-run estimates disclosed that positive (negative) shocks in imports increase (decrease) CCO2 emissions in all the MINT nations. Moreover, positive (negative) shocks in exports decrease (increase) CCO2 emissions in all the MINT nations. As expected, a positive shock in economic growth triggers CCO2 emissions while a negative shift does not have significant impact on CCO2 emissions in the MINT nations. Furthermore, we applied the Gradual shift causality test and the outcomes disclose that imports and economic growth can predict CCO2 emissions in the MINT nations. The study outcomes have significant policy recommendations for policymakers in the MINT nations.

One of the impacts of COVID-19 has been a negative shift in public opinion towards residential and care home settings. Adrian Ashurst discusses the importance of implementing an excellent marketing plan during these difficult times.

Emerging markets and volatility spillover effects remained a highly focused area in the field of financial economics. Therefore, we have empirically testified the volatility spillover effects between markets of emerging economies i.e Pakistan, China, Bangladesh, and India during the period from 1st January 2000 to 31st December 2015. We used Multivariate GARCH and causality models to identify the spillover effects. It is concluded that there exists significant evidence of spillover effect from the market of Pakistan to India, India to China and from China to Pakistan. However, the larger negative shift in the volatility occurs more frequently than positive shocks. Hence it is concluded that the impact of own spillovers of the markets is much higher than the impact of cross-market spillovers during this period.

The withstand capability and threshold voltage ( $V_{\mathrm {TH}}$ ) instability of 1.2-kV silicon carbide (SiC) MOSFETs under repetitive short circuit (SC) tests are investigated. An SC test system is constructed to apply repetitive SC stress to SiC MOSFETs and measure the transfer $I$ – $V$ characteristics and gate-to-source leakage current ( $I_{\mathrm {GSS}}$ ) after each set of SC tests. To evaluate the SC capability, repetitive SC tests with different SC durations ( $t_{p}$ ) are conducted until device failure. The SC withstand time (SCWT) at 1000 SC cycles is found to be $\sim 3.3~\mu \text{s}$ . $V_{\mathrm {TH}}$ instability under repetitive SC tests prior to the device failure is characterized. A bidirectional $V_{\mathrm {TH}}$ shift behavior, i.e., negative shift at shorter $t_{p}$ and positive shift at longer $t_{p}$ , was revealed. The $V_{\mathrm {TH}}$ shifts under repetitive SC tests are attributed to the SC pulse process according to the results of high-temperature reverse bias (HTRB) and dynamic high-temperature gate bias (HTGB) tests. The underlying mechanisms of the complex $V_{\mathrm {TH}}$ shift behavior are explained in a unified framework by taking into account the junction temperature ( $T_{j}$ ) increase with longer $t_{p}$ . TCAD device simulation is used to help analyze the mechanisms.

We take a new look on the Fama and French (1993) three-factor asset pricing model by extracting risk premium contributions for each factor based on solving a system of linear equations. The risk premium contributions become uncorrelated with the underlying factor excess returns and capture the isolated compensation of a given risk factor. We show that the risk premium contributions feature a January-seasonality, which exhibits a negative shift after the year 1993. Furthermore we find that after 1993 the risk premium contributions of the SMB and HML factor are strongly related to sentiment and predictable by dividend yield.

The geometric structure of 38-atom AgPd and AgCu nanoalloys is obtained by the genetic algorithm and density functional theory for all compositions and their surface phase stability diagrams are established to provide a clear image for the initial oxidation process. Ag surface segregation is confirmed for both AgPd and AgCu nanoalloys in vacuum. Pure Pd and Cu nanoparticles have lower surface phase stability than bulk metals to be oxidized and the alloying can improve the oxidation resistance. Segregated AgCu nanoalloys have higher phase stability than mixed AgCu in vacuum and have lower surface phase stability than mixed AgCu nanoalloys in an oxygen atmosphere. Unexpectedly, segregated AgPd nanoalloys have both higher phase stability in vacuum and higher surface phase stability in an oxygen atmosphere than that of mixed AgPd nanoalloys. The higher surface phase stability of segregated AgPd nanoalloy could be attributed to the slight elevation of Pd Milliken charge and negative shift of d-band center. Compared with the selective oxidation in conventional alloy oxidation models where the selective oxidation is related to alloy composition, the nanoalloy oxidation is proposed to correlate with surface segregation in AgPd and AgCu nanoalloys in this work, which promotes the development of the conventional alloy oxidation models in that the surface segregation is a precursor to the surface oxidation of nanoalloy and plays a critical role in the selective oxidation of nanoalloy.

LaAlGe and PrAlGe are members of the RAlGe series of compounds (with R a light rare-earth element), which have been shown to host Weyl fermions. By exchanging the rare-earth cation, RAlGe offers a remarkable tunability of its electronic properties thereby allowing to identify the electronic response of Weyl semimetals under varying temperature- and magnetic-field conditions. Through a comparative Al27 NMR study of LaAlGe and PrAlGe, we show that the rare-earth element can also be used to tune the NMR response of Weyl fermions in the host. In both cases, we observe unusual NMR shifts that deviate significantly from those in ordinary metals, such as Al. In LaAlGe, we report the observation of a small negative shift, strongly varying with temperature, which can be explained by a recent theory of NMR shifts invoking Weyl fermions. In PrAlGe, instead, we report a giant positive NMR shift of up to 20% at 6 K, most likely due to the transferred hyperfine field from the Pr3+4f-electron local moments. We discuss the implications of our findings on future studies of Weyl-fermion systems. © 2020 American Physical Society. ISSN:1098-0121 ISSN:0163-1829 ISSN:1550-235X ISSN:0556-2805 ISSN:2469-9969 ISSN:1095-3795 ISSN:2469-9950

This study examined the association between smart device usage and the 1-year change in refractive error among a representative sample of Hong Kong children and adolescents aged 8&ndash, 14 years. A total of 1597 participants (49.9% male, mean age 10.9, SD 2.0) who completed both baseline (2017&ndash, 2018) and 1-year follow-up (2018&ndash, 2019) eye examinations were included in the present study. The non-cycloplegic auto-refractive error was measured and the average spherical equivalent refraction (SER) was analyzed. The participants also self-reported their smart device usage at baseline. Multivariate regression adjusted for age, sex, baseline SER, parents&rsquo, short-sightedness, BMI, time spent on moderate-to-vigorous physical activity (MVPA), and caregiver-reported socio-economic status showed that, compared with the reference group (&lt, 2 hours per day on both smartphone and tablet usages), those who spent &ge, 2 hours per day using a smartphone and &lt, 2 hours per day using a tablet had a significantly negative shift in refractive error (1-year change in SER &minus, 0.25 vs. &minus, 0.09 D, p = 0.01) for the right eye, while the level of significance was marginal (1-year change &minus, 0.28 vs. &minus, 0.15 D, p = 0.055) for the left eye. To conclude, our data suggested spending at most 2 hours per day on both smartphones and tablets.

Room-temperature plasma treated graphene based FET was firstly proposed for the DNA hybridization detection. Affinity and electrical properties of the graphene based DNA-FET sensor were studied and improved benefits from the surface modification. The facile room-temperature Ar plasma easily removes residues from the graphene surface and changes the hydrophilic properties of graphene, which is important for our solution gated DNA-FET sensor. Limit of the detection of below 10 aM is obtained in our experiment. Especially, DNA concentration (CDNA)/the amount of net drain current (ΔI) and the negative shift in the VCNP value of the GFET sensor with the plasma treated 30 s are all improved compared with that without treatment. It shows that the easily plasma treatment of the graphene surface can be used for the solution gated FET sensor.

It is estimated that £5 billion are invested yearly into chronic wound management by the NHS. Whilst the demand for treatment rises every year, it has become harder to treat wounds given the burden of antimicrobial resistance. Chronic wounds can easily become harbouring grounds for polymicrobial biofilms in which species interact in specific ways. This study assessed the interactions between two commonly co-isolated chronic wound pathogens: Pseudomonas aeruginosa (ATCC 9027) and Staphylococcus aureus (EMRSA 15), whose biofilm relation initiates a Gram-negative shift. During this phenomenon, P. aeruginosa takes over the majority of the bacterial community, at the detriment of S. aureus. The Gram-negative shift marks the turning point from an acute to a chronic wound. The pH of a chronic wound is typically alkaline, and it was hypothesised that topical dressings with an acidic pH could disrupt the onset of the Gram negative shift, and therefore chronicity. Six different topical dressings with low pH were used in achronic wound model to assess their ability to reverse or delay the Gram-negative shift. It was found that they did not have an impact on the onset of the Gram-negative shift, despite their low pH values. However, the lower the pH of the dressings, the more frequently small colony variant (SCV) bacteria were observed in the biofilm. SCVs are known for causing persistent or chronic infections. It was therefore concluded that low pH dressings alone may not be favourable for managing chronic wound infection.

In this paper a stabilized central difference method is presented for the boundary value problem of singularly perturbed differential equations with a large negative shift. The central difference approximations for the derivatives are modified by re-approximating the error terms, leading to a stabilizing effect. The method is found to be second order convergent. Several numerical examples are solved to demonstrate the efficiency of the method.

The threshold voltage ( ${V} _{\text {TH}}$ ) instability of p-GaN/AlGaN/GaN HEMTs was investigated under forward gate stress. A unique bidirectional ${V} _{\text {TH}}$ shift ( $\Delta {V}_{\text {TH}}$ ) with the critical gate voltage ( ${V} _{\text {G}}$ ) of 6 V was observed. The carrier transport mechanisms underlying the $\Delta {V} _{\text {TH}}$ were extensively investigated through the voltage-dependent, time-resolved, and temperature-dependent gate current. The gate current is decomposed into electron and hole current in three distinct regions with respect to ${V} _{\text {G}}$ , which are off-state for ${V} _{\text {G}} V ( ${V} _{\text {TH}}$ ), on-state for $1.2~{V} V and “gate-injected” region for ${V} _{\text {G}}> {5}$ V. In off-state, the electrons were thermally activated and transport towards the gate, while electron-trapping governed by the space charge limited conduction (SCLC) in AlGaN barrier was observed in on-state and “gate-injected” region. Such an electron-trapping effect results in the positive ${V} _{\text {TH}}$ shift for ${V} _{\text {G}} V. Meanwhile, the marginal hole transport from gate by thermal activation was also captured by gate current, which features negligible impact on ${V} _{\text {TH}}$ . However, for ${V} _{\text {G}}> {6}$ V, a drastic hole injection triggered by high ${V} _{\text {G}}$ takes place that causes subsequent hole-trapping in AlGaN barrier and hole-injection into GaN buffer. The injected holes enhance the positive charge in the gate region and turned the positively shifted ${V} _{\text {TH}}$ into a negative shift.

The magnesium oxide modified TiO2 nanotube arrays (TiO2 NTs) was prepared to investigate the photoelectrochemical (PEC) cathodic protection performance to 304 stainless steel (SS 304). With the annealing treatment at different temperature, the surface of the modified materials changed remarkably. The film-like Mg(OH)2 obtained at 400 °C transformed to MgO particles after treatment at 500 °C and 600 °C. Further thermal processing at 700 °C enables MgTixOy@TiO2 shell-core structure. Using photoelectrochemical approaches to study the series samples, the cathodic protection performance of the modified TiO2 NTs has significantly improved. The magnesium oxides modified TiO2 NTs treated at 600 °C (Ti-Mg-O 600) shows the best PEC cathodic protection to the underneath steel. Further investigation shows that the highly enhanced PEC cathodic protection performance of Ti-Mg-O 600 was attributed to the effective separation of photogenerated carriers, the increase of carrier concentration and the negative shift of the conduction band potential.

A unified explanation is proposed to consistently explain the two-step degradation of amorphous InGaZnO (a-IGZO) thin film transistors (TFTs) under DC positive bias temperature instability (PBTI) stress without or with different drain stress voltages (Vds). For PBTI stress without stress Vds, this initial negative Vth shift is believed to be induced by donor-like defect states corresponding to H2O molecule and intrinsic defects, while for PBTI stress with stress Vds, the negative shift is believed to be induced by donor-like defect states corresponding to oxygen vacancies. The gate-bias-induced electron trapping mechanism is responsible for positive Vth shift. These transitions from negative to positive Vth shift are resulted from the competition between the donor-like states creation and electron trapping.

Low nitrogen isotopic compositions (δ15N) have been reported in deposits from the proto-North Atlantic and western Tethys during Oceanic Anoxic Event 2 (OAE2) at the Cenomanian-Turonian (C-T) transition. It has been proposed that the low δ15N values may have resulted from enhancement of N2 fixation and/or incomplete assimilation of the upwelled ammonium due to expansion of anoxic/euxinic conditions. However, few δ15N measurements are available for the sediments from the eastern Tethys and the Pacific and therefore the global significance of the N cycle and its environmental implications remains to be tested. Here, we present δ15N data from OAE2 deposits in the Gongzha section in the Tingri area of southern Tibet, which was located on the southern margin of the eastern Tethys during the mid-Cretaceous. The δ15N data reveal a large perturbation of the N cycle during OAE2. The pronounced negative shift in δ15N prior to OAE2, as well as the persistent low δ15N values during OAE2, imply the significant contribution of N2 fixation. The changes in the marine N cycle suggest that the expansion of an anoxic environment may also have occurred in the southern continental margin areas of eastern Tethys. The coincidence of the marine faunal turnover and the perturbation of the N cycle suggests that the expansion of anoxic water masses may have played an important role in the extinction of marine organisms across the C-T boundary in eastern Tethys.

ObjectivesTo explore women’s experiences of breastfeeding beyond infancy (>1 year). Understanding these experiences, including the motivators, enablers and barriers faced, may help inform future strategies to support and facilitate mothers to breastfeed for an optimal duration.DesignAn exploratory qualitative study using an interpretive approach. Nineteen semistructured interviews were conducted (in person, via phone or Skype), transcribed and thematically analysed using the framework method.SettingParticipants drawn from across the UK through online breastfeeding support groups.ParticipantsMaximum variation sample of women currently breastfeeding a child older than 1 year, or who had done so in the previous 5 years. Participants were included if over 18, able to speak English at conversational level and resident in the UK.ResultsThe findings offer insights into the challenges faced by women breastfeeding older children, including perceived social and cultural barriers. Three core themes were interpreted: (1) parenting philosophy; (2) breastfeeding beliefs; (3) transition from babyhood to toddlerhood. Women had not intended to breastfeed beyond infancy prior to delivery, but developed a ‘child-led’ approach to parenting and internalised strong beliefs that breastfeeding is the biological norm. Women perceived a negative shift in approval for continued breastfeeding as their child transitioned from ‘baby’ to ‘toddler’. This compelled woman to conceal breastfeeding and fostered a reluctance to seek advice from healthcare professionals. Mothers reported feeling pressured to breastfeed when their babies were young, but discouraged as children grew. They identified best with the term ‘natural-term breastfeeding’.ConclusionsThis study suggests that providing antenatal education regarding biological weaning ages and promotion of guidelines for optimum breastfeeding duration may encourage more women to breastfeed for longer. Promoting the concept of natural-term breastfeeding to mothers, and healthcare professionals, employers and the public is necessary to normalise and encourage acceptance of breastfeeding beyond infancy.

Spinel oxides have attracted widespread interest for electrocatalytic applications owing to their unique crystal structure and properties. The surface structure of spinel oxides significantly influences the electrocatalytic performance of spinel oxides. Herein, we report a Li reduction strategy that can quickly tune the surface structure of CoFe2O4 (CFO) nanoparticles and optimize its electrocatalytic oxygen evolution reaction (OER) performance. Results show that a large number of defective domains have been successfully introduced at the surface of CFO nanopowders after Li reduction treatment. The defective CFO nanoparticles demonstrate significantly improved electrocatalytic OER activity. The OER potential observed a negative shift from 1.605 to 1.513 V at 10 mA cm-2, whereas the Tafel slope is greatly decreased to 42.1 mV dec-1 after 4 wt % Li reduction treatment. This efficient Li reduction strategy can also be applied to engineer the surface defect structure of other material systems and broaden their applications.

Considering the recent shrinkage in Islamic banks’ profitability in Bangladesh, this study investigated whether these banks are less efficient than the conventional and mixed banks. Using 250 firm-year observations from 38 private commercial banks for the years from 2011 to 2017 and estimating operational efficiency through the Data Envelopment and Stochastic Frontier Analyses, we found robust evidence that Islamic banks are less efficient than the conventional and mixed banks. In additional analysis, it was found that the lower efficiency of Islamic banks was driven by their non-investment income. A significant negative shift in Islamic banks’ efficiency was evident in the most recent years compared to the earliest periods in our sample window. These findings helped us explain why the relative profitability of Islamic banks has declined recently. We suggest that Islamic banks’ management pay more attention to their portfolio of non-investment products and services in order to remain competitive in the fast-growing banking landscape in Bangladesh.

The crystal facet of the BiVO4 photoanode has potential influence on its charge-transfer and separation properties as well as water oxidation kinetics. In the present work, a BiVO4 polyhedral film with exposed {121}, {132}, {211}, and {251} high-index facets was synthesized by a facile Bi2O3 template-induced method and investigated as a photoanode for water oxidation. In comparison with the normal BiVO4 film with a {121} monohigh-index facet, the BiVO4 film with multihigh-index crystal facets shows higher activity and faster kinetics for photoelectrochemical water oxidation. Specifically, a higher photocurrent density of 1.21 mA/cm2 was achieved on the multihigh-index facet BiVO4 photoanode at 1.23 V versus reversible hydrogen electrode (RHE) in 0.1 M Na2SO4, which is about 200% improved over the normal BiVO4 photoanode (0.61 mA/cm2 at 1.23 V vs RHE). In addition, a negative shift of 300 mV onset potential for water oxidation was observed on the as-prepared BiVO4 photoanode (0.22 V vs RHE) relative to the...

Self-broadening and self-shift coefficients have been measured in the ν1 and ν3 bands of NH3 at room temperature for about 510 ro-vibrational lines with rotational quantum numbers 1 ≤ J ≤ 11. The measurements have been made in numerous branches located in the spectral range from 3050 to 3600 cm−1 using a high-resolution Fourier transform spectrometer. The data have been retrieved using a non-linear least squares multi-pressure fitting procedure of the first-order Rosenkranz profile to eight spectra of NH3. Analysis of the overlapped lines has allowed the measurement of line-mixing parameters for about 200 transitions. The results of pressure broadening coefficients obtained with and without accounting for line-mixing effect have been analyzed as a function of the branches. On average, the accuracies of self-broadening coefficients are estimated to be better than 4%. Those of self-shift and line-mixing are estimated to be about 11% and 17% respectively. About half of the lines have negative shift coefficients with numerous opposite signs for the symmetric and asymmetric doublet components. This work has also shown that line-mixing effects can contribute to the observed shift with a quadratic dependence in pressure. The whole set of results is given as supplementary material for use in spectroscopic databases.

Acarinina sibaiyaensis is a very distinctive and short-lived planktonic foraminiferal taxon that is restricted to the temporally short Carbon Isotope Excursion (CIE) interval characteristic of the Paleocene-Eocene Thermal Maximum (PETM) event. It is confined to the planktonic foraminiferal Zone E1 which in southern Egypt corresponds to the Dababiya Quarry Member (DQM). This member yields a complete record of the biotic changes induced by the intense warming during the basal Eocene . Although this distinctive taxon is widely distributed throughout the tropic to the temperate regions, its morphologic changes and phylogenetic relations during the CIE/PETM interval have not yet been documented. The present study discusses and documents the morphologic changes which affected the short-lived Ac. sibaiyaensis probably caused by the extreme warming during the very brief (175–200 ka) CIE/PETM interval in southern Egypt. These morphologic variations are particularly well developed in the middle phosphatic phase (Beds 2 and 3 of the DQM), in which the CIE curve shows its maximum negative shift. The origin, morphology, wall texture, coiling direction and their changes during ontogeny and evolution of Ac. sibaiyaensis during the CIE-PETM interval at Qreiya, Gebel Abu Had, northeast Qena (southern Nile Valley) and Darb Gaga (southeast of Kharga Oasis, southern Western Desert) are described, interpreted and illustrated. During the PETM, numerous intraspecific varieties of Ac. sibaiyaensis are recorded. Several evolutionary lineages are delineated; some of them stay within the morphologic range of Ac. sibaiyaensis, whereas others lead to other excursion taxa i.e. Acarinina africana and Morozovella allisonensis. In addition, forms transitional to taxa which appear in younger horizons than the PETM (younger than Zone E1) are recorded, described and illustrated.

In this study, we show that the difficulty of re-activating and retrieving the representations of potential referents from memory (retrieval difficulty) influences referential processing, and that this effect is independent of the number of potential referents for a pronoun or the probability of possible referential interpretations (referential coherence). In two experiments, we varied retrieval difficulty by manipulating whether two referential candidates were modified by extra semantic information or not, creating representationally rich (modified) or bare (unmodified) referential candidates, respectively, and we measured event-related brain potentials (ERPs) on following pronouns. We observed a sustained frontal negative shift (the Nref effect) on pronouns following bare, and therefore difficult-to-retrieve, referential candidates relative to those following representationally rich candidates, regardless of the ambiguity of pronouns and the probability of either referential interpretation. Since referential coherence was held constant across the conditions, the results suggest that retrieval difficulty affects referential processing independently of coherence. We discuss the implications for memory-based theories of language processing.

The irradiation and postirradiation annealing responses of SiC metal–oxide–semiconductor field-effect transistors (MOSFETs) are investigated under the application of different positive gate biases. During irradiation, the threshold voltage of the SiC MOSFETs showed a negative shift under the application of a positive gate bias. However, a significant reduction in this shift was observed as the positive gate bias increased from 20 to 24 V. The postirradiation annealing of the irradiated SiC MOSFETs was performed under various positive gate biases over the range from 32 to 44 V. A rapid reduction in the number of oxide-trapped charges was observed. These results indicate that the degradation of the threshold voltage in irradiated devices can be inhibited by the application of a higher gate voltage, while the high positive gate bias annealing represents an efficient way to recover the threshold voltage shift in these devices.

During the old poor law, many paupers had their possessions inventoried and later taken by authorities as part of the process of obtaining poor relief. Historians have known about this for decades, yet little research has been conducted to establish how widespread the system was, what types of parishioners had their belongings inventoried and why, what the legal status of the practice was, and how it affected social relations in the parish. Using nearly 450 pauper inventories, this article examines these historiographical lacunae. It is argued that the policy had no legal basis and came from local practices and policies. The system is found to be more common in the south and east of England than in the north, and it is argued that the practice gradually became less common from the late eighteenth century. The inventorying of paupers’ goods often formed one of the many creative ways in which parishes helped the poor before 1770, as it guaranteed many paupers assistance until death. However, by the late eighteenth century the appraising of paupers’ goods was closely tied to a negative shift in the attitudes of larger ratepayers and officials, who increasingly wanted to dissuade people from applying for assistance and reduce expenditure.

This article reports negative shift in the threshold-voltage in AlGaN/GaN high electron mobility transistor (HEMT) with application of reverse gate bias stress. The device is biased in strong pinch-off and low drain to source voltage condition for a fixed time duration (reverse gate bias stress), followed by measurement of transfer characteristics. Negative threshold voltage shift after application of reverse gate bias stress indicates the presence of more carriers in channel as compared to the unstressed condition. We propose the presence of AlGaN/GaN interface states to be the reason of negative threshold voltage shift, and developed a process to electrically characterize AlGaN/GaN interface states. We verified the results with Technology Computer Aided Design (TCAD) ATLAS simulation and got a good match with experimental measurements.

On the basis of numerical calculations, the experimental results obtained by the authors in the study of the source of negative hydrogen ions of the Penning type with a metal hydride cathode are explained. It was shown that the yield of negative ions depends on the potential at the metal hydride cathode and is determined by the temperature of the plasma electrons. The dependence of this potential on the electron temperature is calculated numerically to ensure the maximum current of negative ions

Nowadays, profile shift is one of the most powerful techniques to achieve high-performance spur gear transmission system. Although this technique has been widely used in industry, its influence on time-varying meshing stiffness (TVMS) and dynamic characteristics is still unclear. This paper presents a novel analytical model of TVMS for profile-shifted spur gears. The modification coefficient and transition curve revise the proposed model. Afterward, numerical simulations are carried out to analyze individual and compound shifts based on a six-degree of freedom gear model. For individual shifts, the positive shift can decrease the gear tooth's stiffness and TVMS so that it causes stronger vibrations in the gear system. On the contrary, the negative shift can improve the gear tooth's stiffness and TVMS, thereby mitigating the gear system's vibration. For compound shift, S0-gearing poses a slight impact on TVMS, but an unneglectable effect on dynamic characteristics. Besides, the S-gearing with the positive compound shift can decrease TVMS and increase vibration. In contrast, the S-gearing with the negative compound shift leads to TVMS rising and significantly reducing vibration. The insightful findings derived from the study can help engineers and manufacturers better understand the operation performance and dynamic features of profile-shifted spur gears.