A novel STM for quality atomic resolution with piezoelectric motor of high compactness and simplicity.

Scanning tunneling microscope (STM) is a renowned scientific tool for obtaining high-resolution atomic images of materials. Herein, we present an innovative design of the scanning unit with a compact yet powerful inertial piezoelectric motor inspired by the Spider Drive motor principle. The scanning unit mainly consists of a small 9 mm long piezoelectric tube scanner (PTS), one end of which is coaxially connected to the main sapphire body of the STM. Of particular emphasis in this design is the piezoelectric shaft (PS), constructed from piezoelectric material instead of conventional metallic or zirconium materials. The PS is a rectangular piezoelectric stack composed of two piezoelectric plates, which are elastically clamped on the inner wall of the PTS via a spring strip. The PTS and PS expand and contract independently with each other to improve the inertial force and reduce the threshold voltage. To ensure the stability of the PS and balance the stepping performance of the inertial motor, a counterweight, and a matching conical spring are fixed at the tail of the PS. This innovative design allows for the assessment of scanning unit performance by applying a driving signal, threshold voltage is 50 V at room temperature. Step sizes vary from 0.1 to 1 µm by changing the driving signal at room temperature. Furthermore, we successfully obtained atomic-resolution images of a highly oriented pyrolytic graphite (HOPG) sample and low drift rates of 23.4 pm/min and 34.6 pm/min in X-Y plane and Z direction, respectively, under ambient conditions. This small, compact STM unit has the potential for the development of a rotatable STM for use in cryogen-free magnets, and superconducting magnets.

Glovebox-assisted magnetic force microscope for studying air-sensitive samples in a cryogen-free magnet.

Most known two-dimensional magnets exhibit a high sensitivity to air, making direct characterization of their domain textures technically challenging. Herein, we report on the construction and performance of a glovebox-assisted magnetic force microscope (MFM) operating in a cryogen-free magnet, realizing imaging of the intrinsic magnetic structure of water and oxygen-sensitive materials. It features a compact tubular probe for a 50 mm-diameter variable temperature insert installed in a 12 T cryogen-free magnet. A detachable sealing chamber can be electrically connected to the tail of the probe, and its pump port can be opened and closed by a vacuum manipulator located on the top of the probe. This sealing chamber enables sample loading and positioning in the glove box and MFM transfer to the magnet maintained in an inert gas atmosphere (in this case, argon and helium gas). The performance of the MFM is demonstrated by directly imaging the surface (using no buffer layer, such as h-BN) of very air-sensitive van der Waals magnetic material chromium triiodide (CrI3) samples at low temperatures as low as 5 K and high magnetic fields up to 11.9 T. The system's adaptability permits replacing the MFM unit with a scanning tunneling microscope unit, enabling high-resolution atomic imaging of air-sensitive surface samples.

Atomic resolution imaging using a novel, compact and stiff scanning tunnelling microscope in cryogen-free superconducting magnet.

We present the design and performance of a novel scanning tunnelling microscope (STM) operating in a cryogen-free superconducting magnet. Our home-built STM head is compact (51.5 mm long and 20 mm in diameter) and has a single arm that provides complete openness in the scanning area between the tip and sample. The STM head consists of two piezoelectric tubes (PTs), a piezoelectric scanning tube (PST) mounted on a well-polished zirconia shaft, and a large PT housed in a sapphire tube called the motor tube. The main body of the STM head is made of tantalum. In this design, we fixed the sapphire tube to the frame with screws so that the tube's position can be changed quickly. To analyse the stiffness of the STM head unit, we identified the lowest eigenfrequencies with 3 and 4 kHz in the bending modes, 8 kHz in a torsional mode, and 9 kHz in a longitudinal mode by finite element analysis, and also measured the low drift rates in the X-Y plane and in the Z direction. The high performance of the home-built STM was demonstrated by images of the hexagonal graphite lattice at 300 K and in a sweeping magnetic field from 0 T to 9 T. Our results confirm the high stability, vibration resistance, insensitivity to high magnetic fields and the application potential of our newly developed STM for the investigation of low-frequency systems with high static support stiffness in physics, chemistry, material and biological sciences.

Cultural differences in explicit and implicit support provision and underlying motivations for self-esteem, closeness, and relational concerns.

This research explores how culture influences the motivations underlying explicit (emotional and instrumental) and implicit (companionship and attentiveness) support provision. Two studies (N = 1,106) compared the responses of European Americans and Japanese individuals to a close other's stressful event. The results showed that European Americans were more likely than Japanese to provide explicit support and more motivated to increase the close other's self-esteem and feeling of closeness. Conversely, Japanese individuals were more likely to provide attentiveness support, motivated by concern for an entire group and a friend. These findings support the motivation as a mediator hypothesis. On the other hand, the culture as a moderator hypothesis applied to the association between concern for an entire group motivation and implicit support provision. Specifically, concern for an entire group motivation predicted companionship support provision only in Japanese, while it predicted attentiveness support provision mainly in European Americans.

Perceptions of the motivational climate, basic psychological needs, and life skills development in Chinese physical education students.

Introduction: Life skills can have a positive impact on young people's mental health, academic performance, and overall well-being. Physical education (PE) is viewed as a promising setting for developing students' life skills, but less is known about this in non-English speaking countries such as China. Based on the integration of Self-Determination Theory (SDT) and Achievement Goal Theory (AGT), we aimed to examine the relationships between students' perceptions of the teacher-initiated motivational climate (mastery- or performance-oriented) and their life skills development in PE, as well as the mediating role of their basic psychological needs (BPNs) (satisfaction or frustration). Methods: We employed a cross-sectional survey. Chinese students (N = 533, Age range = 13-18 years) completed measures assessing these variables. We fulfilled correlational and mediational analyses. Results: These findings showed that mastery climate was positively associated with needs satisfaction (r = 0.66) and eight life skills (r range = 0.44-0.61), whereas negatively associated with needs frustration (r = -0.49). Performance climate was positively related to needs frustration (r = 0.52), but negatively related to needs satisfaction (r = -0.38) and eight life skills (r range = -0.28 - -0.15). Needs satisfaction was positively (r range = 0.44-0.65), while needs frustration was negatively (r range = -0.50 - -0.34) linked with eight life skills. Furthermore, needs satisfaction positively mediated the effect of mastery climate on life skills development, but it is not found that needs frustration mediated the effect of performance climate on life skills besides goal setting, social skills, and time management. Conclusion: In conclusion, our study extended the previous literature on life skills in PE, and highlighted the roles of motivational climate and BPNs on students' life skills development. In practice, PE teachers should be encouraged to create a mastery climate as well as avoid a performance climate, to foster students' BPNs satisfaction, which in turn, promote their life skills development.

Can fiscal decentralization and farmers' use of internent be the route to the digitalization performance in China? A novel approach towards unlocking the role of online marketing behavior and performance of agricultural products.

It is believed that the respondents' disadvantageous positions and the information asymmetry that exists between them are the bottlenecks that contribute to the stagnation of trades and the poor revenue that respondents receive from agro-products. Digitalization and fiscal decentralization both play an important part in helping to increase the information literacy of respondents who live in rural areas. The purpose of this study is to investigate the theoretical effects that the digital revolution has had on environmental behavior and performance, and it also analyzes the part that digitalization plays in the process of fiscal decentralization. This study investigates the impact that farmers' usage of the Internet has on their information literacy, online sales behavior, and online sales performance using research data collected from 1338 farmers in China primarily produce pears. Primary data was collected and utilized to develop a structural equation model, using the partial least squares (PLS) and bootstrapping methods; according to the findings, the use of the Internet by farmers has a significant positive effect on the improvement of their information literacy, and it will promote their online sales of pear through the improvement of their information literacy. The results show that the use of the Internet by farmers will improve the online sales performance of pear due to the improvement of farmers' information literacy.

Cryogenic spectroscopic imaging scanning tunnelling microscope in a water-cooled magnet down to 1.7 K.

Spectroscopic-imaging scanning tunnelling microscope (SI-STM) in a water-cooled magnet (WM) at low temperature has long been desirable in the condensed matter physics area since it is crucial for addressing various scientific problems, such as the behaviour of Cooper electrons crossing Hc2 in a high-temperature superconductor. Here we report on the construction and performance of the first atomically resolved cryogenic SI-STM in a WM. It operates at low temperatures of down to 1.7 K and in magnetic fields of up to 22 T (the WM's upper safety limit). The WM-SI-STM unit features a high-stiffness sapphire-based frame with the lowest eigenfrequency being 16 kHz. A slender piezoelectric scan tube (PST) is coaxially embedded in and glued to the frame. A well-polished zirconia shaft is spring-clamped onto the gold-coated inner wall of the PST to serve both the stepper and the scanner. The microscope unit as a whole is elastically suspended in a tubular sample space inside a 1K-cryostat by a two-stage internal passive vibrational reduction system, achieving a base temperature below 2 K in a static exchange gas. We demonstrate the SI-STM by imaging TaS2 at 50 K and FeSe at 1.7 K. Detecting the well-defined superconducting gap of FeSe, an iron-based superconductor, at variable magnetic fields demonstrates the device's spectroscopic imaging capability. The maximum noise intensity at the typical frequency is 3 pA per square root Hz at 22 T, which is only slightly worse than at 0 T, indicating the insensitivity of the STM to harsh conditions. In addition, our work shows the potential of SI-STMs for use in a WM and hybrid magnet with a 50 mm-bore size where high fields can be generated.

Cross-cultural adaptation of Chinese international students: Effects of distant and close support-seeking.

Introduction: Social support-seeking is considered to be an effective way for international students to cope with their acculturative stress and contribute to cross-cultural adaptation. In addition to support from people in the host country (close support), the ease of online communication now allows international students to receive additional support from people back in their home country (distant support). However, little research has investigated whether distant support works as effectively as close support. In two studies, we examined the differential effect of distant and close support-seeking on the psychological adaptation of Chinese international students in the host country and how acculturation orientations relate to the use of these two types of support. Methods: Chinese international students in Japan (Study 1; N = 172) and the United States (Study 2; N = 118) completed an online survey that assessed participants' host/home culture orientation, distant emotional/instrumental support-seeking, close emotional/instrumental support-seeking, and psychological adaptation. Results: Results showed that distant emotional support-seeking negatively predicted psychological adaptation in the host country. Nevertheless, distant emotional support-seeking alleviated feelings of loneliness in Chinese international students as close emotional support-seeking did (Study 2). Also, the results showed that international students with higher home-culture orientation sought more distant support, whereas those with higher host-culture orientation sought more close support. Further, Chinese-culture orientation increased distant emotional support-seeking, decreasing psychological adaptation as well as loneliness. Discussion: These findings highlight the importance of considering the source and types of support when discussing the implications of social support for the cross-cultural adaptation of international students.

Atomically resolved low-temperature scanning tunneling microscope operating in a 22 T water-cooled magnet.

We present the design and construction of a nonmetallic tip-sample mechanical loop featured Scanning Tunneling Microscope (STM) that operates in a 22 T water-cooled magnet at a low temperature of l.8 K. The STM head mainly consists of a spider-drive motor, stand-alone scanner, moveable sapphire sample holder, and sapphire frame. All parts exist in the tip-sample mechanical loop are made of sapphire to reduce the interference from high magnetic fields. Except for the necessary movement of the tip and scanner, all STM parts are stationary. More importantly, the tip-sample mechanical loop is separate from the motor after detecting the tunneling current, which helps prevent the high voltage signal interference from entering the tip-sample junction, leading to a high stable imaging. A Janis liquid helium cryostat is used to obtain a variable temperature range from 1.8 K to 300 K, and the STM head is cooled down via helium exchange gas. The STM head hangs at the bottom of a probe with a two-stage spring suspension to prevent the huge vibration generated by the water-cooled magnet from entering the tip-sample junction. The performance is demonstrated by atomically resolved STM images of graphite surface at 0 T and 22.8 T under room temperature. Furthermore, the obtained atomic-resolution images of NbSe2 at 1.8 K and 22 T, as well as high-resolution dI/dV spectrums at temperatures from 1.8 K to 8.5 K and magnetic fields from 0 T to 22 T are displayed. This is the first STM capable of atomic-resolution imaging and dI/dV measurement at 1.8 K in a 22 T water-cooled magnet. The high immunity to the magnetic field makes the nonmetallic tip-sample mechanical loop widely useable for atomic-resolution STM imaging in ultra-high magnetic field conditions.

Development and Psychometric Evaluation of the Chinese Version of the Life Skills Scale for Physical Education.

Research on life skills in physical education (PE) has gained great attention in recent years. However, there is a need to translate life skills measures for PE into other languages. This research adapted the Life Skills Scale for PE (LSSPE) into Chinese and provided evidence for its validity and reliability. In Study 1, the scale was cross-culturally adapted through translation and back-translation, expert feedback, pilot testing, and scale refinement to provide evidence for the content validity of the scale. Study 2 provided evidence for the factorial validity, internal consistency reliability, and test-retest reliability of the scale by testing it with 583 students. Study 3, with 390 students, provided evidence for the nomological validity of the measure, with results showing perceived teacher autonomy support and students' basic need satisfaction were positively associated with life skills development in PE, and that controlling teaching and basic need frustration were negatively associated with life skills development. In conclusion, the results illustrate that the LSSPE can be used to evaluate Chinese-speaking students' life skills development in PE.

A planar piezoelectric motor of two dimensional XY motions driven by one cross-shaped piezoelectric unit: A new principle.

We present a two-degree-of-freedom piezoelectric motor, which is driven by a simple cross-shaped piezo unit. Here, not only the structure of high novelty and simplicity but also the working principle is new. The cross-shaped piezo unit is sandwiched between top and bottom guiding plates with roughly equal pressing forces applied between the four free ends of the piezo unit and the plates. The working principle is as follows: A pair of opposite arms of the piezo unit quickly and simultaneously expand and contract periodically in the X direction, which results in a vanishing total friction force in the X direction; meanwhile, the other two arms in the Y direction deform slowly in a push-pull manner, which will move the aforementioned X-direction arms a step in the Y direction; then, the Y direction piezo arms restore their initial states slowly one by one. Repeating these actions will produce continuous stepping in the Y direction. Because the structure is symmetric in X and Y directions, we can similarly produce stepping in the X direction. The advantages are obvious: compact, rigid, and planar, which are all important for high stability and, hence, crucial in building an atomically resolved scanning probe microscope.

Cultural differences in social support seeking: The mediating role of empathic concern.

Prior research has found that East Asians are less willing than Westerners to seek social support in times of need. What factors account for this cultural difference? Whereas previous research has examined the mediating effect of relational concern, we predicted that empathic concern, which refers to feeling sympathy and concern for people in need and varies by individuals from different cultures, would promote support seeking. We tested the prediction in two studies. In Study 1, European Canadians reported higher empathic concern and a higher frequency of support seeking, compared to the Japanese participants. As predicted, cultural differences in social support seeking were influenced by empathic concern. In Study 2, both empathic concern and relational concern mediated cultural differences in support seeking. Japanese with lower empathic concern but higher relational concern were more reluctant than European Americans to seek social support during stressful times. Finally, loneliness, which was more prevalent among the Japanese than among the European Americans, was partially explained by social support seeking.

Oxytocin Receptor Gene (OXTR) and Childhood Adversity Influence Trust.

Early-life environments have been associated with various social behaviors, including trust, in late adolescence and adulthood. Given that the oxytocin receptor gene polymorphism (OXTR rs53576) moderates the impact of childhood experience on social behaviors, in the present study, we examined the main effect of childhood adversity through a self-report measure and its interactions with OXTR rs53576 on general trust among 203 Japanese and 200 European Canadian undergraduate students. After controlling for the effect of culture, the results indicated that childhood adversity had a negative association with general trust, and that OXTR rs53576 moderated the impact of childhood adversity on general trust. Specifically, the negative association between childhood adversity and general trust is only significant among homozygote A-allele carriers. These findings demonstrated that OXTR rs53576 moderated the relations between childhood experiences and social functioning in early adulthood.

Brain Structural and Functional Substrates of Personal Distress in Empathy.

Empathy is the capacity to understand and experience the feeling state of others. While individuals attribute negative empathic responses to their own feelings, they would endure personal distress that can be harmful to social interaction. However, the neural mechanism of personal distress remains unclear. Here, we examined the neural substrates of personal distress by combining structural (Voxel-based morphometry (VBM)) and functional (resting-state functional connectivity (FC) analysis) MRI approaches in 53 college students (aged 19-26). A negative correlation was found between a trait measure of personal distress and gray matter (GM) volume in the dorsal medial prefrontal cortex (dmPFC). FC analyses with the dmPFC as a seed further revealed that the connectivity between the dmPFC and posterior insula was positively correlated with the personal distress, and the connectivities between the dmPFC and the anterior middle cingulate cortex, left lateral frontal cortex, and left inferior parietal gyrus were negatively correlated with the personal distress. Our results suggested that personal distress is underlain by neural substrates associated with both cognitive and affective mechanisms. Taken together, the structural and functional correlates of personal distress revealed in the present findings shed new light into the understanding of empathy.

Does agricultural ecosystem cause environmental pollution in Pakistan? Promise and menace.

The increasing trend of atmospheric carbon dioxide (CO2) is the main cause of harmful anthropogenic greenhouse gas emissions, which may result in environmental pollution, global warming, and climate change. These issues are expected to adversely affect the agricultural ecosystem and well-being of the society. In order to minimize food insecurity and prevent hunger, a timely adaptation is desirable to reduce potential losses and to seek alternatives for promoting a global knowledge system for agricultural sustainability. This paper examines the causal relationship between agricultural ecosystem and CO2 emissions as an environmental pollution indicator in Pakistan from the period 1972 to 2014 by employing Johansen cointegration, autoregressive distributed lag (ARDL) model, and Granger causality approach. The Johansen cointegration results show that there is a significant long-run relationship between the agricultural ecosystem and the CO2 emissions. The long-run relationship shows that a 1% increase in biomass burned crop residues, emissions of CO2 equivalent of nitrous oxide (N2O) from synthetic fertilizers, stock of livestock, agricultural machinery, cereal production, and other crop productions will increase CO2 emissions by 1.29, 0.05, 0.45, 0.05, 0.03, and 0.65%, respectively. Further, our finding detects that there is a bidirectional causality of CO2 emissions with rice area paddy harvested, cereal production, and other crop productions. The impulse response function analysis displays that biomass-burned crop residues, stock of livestock, agriculture machinery, cereal production, and other crop productions are significantly contributing to CO2 emissions in Pakistan.

Factors influencing the adoption of improved cultivars: a case of peach farmers in Pakistan / Fatores que influenciam a adoção de cultivares melhoradas: um caso de produtores de pêssego no Paquistão

ABSTRACT: This study aimed to investigate factors influencing the adoption of improved cultivars (ICs) in peach production in Khyber Pakhtunkhwa province of Pakistan. A total of 270 respondents were randomly selected from the three different cultivated areas of Khyber Pakhtunkhwa, namely, Peshawar, Nowshera and Swat. Binary choice model was used in this study to categorise the ICs of peach farmers into adoption and non-adoption. The study identifies that socio-economic, institutional farm resources, and climatic factors are influencing the adoption of ICs of peach production. Results of the estimated model reveal that farmer's age, education, household size, membership, cell phone, farm size, extension services and the role of the non-government organization have a positive effect on adoption of ICs. In addition, farmer's experience, off-farm income, livestock and machinery ownership, credit access and inputs prices have a positive and significant impact on ICs adoption. Moreover, results of the logit model demonstrate that climatic related factors have a highly significant and positive impact on the adoption of ICs. These results suggested that institutional services should be strengthened to provide managerial and technical skills on ICs technology adoption and on time provision of financial services to enhance the productivity of peach farmers.

RESUMO: Este estudo tem como objetivo investigar os fatores que influenciam a adoção de cultivares melhoradas (ICs) na produção de pessegueiros na província de Khyber Pakhtunkhwa, no Paquistão. Um total de 270 entrevistados foram selecionados aleatoriamente a partir das três diferentes áreas cultivadas de Khyber Pakhtunkhwa, Peshawar, Nowshera e Swat. O modelo de escolha binária foi usado neste estudo para categorizar os ICs dos produtores de pêssego em adoção e não-adoção. O estudo identifica que fatores socioeconômicos, institucionais, recursos agrícolas e climáticos influenciam a adoção de ICs de produção de pêssego. Os resultados do modelo estimado revelam que a idade do agricultor, educação, tamanho do agregado familiar, adesão, telefone celular, tamanho da fazenda, serviços de extensão e o papel da organização não-governamental têm efeito positivo sobre a adoção de ICs. Além disso, a experiência do agricultor, a renda fora da propriedade, a posse de gado e maquinaria, acesso ao crédito e preços dos insumos têm um impacto positivo e significativo na adoção dos ICs. Os resultados do modelo logit demonstram que os fatores climáticos relacionados têm um impacto altamente significativo e positivo na adoção de ICs. Estes resultados sugerem que os serviços institucionais devem ser fortalecidos para prover habilidades gerenciais e técnicas na adoção de tecnologia de ICs e no fornecimento de serviços financeiros para aumentar a produtividade dos produtores de pêssego.

Testing long-run relationship between agricultural gross domestic product and fruits production: evidence from Pakistan / Teste de relação de longo prazo entre o produto interno bruto agrícola e produçãode frutos: evidência do Paquistão

ABSTRACT: This paper analyses the long-run relationship between agricultural gross domestic product (GDP) and fruits production of Pakistan's economy over a period of 1961-2015 by employing Johansen and autoregressive distributed lag (ARDL) modern econometric technique. Three fruits were selected namely mango, apple and peach in this study. Augmented Dickey-Fuller and Phillips-Perron tests were used to check the data stationarity and conclude that the series are integrated of order one. The Johansen approach was applied to check the joint evolution of all the variables for co-integration. The Johansen test suggests that a long-run co-integration exists between agricultural GDP and fruits production. Results of the ARDL model (Bound test) detect the existence of long-run relationship between agricultural GDP and fruits production. The coefficient of the short-run form of ARDL model reveals that all the fruits have a positive impact on agricultural GDP. Moreover, the coefficients of the long-run form of ARDL model have apositive and significant influence on agricultural GDP of Pakistan. These results suggest that a 1% increase in mango, apple and peach production will increase agricultural GDP by 0.06%, 0.03% and 0.03% respectively. Finally, forecast error variance decomposition and impulse response function results depict that mango, apple and peach production significantly contributes to agricultural GDP in the case of Pakistan.

RESUMO: Este artigo analisa a relação de longa duração entre o Produto Interno Bruto agrícola (PIB) e a produção de frutos na economia do Paquistão durante um período de 1961-2015, empregando Johansen e o modelo ARDL (Autoregressive Distributed Lag) técnica de cointegração ou técnica de cointegração vinculada. Três frutas foram selecionadas neste estudo: manga, maçã e pêssego. Testes aumentados de Dickey-Fuller e Phillips-Perron foram utilizados para verificar a estacionária de dados e concluir que a série está integrada na ordem um. A abordagem de Johansen foi aplicada para verificar a evolução conjunta de todas as variáveis para a cointegração. O teste de Johansen sugere que existe uma cooperação de longa duração entre o PIB agrícola e a produção de frutos. Os resultados do modelo ARDL (Bound test) detectam a existência de uma relação de longa duração entre o PIB agrícola e a produção de frutos. O coeficiente da forma de curto prazo do modelo ARDL revela que todos os frutos têm um impacto positivo no PIB agrícola. Além disso, os coeficientes da forma de longo prazo do modelo ARDL têm uma influência positiva e significativa sobre o PIB agrícola do Paquistão. Estes resultados sugerem que um aumento de 1% na produção de manga, maçã e pêssego irá aumentar o PIB agrícola em 0,6%, 0,3% e 0,3%, respectivamente. Finalmente, a previsão de desvio de erros e resultados da função de resposta de impulso retratam que a produção de manga, maçã e pêssego contribui significativamente para o PIB agrícola do Paquistão.