Scientists over the world are inspired by biological nanomotors and try to mimic these complex structures. In recent years multiple nanomotors have been created for various fields, such as biomedical ...applications or environmental remediation, which require a different design both in terms of size and shape, as well as material properties. So far, only relatively simple designs for synthetic nanomotors have been reported. Herein, we report an approach to create biodegradable polymeric nanomotors with a multivalent design. PEG-PDLLA (poly(ethylene glycol)-b-poly(D,L-lactide)) stomatocytes with azide handles were created that were selectively reduced on the outside surface by TCEP (tris(2-carboxyethyl)phosphine) functionalized beads. Thereby, two different functional handles were created, both on the inner and outer surface of the stomatocytes, providing spatial control for catalyst positioning. Enzymes were coupled on the inside of the stomatocyte to induce motion in the presence of fuel, while fluorophores and other molecules can be attached on the outside.
This Letter reports a measurement of the flux and energy spectrum of electron antineutrinos from six 2.9 GWth nuclear reactors with six detectors deployed in two near (effective baselines 512 and 561 ...m) and one far (1579 m) underground experimental halls in the Daya Bay experiment. Using 217 days of data, 296 721 and 41 589 inverse β decay (IBD) candidates were detected in the near and far halls, respectively. The measured IBD yield is (1.55±0.04) ×10(-18) cm(2) GW(-1) day(-1) or (5.92±0.14) ×10(-43) cm(2) fission(-1). This flux measurement is consistent with previous short-baseline reactor antineutrino experiments and is 0.946±0.022 (0.991±0.023) relative to the flux predicted with the Huber-Mueller (ILL-Vogel) fissile antineutrino model. The measured IBD positron energy spectrum deviates from both spectral predictions by more than 2σ over the full energy range with a local significance of up to ∼4σ between 4-6 MeV. A reactor antineutrino spectrum of IBD reactions is extracted from the measured positron energy spectrum for model-independent predictions.
Spatial patterns in trait variation reflect underlying community assembly processes, allowing us to test hypotheses about their trait and environmental drivers by identifying the strongest correlates ...of characteristic spatial patterns. For 43 evergreen tree species (> 1cm dbh) in a 20 ha seasonal tropical rainforest plot in Xishuangbanna, China, we compared the ability of drought tolerance traits, other physiological traits and commonly measured functional traits to predict the spatial patterns expected from the assembly processes of habitat associations, niche overlap-based competition, and hierarchical competition. We distinguished the neighborhood-scale (0- 20m) patterns expected from competition from larger-scale habitat associations with a wavelet method. Species' drought tolerance and habitat variables related to soil water supply were strong drivers of habitat associations, and drought tolerance showed a significant spatial signal for influencing competition. Overall, the traits most strongly associated with habitat, as quantified using multivariate models, were leaf density, leaf turgor loss point (πtlp; also known as the leaf wilting point), and stem hydraulic conductivity (r2 range for the best fit models = 0.27-0.36). At neighborhood scales, species spatial associations were positively correlated with similarity in πtlp, consistent with predictions for hierarchical competition. Although the correlation between πtlp and interspecific spatial associations was weak (r2 < 0.01), this showed a persistent influence of drought tolerance on neighborhood interactions and community assembly. Quantifying the full impact of traits on competitive interactions in forests may require incorporating plasticity among individuals within species, especially among specific life stages, and moving beyond individual traits to integrate the impact of multiple traits on whole-plant performance and resource demand.
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Nursing students in the present sample who have experienced childhood adversity have a certain level of post‐traumatic growth.
If introduced into nursing curricula, emotional ...intelligence interventions may increase emotional coping resources and enhance social skills for nurses, which may benefit their long‐term occupational health.
As researchers consider personal resilience a strategy for responding to workplace adversity in nurses, resilience building should be incorporated into nursing education.
This is a preliminary study that may guide future investigations of the curvilinear relationship rather than linear relationship between post‐traumatic growth and positive factors in the special sample of nursing students.
Resilience, emotional intelligence and post‐traumatic growth may benefit nursing students’ careers and personal well‐being in clinical work. Developing both their emotional intelligence and resilience may assist their individual post‐traumatic growth and enhance their ability to cope with clinical stress. To investigate the relationships among post‐traumatic growth, emotional intelligence and psychological resilience in vocational school nursing students who have experienced childhood adversities, a cross‐sectional research design with anonymous questionnaires was conducted and self‐report data were analysed. The Childhood Adversities Checklist (Chinese version), Posttraumatic Growth Inventory, Emotional Intelligence Scale and the 10‐item Connor–Davidson Resilience Scale were used. Survey data were collected from 202 Chinese vocational school nursing students during 2011. Post‐traumatic growth was associated with emotional intelligence and psychological resilience. Results indicated a curvilinear relationship between emotional intelligence and post‐traumatic growth, and between psychological resilience and post‐traumatic growth. Moderate‐level emotional intelligence and psychological resilience were most associated with the greatest levels of growth. The results imply that moderate resilience and emotional intelligence can help nursing students cope with adversity in their future clinical work. This study first provided preliminary data suggesting the curvilinear relationship rather than linear relationship between post‐traumatic growth and positive factors in the sample of nursing students.
Background To investigate the prevalence of Internet addiction among Chinese adolescents and to explore the psychological features associated with Internet addiction.
Methods A total of 2620 high ...school students from four high schools in Changsha City were surveyed using Diagnostic Questionnaire for Internet Addiction (YDQ), Eysenck Personality Questionnaire (the edition for children, EPQ), Time Management Disposition Scale (TMDS) and Strengths and Difficulties Questionnaire (SDQ). The mean age of whole sample was 15.19 years (ranging from 12 years to 18 years). According to the modified YDQ criteria by Beard, 64 students who were diagnosed as Internet addiction (the mean age: 14.59 years) and 64 who were diagnosed as being normal in Internet usage (the mean age: 14.81 years) were included in a case–control study.
Results The rate of Internet use among the surveyed adolescents was 88%, among which the incidence rate of Internet addiction was 2.4%. The Internet addiction group had significantly higher scores on the EPQ subscales of neuroticism, psychoticism, and lie than the control group (P < 0.05). The Internet addiction group scored lower than the control group on the TMDS subscales of sense of control over time, sense of value of time, and sense of time efficacy (P < 0.05). Compared with the control group, the Internet addiction group had also significantly higher scores on the SDQ subscales of emotional symptoms, conduct problems, hyperactivity, total difficulties and lower scores on the subscale of prosocial behaviours (P < 0.05).
Conclusions The present study suggests that Internet addiction is not rare among Chinese adolescents. In addition, adolescents with Internet addiction possess different psychological features when compared with those who use the Internet less frequently.
One of the most promising approaches to reach a high gain in inertial confinement fusion is the fast ignition scheme. In this scheme, a relativistic electron beam is generated; this passes through ...the imploded plasma and deposits parts of its energy in the core. However, the large angular spread of the relativistic electron beam and the poorly controlled compression of the target affect realization of the fast ignition technique. Here, we demonstrate that indirectly driven (that is, driven by X-rays generated inside a gold hohlraum) implosions with a ‘high-foot’ and a short-coast time of less than 200 ps allow us to tightly compress the shell. Furthermore, we show the ability to optimize the symmetry of the imploding shell by changing the hohlraum length, successfully tuning a suitable tube-shaped shell to compensate for the large angular spread of the relativistic electron beam and to enhance the electron-to-core coupling efficiency via resistive magnetic fields. Benefiting from those experimental techniques, a significant enhancement in neutron yield was achieved in our indirectly driven fast ignition experiments. These results pave the way towards high-coupling fast ignition experiments with indirectly driven targets similar to those at the National Ignition Facility.Experiments realizing the indirect-drive fast ignition scheme for inertial confinement fusion are reported. Enabled by a tightly compressed target, an increase of neutron yield is observed.
An expanded model for the thermodynamics of co-clusters and their strengthening is presented and applied to predict co-cluster formation and strengthening in Al–Mg–Si alloys. The models were tested ...against data on a wide range of Al–Mg–Si alloys aged at room temperature. The strengthening due to co-clusters is well predicted. The formation of co-clusters was studied in an Al–0.5at.% Mg–1at.% Si alloy using three-dimensional atom probe analysis. The results correspond well with the model. It is shown that in general (short-range) order strengthening due to co-clusters will be the main strengthening mechanism in these alloys. Apart from the co-clusters, Si clusters also form, but due to their low enthalpy of formation they contribute little to the strength.
•A comprehensive study was conducted upon Al–Mg–Si alloys with differing Mg/Si ratio and Cu content.•Corrosion investigations included naturally aged, under-, peak- and over-aged conditions.•Ageing ...conditions and solute content all had an influence on the corrosion (and morphology).•Cu content was dominant over the Mg/Si ratio in terms of corrosion response.
Specially prepared 6xxx series aluminium alloys (Al–Mg–Si) with different Mg/Si ratios and Cu contents were investigated in the naturally aged, under-aged, peak-aged and over-aged conditions. Potentiodynamic polarisation and immersion testing in 0.1M NaCl were used to investigate the corrosion behaviour of such alloys in a general sense. Results reveal a significant dependence of the corrosion rate and morphology on the ageing conditions and solute content. Whilst contributing to broader understanding of 6xxx alloy corrosion, we note that corrosion rate is lowest in the naturally aged condition and is principally influenced by Cu and subsequently by the Mg/Si ratio.
Drought events may increase the likelihood that the plant water transport system becomes interrupted by embolism. Yet our knowledge about the temporal frequency of xylem embolism in the field is ...frequently lacking, as it requires detailed, long‐term measurements.
We measured xylem embolism resistance and midday xylem water potentials during the consecutive summers of 2019 and 2020 to estimate maximum levels of embolism in leaf and stem xylem of ten temperate angiosperm tree species. We also studied vessel and pit membrane characteristics based on light and electron microscopy to corroborate potential differences in embolism resistance between leaves and stems.
Apart from A. pseudoplatanus and Q. petraea, eight species experienced minimum xylem water potentials that were close to or below those required to initiate embolism. Water potentials corresponding to ca. 12% loss of hydraulic conductivity (PLC) could occur in six species, while considerable levels of embolism around 50% PLC were limited to B. pendula and C. avellana. There was a general agreement in embolism resistance between stems and leaves, with leaves being equally or more resistant than stems. Also, xylem embolism resistance was significantly correlated to intervessel pit membrane thickness (TPM) for stems, but not to vessel diameter and total intervessel pit membrane surface area of a vessel.
Our data indicate that low amounts of embolism occur in most species during moderate summer drought, and that considerable levels of embolism are uncommon. Moreover, our experimental and TPM data show that leaf xylem is generally no more vulnerable than stem xylem.
Stem and leaf xylem of ten temperate angiosperm species were found to experience minimal levels of embolism formation in the field during two consecutive summers with moderate drought.
Expanding of karst rocky desertification (RD) area in southwestern China is strangling the sustainable development of local agricultural economy. It is important to evaluate the soil fertility at RD ...regions for the sustainable management of karst lands. The changes in 19 different soil fertility-related variables along a gradient of karst rocky desertification were investigated in five different counties belonging to the central Hunan province in China. We used principal component analysis method to calculate the soil data matrix and obtained a standardized integrate soil fertility (ISF) indicator to reflect RD grades. The results showed that the succession of RD had different impacts on soil fertility indicators. The changing trend of total organic carbon (TOC), total nitrogen (TN), available phosphorus, microbial biomass carbon (MBC), and microbial biomass nitrogen (MBN) was potential RD (PRD) > light RD (LRD) > moderate RD (MRD) > intensive RD (IRD), whereas the changing trend of other indicators was not entirely consistent with the succession of RD. The degradation trend of ISF was basically parallel to the aggravation of RD, and the strength of ISF mean values were in the order of PRD > LRD > MRD > IRD. The TOC, MBC, and MBN could be regarded as the key indicators to evaluate the soil fertility.
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