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Scholarly and practitioner interest in authentic leadership has grown at an accelerating rate over the last decade, resulting in a proliferation of publications across diverse social science disciplines. Accompanying this interest has been criticism of authentic leadership theory and the methods used to explore it. We conducted a systematic review of 303 scholarly articles published from 2010 to 2023 to critically assess the conceptual and empirical strengths and limitations of this literature and map the nomological network of the authentic leadership construct. Results indicate that much of the extant research does not follow best practices in terms of research design and analysis. Based on the findings obtained, an agenda for advancing authentic leadership theory and research that embraces a signaling theory perspective is proposed.
For any emerging pathogen, the preferred approach is to drive it to extinction with non-pharmaceutical interventions (NPI) or suppress its spread until effective drugs or vaccines are available. However, this might not always be possible. If containment is infeasible, the best people can hope for is pathogen transmission until population level immunity is achieved, with as little morbidity and mortality as possible.
Methods:
A simple computational model was used to explore how people should choose NPI in a non-containment scenario to minimize mortality if mortality risk differs by age.
Results:
Results show that strong NPI might be worse overall if they cannot be sustained compared to weaker NPI of the same duration. It was also shown that targeting NPI at different age groups can lead to similar reductions in the total number of infected, but can have strong differences regarding the reduction in mortality.
Conclusions:
Strong NPI that can be sustained until drugs or vaccines become available are always preferred for preventing infection and mortality. However, if people encounter a worst-case scenario where interventions cannot be sustained, allowing some infections to occur in lower-risk groups might lead to an overall greater reduction in mortality than trying to protect everyone equally.
OBJECTIVES/GOALS: Underrepresented (UR) biomedical researchers leave research positions at a disproportionate rate. We aim to identify factors associated with confidence in career progression and intent to continue clinical research training in UR post-doctoral fellows and early-career faculty. METHODS/STUDY POPULATION: Building Up is a cluster-randomized trial at 25 academic institutions. In September-October 2020, 224 participants from the Building Up study completed the pre-intervention assessment, which included questions on demographics, science identity, mentoring competency, confidence in career progression, and intent to continue clinical research training. Using multinomial logistic regression controlling for gender and race/ethnicity, we identified factors associated with confidence in career progression, and intent to continue clinical research training. Statistically significant findings are reported. RESULTS/ANTICIPATED RESULTS: The cohort (N=219) is 80% female, 33% non-Hispanic Black, and 34% Hispanic. Having mentors that address diversity was associated with belief that career advancement is as open to them as anyone else (OR=1.7) and confidence in ability to overcome professional barriers (OR=1.4). Higher science identity (OR=4.0) and having mentors who foster independence (OR=1.7) were associated with confidence in ability to progress in career. Higher science identity was also associated with confidence in ability to overcome professional barriers (OR=2.2) and intent to continue studying biomedical sciences (OR=3.4). Being faculty (OR=3.8), higher science identity (OR=3.8), and having mentors that align expectations (OR=2.3) were associated with intent to continue clinical research training. DISCUSSION/SIGNIFICANCE: These findings suggest that science identity and mentoring play key roles in confidence in career progression and intent to continue clinical research training. These factors are important to consider in retaining UR early-career biomedical researchers.
Schistosomiasis has been subjected to extensive control efforts in the People's Republic of China (China) which aims to eliminate the disease by 2030. We describe baseline results of a longitudinal cohort study undertaken in the Dongting and Poyang lakes areas of central China designed to determine the prevalence of Schistosoma japonicum in humans, animals (goats and bovines) and Oncomelania snails utilizing molecular diagnostics procedures. Data from the Chinese National Schistosomiasis Control Programme (CNSCP) were compared with the molecular results obtained.
Sixteen villages from Hunan and Jiangxi provinces were surveyed; animals were only found in Hunan. The prevalence of schistosomiasis in humans was 1.8% in Jiangxi and 8.0% in Hunan determined by real-time polymerase chain reaction (PCR), while 18.3% of animals were positive by digital droplet PCR. The CNSCP data indicated that all villages harboured S. japonicum-infected individuals, detected serologically by indirect haemagglutination assay (IHA), but very few, if any, of these were subsequently positive by Kato-Katz (KK).
Based on the outcome of the IHA and KK results, the CNSCP incorporates targeted human praziquantel chemotherapy but this approach can miss some infections as evidenced by the results reported here. Sensitive molecular diagnostics can play a key role in the elimination of schistosomiasis in China and inform control measures allowing for a more systematic approach to treatment.
To evaluate delivery management and outcomes in fetuses prenatally diagnosed with CHD.
Study design:
A retrospective cohort study was conducted on 6194 fetuses (born between 2013 and 2016), comparing prenatally diagnosed with CHD (170) to those with non-cardiac (234) and no anomalies (5790). Primary outcomes included the incidence of preterm delivery and mode of delivery.
Results:
Gestational age at delivery was significantly lower between the CHD and non-anomalous cohorts (38.6 and 39.1 weeks, respectively). Neonates with CHD had a significantly lower birth weights (p < 0.001). There was an approximately 1.5-fold increase in the rate of primary cesarean sections associated with prenatally diagnosed CHD with an odds ratio of 1.49 (95% CI 1.06–2.10).
Conclusions:
Our study provides additional evidence that the prenatal diagnosis of CHD is associated with a lower birth weight, preterm delivery, and with an increased risk of delivery by primary cesarean section.
Human infection with the emerging avian influenza A(H7N9) virus in China in 2013 has raised global concerns. We conducted a retrospective descriptive study of 27 confirmed human influenza A(H7N9) cases in Jiangsu Province, to elaborate poultry-related exposures and to provide a more precise estimate of the incubation periods of the illness. The median incubation period was 6 days (range 2–10 days) in cases with single known exposure and was 7·5 days (range 6·5–12·5 days) in cases with exposures on multiple days, difference between the two groups was not significant (Z = −1·895, P = 0·058). The overall median incubation period for all patients was estimated to be 7·5 days (range 2–12·5 days). Our findings further highlight the necessity for public health authorities to extend the period of medical surveillance from 7 days to 10 days.
Samples of single-phase Sr2FeMoO6 were successfully prepared by solid-state reaction with long sintering times. The crystal structures of the Sr2FeMoO6 samples were determined from X-ray powder diffraction data using the Rietveld refinement method. The structure results obtained by the Rietveld refinements show that an increase in the total sintering time of the solid-state reaction is an effective method to obtain single Sr2FeMoO6 phase and to improve the ordering of Fe and Mo cations (or reducing antisite defects) in the double-perovskite structure. The volume of the tetragonal unit cell of Sr2FeMoO6 contracts slightly after successive sintering treatments. The averaged Fe-O and Mo-O bond lengths as well as the tilt between the FeO6 and the MoO6 octahedra decrease with increasing total sintering time. Our results suggest that the detected subtle changes in crystal structure, such as bond lengths and bond angles between the Fe and Mo cations and oxygen, in the ordered double-perovskite structure may be responsible for the large effects on previously reported transport and magnetic properties of an oxide metal.
Energetic divergent proton beams can be generated in the interaction of ultra-intense laser pulses with solid-density foil targets via target normal sheath acceleration (TNSA). In this paper, a scheme using a capillary to reduce the proton beam divergence is proposed. By two-dimensional particle-in-cell (PIC) simulations, it is shown that strong transverse electric and magnetic fields rapidly grow at the inner surface of the capillary when the laser-driven hot electrons propagate through the target and into the capillary. The spontaneous magnetic field collimates the electron flow, and the ions dragged from the capillary wall by hot electrons neutralize the negative charge and thus restrain the transverse extension of the sheath field set up by electrons. The proton beam divergence, which is mainly determined by the accelerating sheath field, is therefore reduced by the transverse limitation of the sheath field in the capillary.
A discrete subaortic membrane cannot only cause left ventricular outflow tract obstruction, but can grow onto the aortic valve leaflets. The late finding of this encroachment is aortic valve insufficiency or stenosis. Echocardiography is used to follow the progression of outflow tract obstruction, but its ability to show subaortic membrane encroachment onto the aortic valve is unclear. The purpose of this study is to determine the sensitivity and specificity of echocardiography for diagnosing whether a discrete subaortic membrane involves the aortic valve.
Methods
A pre-operative determination of aortic valve involvement by a discrete subaortic membrane was obtained by review of the official pre-operative echocardiogram reading and a retrospective blinded review of the pre-operative echocardiogram by an independent echocardiographer. These findings were compared to the intra-operative findings.
Results
A total of 48 consecutive patients underwent primary resection for isolated discrete subaortic membrane between October, 1995 and May, 2006. The pre-operative and blinded readings both predicted a statistically lower rate of aortic valve involvement – 35% in 11 of 31 patients and 31% in 10 of 31 patients, respectively – than found at surgery – 65% in 31 of 48 patients. The sensitivity and specificity of pre-operative echocardiography to diagnose aortic valve involvement is 35% and 76%. Overall survival was 100%. There were no strokes, re-operations for bleeding or wound infections, or need for a pacemaker.
Conclusion
Echocardiography is not sensitive in assessing whether a discrete subaortic membrane involves the aortic valve. Since the morbidity and mortality for discrete subaortic membrane resection is negligible, resection may be indicated at the time of diagnosis to minimise aortic valve impairment.
The structure and vibrational spectrum of Gd2 and Gd2C2 endofullerenes are studied through Raman spectroscopy and universal force field (UFF) calculations. Hindered rotations, shown by both theory and experiment, indicate the formation of a Gd–cage bond, which reduces the ideal symmetry of the cage. We have conducted Raman studies of Gd2@C90, Gd2@C79N, and Gd2C2@C92. We have also studied Y2C2@C92 for comparison. Several modes have been identified which provide information about the endohedral complex.
The objective of this study was to determine the effect of stage of lactation on the concentration of polyamines (spermine, spermidine, and putrescine) in sow colostrum and milk. Ten, third parity sows (Landrace×Yorkshire) were sampled throughout a 28-day lactation. Litter size for all sows was standardized at 10 sucking piglets immediately after farrowing. Colostrum collection began at the birth of the first piglet (0 h), and colostrum was subsequently collected 6, 12, 18, and 24 h after farrowing. Sow milk was sampled on days 3, 7, 10, 14, 17, 21, 24 and 28 of lactation. Spermine concentration in sow colostrum was relatively constant for the first 12 h after farrowing and then rapidly increased to 10·26 μmol/l 24 h after farrowing (linear and quadratic effect; P<0·01). In contrast, the concentrations of spermidine and putrescine showed little change during the first 24 h with spermidine concentration in colostrum ranging from 3·76 to 4·54 μmol/l, and putrescine concentration ranging from 1·15 to 1·52 μmol/l. The highest concentration of spermine in sow milk was 18·82 μmol/l, observed on day 7, with levels gradually declining to 4·28 μmol/l by day 28 of lactation (linear and quadratic effect; P<0·01). In contrast, the concentration of spermidine increased during lactation ranging from a low of 4·32 μmol/l on day 7 to a high of 9·01 μmol/l on day 28 of lactation (linear effect P<0·01; quadratic effect P=0·03). Putrescine concentration ranged from 1·53 μmol/l on day 3 to 1·84 μmol/l on day 28 (linear effect P=0·07; quadratic effect P>0·05). The results of this study show sow colostrum and milk provide polyamines for sucking piglets before weaning, which could potentially modulate intestinal maturation.
We have carried out measurements of electromigration-induced strains in copper conductor lines using microbeam energy dispersive x-ray diffraction. Strains developed in random texture damascene Cu 2μm-wide, 0.16 μm-thick conductor lines with TaN liners in low-k dielectric during electromigration at 350°C are much smaller than electromigration-induced strains in (111) fiber texture Al-on-Si, 10μm-wide, SiO2 passivated conductor lines. The reasons for these differences in electromigration behavior may involve the different roles of grain boundary and interface diffusion paths and the different passivation structures and materials for the two types of samples.
Two dark-spored agaric species from Asia are placed in the genus Anamika (Agaricales or euagarics clade). This result is supported by ITS and nLSU-rDNA sequences with strong measures of branch support, in addition to several morphological and ecological similarities. An inclusive ITS study was performed using a mixed model Bayesian analysis that suggests the derived status of Anamika within Hebeloma, thereby rendering Hebeloma a paraphyletic genus. However, the monophyly of Hebeloma cannot be rejected outright given ITS and nLSU-rDNA data. Thus, we propose two new Asian species in Anamika: A. angustilamellata sp. nov. from dipterocarp and fagaceous forests of southwestern China and northern Thailand; and A. lactariolens comb. nov., a Japanese species originally described in the genus Alnicola. A complete description of A. angustilamellata, including illustrations, is provided.
ZnO films with orientations of (001), (110), and (100) were fabricated on silicon by different substrate biases at low temperature. Dynamic cathodoluminescence (CL) dependence on electron bombardment revealed unstable Zn-N bonding if N2 was used as a predecessor. CL under various accelerated voltages showed the possible energies of Zn-N. N-related photoluminescence (PL) at low temperature confirmed that nitrogen was released after annealing. These N-doping behaviors agreed to the theoretical calculation.
Taking advantages of short pulse excitation and time-resolved photoluminescence (PL), we have studied the exciton localization effect in a number of GaAsN alloys and GaAsN/GaAs quantum wells (QWs). In the PL spectra, an extra transition located at the higher energy side of the commonly reported N-related emissions is observed. By measuring PL dependence on temperature and excitation power along with PL dynamics study, the new PL peak has been identified as a transition of the band edge-related recombination in dilute GaAsN alloy and delocalized transition in QWs. Using selective excitation PL we further attribute the localized emission in QWs to the excitons localized at the GaAsN/GaAs interfaces. This interface-related exciton localization could be greatly reduced by a rapid thermal annealing.
We give an overview of the open-boundary planar supercell stack method (OPSSM), as a means for treating 3D quantum transport in mesoscopic tunnel structures. The flexibility of the method allows us to examine a variety of physical phenomena relevant to quantum transport. In this work we focus on the effects of interface roughness and embedded nanostructures in tunnel devices. Four representative applications of OPSSM are discussed: (1) interface roughness in double barrier resonant tunneling structures, (2) self-organized InAs quantum dot insertions in GaAs/AlAs double barrier structures, (3) tunneling characteristics of ultra-thin oxides with interface roughness, and, (4) embedded quantum wire model of dielectric breakdown. These examples demonstrate scattering and localization effects under different biasing conditions.
Due to huge uncertainties in the geometric dimensions of atomic force microscopy (AFM) probes, samples' rheological properties and lateral forces are difficult to measure and compare quantitatively. Hence, mathematical calibration methods fail to calibrate AFM probes accurately. To solve this problem, we will introduce in this paper “blind calibration methods” to determine quantitatively lateral forces, elastic constants and viscosity. For lateral force, a geometry factor is used to calibrate any cantilever using this “blind method”. The essential part of this method is a calibration standard sample that is commercially available. We have chosen silicon for our calibration standard sample and will discuss a cleaning procedure for reproducible lateral force measurements. We will provide an absolute friction value, which will serve as one of three parameters necessary to obtain the geometry factor. The other two components being the normal spring constant and the relative friction signal measured with the cantilever of interest. Further, we will discuss force modulation measurements and the problems that occur around resonances. We will provide a procedure to determine elastic constants also based on the silicon calibration standard. Finally, the “blind calibration method” will also be used to achieve kinematic viscosity values.
A population-based case-control study to determine social and behavioural risk factors for Taenia solium cysticercosis in humans was carried out in a rural area, Shandong province, China. Forty-eight cases with cysticercosis were ascertained through a prevalence survey conducted among 7281 persons in 1993. For each case, four controls residing in the same village and matched for age and sex were randomly selected. Information regarding demographic, social and behavioural factors was collected during house visits through interviews and direct observation. Risk factors strongly associated with human cysticercosis included poor personal hygiene, being unable to recognize cysticerci-containing meat, poor pig-raising practices and a history of passing tapeworm proglottides. The results indicate that health education in combination with chemotherapy for taeniasis is required for the control of cysticercosis in humans.