Electrospun composite nanofibrous scaffolds have been regarded as a potential carrier for local drug delivery to prevent tumor recurrence. Herein, a model drug (paclitaxel) was creatively loaded into ...lignin nanoparticles (PLNPs) and then encapsulated into the polymer of poly (vinyl alcohol)/polyvinyl pyrrolidone which has been fabricated into a composite nanofibrous membrane (PVA/PVP-PLNPs) for use as a drug carrier using the electrospinning technique. The fabricated PVA/PVP-PLNPs membranes exhibited good particle distribution, mechanical properties, thermal stability and biocompatibility. In vitro experiments showed that combining lignin nanoparticles by electrospinning not only improved the drug release profile, but also enhanced the hydrophilicity of nanofibrous membranes which was beneficial to cell adhesion and proliferation. Cellular experiments demonstrated that PVA/PVP-2%PLNPs membrane showed good cell inhibition ability, and the cell survival rate was only 21% at day 7. It indicates that the as-prepared PVA/PVP-PLNPs composite nanofibers are promising candidates for local anticancer therapy.
Abstract
Having a sense of calling toward one's work has key benefits for both the employee and the employer. Yet, little is known about whether and what kind of work climate facilitates employees' ...senses of calling, hindering efforts toward positive changes from managers and organizations. This research introduces the concept of ‘career calling climate’ and describes the development of a scale (i.e., Career Calling Climate Scale) to measure the level of support that a work unit provides for its employees' pursuit of a calling. We established the scale's validity and reliability using survey responses from participants of various occupations and age. To provide evidence of its predictive validity, we examined career calling climate's relation with career callings using a sample of 189 healthcare employees nested in 34 work units. Results suggested that career calling climate predicted individuals' career callings. Implications for theory and practice are discussed.
Although carbon-based single-atom catalysts (SACs), especially Fe-N-C, have been demonstrated as highly promising electrocatalysts for the oxygen reduction reaction (ORR) in alkaline media, their ...application remains a great challenge in acidic proton exchange membrane fuel cells (PEMFCs). Here, by performing high throughput first-principles calculations for 3d, 4d and 5d transition-metal single atoms immobilized on two-dimensional (2D) titanium carbide (Ti
2
CT and Ti
3
C
2
T) surfaces as active sites, we rationally design SACs towards a highly efficient ORR and further propose a composition descriptor to provide atomic-level insights into the structure-activity relationship. Significantly, the parameters involved in the present descriptor can be conveniently obtained from the periodic table of elements. More importantly, we found that the Ti
2
CO
2
-supported non-noble Cu SACs exhibit excellent ORR activity with much lower overpotential (0.25 V) than that of Pt/C (0.4 V), high selectivity for 4e oxygen reduction, excellent stability and acid-resistance and are quite promising ORR catalysts for PEMFCs. The present method can be extended to other 2D transition-metal carbides,
i.e.
, MXenes.
MXene supported single-atom catalysts catalyze the oxygen reduction reaction in a proton exchange membrane fuel cell.
Although carbon-based single-atom catalysts (SACs), especially Fe–N–C, have been demonstrated as highly promising electrocatalysts for the oxygen reduction reaction (ORR) in alkaline media, their ...application remains a great challenge in acidic proton exchange membrane fuel cells (PEMFCs). Here, by performing high throughput first-principles calculations for 3d, 4d and 5d transition-metal single atoms immobilized on two-dimensional (2D) titanium carbide (Ti 2 CT and Ti 3 C 2 T) surfaces as active sites, we rationally design SACs towards a highly efficient ORR and further propose a composition descriptor to provide atomic-level insights into the structure–activity relationship. Significantly, the parameters involved in the present descriptor can be conveniently obtained from the periodic table of elements. More importantly, we found that the Ti 2 CO 2 -supported non-noble Cu SACs exhibit excellent ORR activity with much lower overpotential (0.25 V) than that of Pt/C (0.4 V), high selectivity for 4e oxygen reduction, excellent stability and acid-resistance and are quite promising ORR catalysts for PEMFCs. The present method can be extended to other 2D transition-metal carbides, i.e. , MXenes.
The fabrication of functional wound dressing for effective hemostasis, anti-inflammation as well as angiogenesis is of vital importance. In this paper, a three-dimensional (3D) nanofiber sponge with ...dimethyloxaloglycine (DMOG) loaded mesoporous spheres of derivatives of Prussian blue analogues (PBAs) was prepared (3D-PBA
-DMOG). The nanostructure, composition, and mechanical properties of 3D-PBA
-DMOG were characterized, showing regular nanostructure and good mechanical property. The behavior of
drug release showed the DMOG could achieve long-term and stable release by encapsulating in PBA
microspheres and nanofibers.
coagulation experiments showed that 3D-PBA
-DMOG had effective hemostasis and clotting capacities. In addition, the antioxidant capacity and cell compatibility of 3D-PBA
-DMOG were confirmed. These results indicate that 3D-PBA
-DMOG nanofiber sponge, as a controlled drug release system, may provide a new strategy for promoting angiogenesis and wound healing for clinical applications.
Exploring the Boundaries of Career Calling Chen, Jiatian; May, Douglas R.; Schwoerer, Catherine E. ...
Journal of career development,
04/2018, Volume:
45, Issue:
2
Journal Article
Peer reviewed
The purpose of this research was to examine how the relation between an individual’s calling and his or her job satisfaction, turnover intentions, and career success is affected by two dimensions of ...organizational context, procedural justice and psychological safety. Data were obtained from 526 employees of a law enforcement agency in the Midwest United States. Our results indicate that calling is important to both employees and employers since individuals with higher sense of calling are more satisfied with their jobs, less likely to turn over, and are more content with their careers. Moreover, this study provides evidence that under poor contextual conditions, the relation between calling and job satisfaction is stronger than in good contextual conditions (i.e., procedurally just or psychologically safe contexts). Our findings also suggest that a psychologically safe organizational environment is of some importance to experiencing a feeling of career success for those with a higher sense of calling.
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NUK, OILJ, SAZU, UKNU, UL, UM, UPUK
Manipulating graphene to controllably design three-dimensional (3D) architectures of graphene would be an intriguing approach to prevent two-dimensional (2D) aggregation. Herein, 2D graphene ...nanoribbons (GNRs) have been controllably folded into 3D graphene nanocages (GNCs) by introducing platinum nanoclusters (Pt NCs) forming composite nanoclusters. The van der Waals interaction between the GNR and Pt NC plays a critical role in the self-folding process. The nanocluster shape influences the outer cage of the composite nanocluster largely, in which the spherical Pt NCs could initiate the formation of tetrahedron GNC or graphene nanoscroll, while the other shaped Pt NCs conduct the GNC folding contour the nanocluster geometry. In addition, the sizes of Pt NCs and GNRs also significantly influenced the self-folding process. The controlled folding of 2D GNRs into 3D architectures opens up new avenues for the exploration and fabrication of unique graphene-based nanomaterials and nanodevices toward energy and drug delivery applications.
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IJS, KILJ, NUK, PNG, UL, UM
There is a general increase in the number of patients with non-healing skin wounds, imposing a huge social and economic burden on patients and healthcare systems. Severe skin injury is an important ...clinical challenge. There is a lack of skin donors, and skin defects and scarring after surgery can lead to impaired skin function and skin integrity. Researchers worldwide have made great efforts to create human skin organs but are limited by the lack of key biological structural features of the skin. Tissue engineering repairs damaged tissue by incorporating cells into biocompatible and biodegradable porous scaffolds. Skin tissue engineered scaffolds not only have appropriate physical and mechanical properties but also exhibit skin-like surface topography and microstructure, which can promote cell adhesion, proliferation, and differentiation. At present, skin tissue engineering scaffolds are being developed into clinical applications that can overcome the limitations of skin transplantation, promote the process of wound healing, and repair skin tissue damage. This provides an effective therapeutic option for the management of patients with skin lesions. This paper reviews the structure and function of skin tissue and the process of wound healing, and summarizes the materials and manufacturing methods used to fabricate skin tissue engineering scaffolds. Next, the design considerations of skin tissue engineering scaffolds are discussed. An extensive review of skin scaffolds and clinically approved scaffold materials is presented. Lastly, some important challenges in the construction of skin tissue engineering scaffolds are presented.
This review offers systematic considerations of material design principles and fabrication techniques for biomimetic skin tissue engineering scaffolds.
Polymeric materials have been widely utilized in regenerative medicine because of their ease of manufacturing, flexibility, biocompatibility, as well as good mechanical, chemical, and thermal ...properties. In article number e176, Dong and co‐workers reviewed a variety of polymeric materials and their fabrication methods. The applications of those polymeric materials in regenerative medicine were also proposed.
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FZAB, GIS, IJS, KILJ, NLZOH, NUK, OILJ, SBCE, SBMB, UL, UM, UPUK
The rational design and facile synthesis of highly activated and stable electrocatalysts toward the hydrogen evolution reaction (HER) and the oxygen reduction reaction (ORR) are extremely demanded ...but remain challenging. Herein, a highly efficient bifunctional electrocatalyst composed of rhodium (Rh), cobalt (Co), and iron (Fe) alloy nanoparticles embedded in nitrogen-doped graphene (RhFeCo@NG) is prepared through sequential annealing and the substitution reaction. The as-prepared Rh2.6Fe3Co2.6@NG electrocatalyst achieves an overpotential as low as 25 mV for reaching a current density of 10 mA cm–2 and an ultralow Tafel slope of 29.8 mV dec–1 in 1 M KOH solution for HER, which is even superior to the state-of-the-art platinum (Pt) catalyst. With regard to ORR, for the Rh2.6Fe3Co2.6@NG electrocatalyst, a half-wave potential (E 1/2) of 0.82 V versus reversible hydrogen electrode and excellent long-term stability are achieved. The experimental results illustrate that alloying the Rh atom with the FeCo nanoalloy is mainly responsible for the excellent HER and ORR performances. This study not only provides a robust and promising electrocatalyst for HER and ORR in alkaline media but also sheds light on the devising of efficient and multifunctional catalysts.
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IJS, KILJ, NUK, PNG, UL, UM
