Background: Smoking continues to be one of the most popular recreational practices despite its known harmful effects. Aim: The purpose of this survey was to assess the prevalence of smoking in the Caribbean and the co...Background: Smoking continues to be one of the most popular recreational practices despite its known harmful effects. Aim: The purpose of this survey was to assess the prevalence of smoking in the Caribbean and the correlation of smoking with the disease states of high blood pressure, diabetes and high cholesterol whose risk is known to be higher among smokers. Findings: Our study found a smoking prevalence of 22% in the population, similar to that reported by the World Health Organization (20%) and a positive correlation between smoking and diabetes. Conclusion: The survey shows that smoking numbers within the population are still high and that smoking increases the risk of certain disease states within smokers. Aggressive global efforts to reduce smoking should continue so as to minimize the negative impact of smoking on health.展开更多
Background:Posttraumatic stress disorder(PTSD)has been associated with volumetric and white matter microstructural changes among general and veteran populations.However,regions implicated have greatly varied and often...Background:Posttraumatic stress disorder(PTSD)has been associated with volumetric and white matter microstructural changes among general and veteran populations.However,regions implicated have greatly varied and often conflict between studies,potentially due to confounding comorbidities within samples.This study compared grey matter volume and white matter microstructure among Australian combat veterans with and without a lifetime diagnosis of PTSD,in a homogenous sample assessed for known confounding comorbidities.Methods:Sixty-eight male trauma-exposed veterans(16 PTSD-diagnosed;mean age 69 years)completed a battery of psychometric assessments and underwent magnetic resonance and diffusion tensor imaging.Analyses included tractbased spatial statistics,voxel-wise analyses,diffusion connectome-based group-wise analysis,and volumetric analysis.Results:Significantly smaller grey matter volumes were observed in the left prefrontal cortex(P=0.026),bilateral middle frontal gyrus(P=0.021),and left anterior insula(P=0.048)in the PTSD group compared to controls.Significant negative correlations were found between PTSD symptom severity and fractional anisotropy values in the left corticospinal tract(R^(2)=0.34,P=0.024)and left inferior cerebellar peduncle(R^(2)=0.62,P=0.016).No connectome-based differences in white matter properties were observed.Conclusions:Findings from this study reinforce reports of white matter alterations,as indicated by reduced fractional anisotropy values,in relation to PTSD symptom severity,as well as patterns of reduced volume in the prefrontal cortex.These results contribute to the developing profile of neuroanatomical differences uniquely attributable to veterans who suffer from chronic PTSD.展开更多
We report a phase inversion polymer coating as a novel concept with potential to prevent clay swelling and fines generation in coal seam gas, or other petroleum, wellbores. Our approach uses polyethersulfone (PES) w...We report a phase inversion polymer coating as a novel concept with potential to prevent clay swelling and fines generation in coal seam gas, or other petroleum, wellbores. Our approach uses polyethersulfone (PES) with N-methyl-2- pyrrolidone (NMP) as a water-soluble solvent to form a dense, low-porosity film across the clay-rich interburden layers, but a porous and permeable membrane on coal seams. This contrasting behaviour occurs because the coal contains much more free water than the clay-rich interburden layers. We demonstrate the efficacy of the method to prevent clay spalling in immersion tests and under a flow of fresh water in a visual swell test apparatus. The clay-rich rocks studied were mudstone and siltstone, and these were dip coated in the PES/NMP solution. The uncoated mudstone swelled and broke apart quickly in the immersion test and visual flow test, but the PES coated rock samples were stable for 30 days. The coated rock and coal samples were characterised by X-ray diffraction, Fourier transform infrared spectroscopy and scanning electron microscopy. The morphology of coated mudstone and coated coal samples showed that the polymer formed a dense layer across the low-permeability mudstone, but an open porous structure on the coal surface. The effect of the coating on the permeability of KCl brine through coal was measured in a core-flood apparatus. Although the permeability of the coal showed some deterioration after coating, from (0.58 ± 0.12) mD to (0.3 ±0.03) mD, these results demonstrate the potential of a smart polymer coating to prevent clay swelling while remaining permeable to gas and water on coal layers.展开更多
BACKGROUND The presence of small air bubbles and foam are an impediment to a successful colonoscopy. They impair an endoscopist’s view and diminish the diagnostic accuracy of the study. This has been particularly not...BACKGROUND The presence of small air bubbles and foam are an impediment to a successful colonoscopy. They impair an endoscopist’s view and diminish the diagnostic accuracy of the study. This has been particularly noted to be of concern with the switch to lower volume polyethylene glycol (PEG) and bisacodyl combination preparation. AIM To evaluate the effect of oral simethicone addition to bowel preparation on intraluminal bubbles reduction during colonoscopy. METHODS Described is a prospective, randomized, multi-center, double-blinded, placebocontrolled study to evaluate the use of premixed simethicone formulation with split-regimen, low-volume PEG-bisacodyl combination bowel preparation for 168 outpatients undergoing screening, surveillance, and diagnostic colonoscopies. Primary outcome includes evaluation of bubbles during colonoscopy graded using the Intraluminal Bubbles Scale. Secondary outcomes include evaluation of the Boston Bowel Preparation Scale (BBPS), total number of polyps, polyp size differentiation, polyp laterality, adenoma detection, mass detection, cecal insertion time, withdrawal time, and patient-reported adverse events. RESULTS Higher Intraluminal Bubbles grades III and IV (less than 75% of the mucosa cleared of bubbles/foam requiring intervention with simethicone infused wash) were detected in the placebo group [Simethicone n = 4/84 vs Placebo n = 20/84 (P = 0.007)]. BBPS total score was 7.42 [standard deviation (SD)=± 1.51] in the simethicone group and 7.28 (SD =± 1.44) in the placebo group (P = 0.542) from a total of 9. Significantly higher number of adenomas were detected in the simethicone group (P = 0.001). CONCLUSION The addition of simethicone to bowel preparation is well advised for its antifoaming properties. The results of this study suggest that addition of oral simethicone can improve bowel wall visibility.展开更多
The phase equilibrium information of slag plays an important role in pyrometallurgical processes to obtain optimum fluxing conditions and operating temperatures.The smelting reduction of titanomagnetite and ilmenite o...The phase equilibrium information of slag plays an important role in pyrometallurgical processes to obtain optimum fluxing conditions and operating temperatures.The smelting reduction of titanomagnetite and ilmenite ores in an iron blast furnace(BF)can form Ti(C,N)particles,causing the increased viscosities of slag and hot metal.HIsmelt has been developed in recent years for ironmaking and does not need coke and sinter.The formation of Ti(C,N)in the HIsmelt process is avoided because the oxygen partial pressure in the process is higher than that in the BF.The smelting of TiO_(2)-containing ores in the HIsmelt process results in Al_(2)O_(3)-MgO-SiO_(2)-CaO-TiO_(2)slag.Phase equilibrium in this slag system has been investigated using equilibration,quenching,and electron probe microanalysis techniques.The experimental results were presented in two pseudo-binary sections,which represent the process of HIsmelt for the treatment of 100%titanomagnetite ore and mixed titanomagnetite+ilmenite ore(mass ratio of 2:1),respectively.The primary phases observed in the composition range investigated include pseudo-brookite M_(3)O_(5)(MgO·2TiO_(2)-Al_(2)O_(3)·TiO_(2)),spinel(MgO·Al_(2)O_(3)),perovskite CaTiO_(3),and rutile TiO_(2).The results show that the liquidus temperatures decrease in the TiO_(2)and M_(3)O_(5) primary phase fields and increase in the spinel and CaTiO_(3)primary phase fields with the increase in CaO concentration.The calculation of solid-phase fractions from the experimental data has been demonstrated.The effect of basicity on the liquidus temperatures of the slag has been discussed.The smelting of titanomagnetite plus ilmenite ores has significant advantages to obtain low-sulfur hot metal and high-TiO_(2)slag.Experimentally determined liquidus temperatures were compared with the FactSage predictions to evaluate the existing thermodynamic databases.展开更多
Olive (Olea europaea L.) tree is one of the most extensive and important agricultural crop in Mediterranean countries due to its beneficial health and nutritional properties and its high economic value. Currently, oli...Olive (Olea europaea L.) tree is one of the most extensive and important agricultural crop in Mediterranean countries due to its beneficial health and nutritional properties and its high economic value. Currently, olive tree constitutes the sixth most important cultivated plant in the world, spreading from the Mediterranean region of origin to new production areas such as Australia, South and North America and South Africa. However, the mobilization processes of storage materials i.e. reserve proteins during seed germination, which are largely involved in essential physiological process including plant growth and development, remain poorly understood. Morphometric and immunohistochemistry analyses of protein bodies contained in olive seed storage tissues, cotyledon and endosperm, were performed by using different microscopy techniques, including light (bright-field and fluorescence) microscopy and transmission electron microscopy. Furthermore, we used legumin-like proteins (11S-type globulins) as a molecular marker to study the mobilization of reserve proteins from PBs of cotyledons at germinating seedling stages by using immunofluorescence assays. Results demonstrated that cotyledon and endosperm are characterized by distinct PBs populations containing legumin-like proteins, distinctly discriminated by the number of PBs per cell and tissue, size, immunofluorescence and histochemical staining. These features reflect differential PBs biogenesis during development and maturation processes in olive seed tissues endosperm and cotyledon, in relation to proteins (polypeptides) final composition, SSPs processing and/or packaging during seed maturation. Three different mobilization patterns of legumin-like proteins were identified for the first time in cotyledon PBs during seedling germinating process. Mature proteins composition and/or processing, cell types and enzyme composition and/or differential activation have been discussed as key features determining how proteins mobilize from PBs for further degradation in the cotyledon.展开更多
The effect of dust accumulation on CST (concentrated solar thermal) reflectors is to deflect, or scatter, incident light rays missing the receiver with a subsequent power produced loss. Dust fouling is site specific...The effect of dust accumulation on CST (concentrated solar thermal) reflectors is to deflect, or scatter, incident light rays missing the receiver with a subsequent power produced loss. Dust fouling is site specific, and the understanding of interactions between different weather and or environmental parameters is crucial for plant profitability. This research intends to provide useful insights on the interaction between the most relevant weather parameters affecting soil accumulation. Results show a significant dependency of dust concentration versus humidity and ambient temperature, as well as a nexus between wind speed and ambient temperature seems to exist. As long as the temperature decreases an increase of humidity and dust concentration occurs. This phenomenon takes place mostly overnight till the first hours of the morning. Therefore, mirror's reflectance looks extremely affected by dust accumulation because of high humidity rate during the night and dews of early morning. Further investigations are required to validate the hypothesis that, a more effective cleaning activitie to restore plants' reflectivity are to be carried out during the early morning.展开更多
Objective General practice receptionists provide an essential function in the healthcare system but routinely encounter acts of incivility and aggression from patients,including hostility,abuse and violence.This study...Objective General practice receptionists provide an essential function in the healthcare system but routinely encounter acts of incivility and aggression from patients,including hostility,abuse and violence.This study was conducted to summarise what is known about patient-initiated aggression towards general practice receptionists,including impacts on reception staff and existing mitigation strategies.Design Systematic review with convergent integrated synthesis.Eligibility criteria Studies published at any time in English that examine patient aggression experiences of reception staff in primary care settings.Information sources Searches of five major databases were performed(CINAHL Complete,Scopus,PubMed,Healthcare Administration Database and Google Scholar)to August 2022.Results Twenty studies of various designs were included,ranging from the late 1970s to 2022 and originating from five OECD countries.Twelve were assessed as high quality using a validated checklist.Reviewed articles represented 4107 participants;21.5%were general practice receptionists.All studies reported that displays of aggression towards receptionists by patients were a frequent and routine occurrence in general practice,particularly verbal abuse such as shouting,cursing,accusations of malicious behaviour and use of racist,ablest and sexist insults.Although infrequent,physical violence was widely reported.Inefficient appointment scheduling systems,delayed access to doctors and prescription denial appeared common precipitators.Receptionists adapted their behaviour and demeanour to placate and please patients to avoid escalation of patient frustrations at the cost of their own well-being and clinic productivity.Training in patient aggression management increased receptionist confidence and appeared to decrease negative sequalae.Coordinated support for general practice reception staff who had experienced patient aggression was generally lacking,with a small proportion receiving professional counselling.Conclusions Patient aggression towards reception staff is a serious workplace safety concern for general practices and negatively affects healthcare sector function more broadly.Receptionists in general practice deserve evidence-based measures to improve their working conditions and well-being for their own benefit and that of the community.Registration Pre-registered in Open Science Framework(osf.io/42p85).展开更多
In the endeavor to maximize the refinement effect of primary Si and alleviate the inherent brittleness of hypereutectic Al-Si alloy,the approach of coating P as a modifier on powder was adopted.The ultimate aim was to...In the endeavor to maximize the refinement effect of primary Si and alleviate the inherent brittleness of hypereutectic Al-Si alloy,the approach of coating P as a modifier on powder was adopted.The ultimate aim was to create more heterogeneous fine Al P nucleus and enhance the nucleation efficiency of primary Si on Al P to refine the coarse primary Si to nano-scale during 3D printing.In the combination of large undercooling and high density of nucleation sites,the size of primary Si was successfully refined to 200–300 nm and the divorced eutectic was also induced to modify the microstructure of matrix.In the presence of nano-scale primary Si,the melting pool boundary(MPB)feature disappeared and the fracture mechanism also changed from load transfer to interfacial fracture.Compared with the pristine alloy,the ductility was increased four times without significantly changing the ultimate tensile strength(UTS)and wear resistance.The improvement of ductility is attributed to the refinement of primary Si,the disappearance of MPB features and the formation of divorced eutectic.The optimal tensile properties were:UTS-482 MPa,yield strength-320 MPa and ductility of 8.1%at 0.05 wt.%P.These are comparable to those for high-strength Al alloys.展开更多
文摘Background: Smoking continues to be one of the most popular recreational practices despite its known harmful effects. Aim: The purpose of this survey was to assess the prevalence of smoking in the Caribbean and the correlation of smoking with the disease states of high blood pressure, diabetes and high cholesterol whose risk is known to be higher among smokers. Findings: Our study found a smoking prevalence of 22% in the population, similar to that reported by the World Health Organization (20%) and a positive correlation between smoking and diabetes. Conclusion: The survey shows that smoking numbers within the population are still high and that smoking increases the risk of certain disease states within smokers. Aggressive global efforts to reduce smoking should continue so as to minimize the negative impact of smoking on health.
基金RSL Queensland funded this study as part of the PTSD Initiative at the Gallipoli Medical Research Foundation.The Australian Government Department of Veterans’Affairs provided transport for eligible participants。
文摘Background:Posttraumatic stress disorder(PTSD)has been associated with volumetric and white matter microstructural changes among general and veteran populations.However,regions implicated have greatly varied and often conflict between studies,potentially due to confounding comorbidities within samples.This study compared grey matter volume and white matter microstructure among Australian combat veterans with and without a lifetime diagnosis of PTSD,in a homogenous sample assessed for known confounding comorbidities.Methods:Sixty-eight male trauma-exposed veterans(16 PTSD-diagnosed;mean age 69 years)completed a battery of psychometric assessments and underwent magnetic resonance and diffusion tensor imaging.Analyses included tractbased spatial statistics,voxel-wise analyses,diffusion connectome-based group-wise analysis,and volumetric analysis.Results:Significantly smaller grey matter volumes were observed in the left prefrontal cortex(P=0.026),bilateral middle frontal gyrus(P=0.021),and left anterior insula(P=0.048)in the PTSD group compared to controls.Significant negative correlations were found between PTSD symptom severity and fractional anisotropy values in the left corticospinal tract(R^(2)=0.34,P=0.024)and left inferior cerebellar peduncle(R^(2)=0.62,P=0.016).No connectome-based differences in white matter properties were observed.Conclusions:Findings from this study reinforce reports of white matter alterations,as indicated by reduced fractional anisotropy values,in relation to PTSD symptom severity,as well as patterns of reduced volume in the prefrontal cortex.These results contribute to the developing profile of neuroanatomical differences uniquely attributable to veterans who suffer from chronic PTSD.
文摘We report a phase inversion polymer coating as a novel concept with potential to prevent clay swelling and fines generation in coal seam gas, or other petroleum, wellbores. Our approach uses polyethersulfone (PES) with N-methyl-2- pyrrolidone (NMP) as a water-soluble solvent to form a dense, low-porosity film across the clay-rich interburden layers, but a porous and permeable membrane on coal seams. This contrasting behaviour occurs because the coal contains much more free water than the clay-rich interburden layers. We demonstrate the efficacy of the method to prevent clay spalling in immersion tests and under a flow of fresh water in a visual swell test apparatus. The clay-rich rocks studied were mudstone and siltstone, and these were dip coated in the PES/NMP solution. The uncoated mudstone swelled and broke apart quickly in the immersion test and visual flow test, but the PES coated rock samples were stable for 30 days. The coated rock and coal samples were characterised by X-ray diffraction, Fourier transform infrared spectroscopy and scanning electron microscopy. The morphology of coated mudstone and coated coal samples showed that the polymer formed a dense layer across the low-permeability mudstone, but an open porous structure on the coal surface. The effect of the coating on the permeability of KCl brine through coal was measured in a core-flood apparatus. Although the permeability of the coal showed some deterioration after coating, from (0.58 ± 0.12) mD to (0.3 ±0.03) mD, these results demonstrate the potential of a smart polymer coating to prevent clay swelling while remaining permeable to gas and water on coal layers.
文摘BACKGROUND The presence of small air bubbles and foam are an impediment to a successful colonoscopy. They impair an endoscopist’s view and diminish the diagnostic accuracy of the study. This has been particularly noted to be of concern with the switch to lower volume polyethylene glycol (PEG) and bisacodyl combination preparation. AIM To evaluate the effect of oral simethicone addition to bowel preparation on intraluminal bubbles reduction during colonoscopy. METHODS Described is a prospective, randomized, multi-center, double-blinded, placebocontrolled study to evaluate the use of premixed simethicone formulation with split-regimen, low-volume PEG-bisacodyl combination bowel preparation for 168 outpatients undergoing screening, surveillance, and diagnostic colonoscopies. Primary outcome includes evaluation of bubbles during colonoscopy graded using the Intraluminal Bubbles Scale. Secondary outcomes include evaluation of the Boston Bowel Preparation Scale (BBPS), total number of polyps, polyp size differentiation, polyp laterality, adenoma detection, mass detection, cecal insertion time, withdrawal time, and patient-reported adverse events. RESULTS Higher Intraluminal Bubbles grades III and IV (less than 75% of the mucosa cleared of bubbles/foam requiring intervention with simethicone infused wash) were detected in the placebo group [Simethicone n = 4/84 vs Placebo n = 20/84 (P = 0.007)]. BBPS total score was 7.42 [standard deviation (SD)=± 1.51] in the simethicone group and 7.28 (SD =± 1.44) in the placebo group (P = 0.542) from a total of 9. Significantly higher number of adenomas were detected in the simethicone group (P = 0.001). CONCLUSION The addition of simethicone to bowel preparation is well advised for its antifoaming properties. The results of this study suggest that addition of oral simethicone can improve bowel wall visibility.
文摘The phase equilibrium information of slag plays an important role in pyrometallurgical processes to obtain optimum fluxing conditions and operating temperatures.The smelting reduction of titanomagnetite and ilmenite ores in an iron blast furnace(BF)can form Ti(C,N)particles,causing the increased viscosities of slag and hot metal.HIsmelt has been developed in recent years for ironmaking and does not need coke and sinter.The formation of Ti(C,N)in the HIsmelt process is avoided because the oxygen partial pressure in the process is higher than that in the BF.The smelting of TiO_(2)-containing ores in the HIsmelt process results in Al_(2)O_(3)-MgO-SiO_(2)-CaO-TiO_(2)slag.Phase equilibrium in this slag system has been investigated using equilibration,quenching,and electron probe microanalysis techniques.The experimental results were presented in two pseudo-binary sections,which represent the process of HIsmelt for the treatment of 100%titanomagnetite ore and mixed titanomagnetite+ilmenite ore(mass ratio of 2:1),respectively.The primary phases observed in the composition range investigated include pseudo-brookite M_(3)O_(5)(MgO·2TiO_(2)-Al_(2)O_(3)·TiO_(2)),spinel(MgO·Al_(2)O_(3)),perovskite CaTiO_(3),and rutile TiO_(2).The results show that the liquidus temperatures decrease in the TiO_(2)and M_(3)O_(5) primary phase fields and increase in the spinel and CaTiO_(3)primary phase fields with the increase in CaO concentration.The calculation of solid-phase fractions from the experimental data has been demonstrated.The effect of basicity on the liquidus temperatures of the slag has been discussed.The smelting of titanomagnetite plus ilmenite ores has significant advantages to obtain low-sulfur hot metal and high-TiO_(2)slag.Experimentally determined liquidus temperatures were compared with the FactSage predictions to evaluate the existing thermodynamic databases.
文摘Olive (Olea europaea L.) tree is one of the most extensive and important agricultural crop in Mediterranean countries due to its beneficial health and nutritional properties and its high economic value. Currently, olive tree constitutes the sixth most important cultivated plant in the world, spreading from the Mediterranean region of origin to new production areas such as Australia, South and North America and South Africa. However, the mobilization processes of storage materials i.e. reserve proteins during seed germination, which are largely involved in essential physiological process including plant growth and development, remain poorly understood. Morphometric and immunohistochemistry analyses of protein bodies contained in olive seed storage tissues, cotyledon and endosperm, were performed by using different microscopy techniques, including light (bright-field and fluorescence) microscopy and transmission electron microscopy. Furthermore, we used legumin-like proteins (11S-type globulins) as a molecular marker to study the mobilization of reserve proteins from PBs of cotyledons at germinating seedling stages by using immunofluorescence assays. Results demonstrated that cotyledon and endosperm are characterized by distinct PBs populations containing legumin-like proteins, distinctly discriminated by the number of PBs per cell and tissue, size, immunofluorescence and histochemical staining. These features reflect differential PBs biogenesis during development and maturation processes in olive seed tissues endosperm and cotyledon, in relation to proteins (polypeptides) final composition, SSPs processing and/or packaging during seed maturation. Three different mobilization patterns of legumin-like proteins were identified for the first time in cotyledon PBs during seedling germinating process. Mature proteins composition and/or processing, cell types and enzyme composition and/or differential activation have been discussed as key features determining how proteins mobilize from PBs for further degradation in the cotyledon.
文摘The effect of dust accumulation on CST (concentrated solar thermal) reflectors is to deflect, or scatter, incident light rays missing the receiver with a subsequent power produced loss. Dust fouling is site specific, and the understanding of interactions between different weather and or environmental parameters is crucial for plant profitability. This research intends to provide useful insights on the interaction between the most relevant weather parameters affecting soil accumulation. Results show a significant dependency of dust concentration versus humidity and ambient temperature, as well as a nexus between wind speed and ambient temperature seems to exist. As long as the temperature decreases an increase of humidity and dust concentration occurs. This phenomenon takes place mostly overnight till the first hours of the morning. Therefore, mirror's reflectance looks extremely affected by dust accumulation because of high humidity rate during the night and dews of early morning. Further investigations are required to validate the hypothesis that, a more effective cleaning activitie to restore plants' reflectivity are to be carried out during the early morning.
基金This project was supported by Healthy Primary Care Team(Griffith University)and the Centre for Community Health and Wellbeing(University of Queensland)At the time of this project,LB's salary was supported by an NHMRC grant(APP1173496).
文摘Objective General practice receptionists provide an essential function in the healthcare system but routinely encounter acts of incivility and aggression from patients,including hostility,abuse and violence.This study was conducted to summarise what is known about patient-initiated aggression towards general practice receptionists,including impacts on reception staff and existing mitigation strategies.Design Systematic review with convergent integrated synthesis.Eligibility criteria Studies published at any time in English that examine patient aggression experiences of reception staff in primary care settings.Information sources Searches of five major databases were performed(CINAHL Complete,Scopus,PubMed,Healthcare Administration Database and Google Scholar)to August 2022.Results Twenty studies of various designs were included,ranging from the late 1970s to 2022 and originating from five OECD countries.Twelve were assessed as high quality using a validated checklist.Reviewed articles represented 4107 participants;21.5%were general practice receptionists.All studies reported that displays of aggression towards receptionists by patients were a frequent and routine occurrence in general practice,particularly verbal abuse such as shouting,cursing,accusations of malicious behaviour and use of racist,ablest and sexist insults.Although infrequent,physical violence was widely reported.Inefficient appointment scheduling systems,delayed access to doctors and prescription denial appeared common precipitators.Receptionists adapted their behaviour and demeanour to placate and please patients to avoid escalation of patient frustrations at the cost of their own well-being and clinic productivity.Training in patient aggression management increased receptionist confidence and appeared to decrease negative sequalae.Coordinated support for general practice reception staff who had experienced patient aggression was generally lacking,with a small proportion receiving professional counselling.Conclusions Patient aggression towards reception staff is a serious workplace safety concern for general practices and negatively affects healthcare sector function more broadly.Receptionists in general practice deserve evidence-based measures to improve their working conditions and well-being for their own benefit and that of the community.Registration Pre-registered in Open Science Framework(osf.io/42p85).
基金financially supported by the National Key Research and Development Program of China(No.2018YFB1105100)the Scientific Instrument Developing Project of the Chinese Academy of Sciences(No.YJKYYQ20190011)。
文摘In the endeavor to maximize the refinement effect of primary Si and alleviate the inherent brittleness of hypereutectic Al-Si alloy,the approach of coating P as a modifier on powder was adopted.The ultimate aim was to create more heterogeneous fine Al P nucleus and enhance the nucleation efficiency of primary Si on Al P to refine the coarse primary Si to nano-scale during 3D printing.In the combination of large undercooling and high density of nucleation sites,the size of primary Si was successfully refined to 200–300 nm and the divorced eutectic was also induced to modify the microstructure of matrix.In the presence of nano-scale primary Si,the melting pool boundary(MPB)feature disappeared and the fracture mechanism also changed from load transfer to interfacial fracture.Compared with the pristine alloy,the ductility was increased four times without significantly changing the ultimate tensile strength(UTS)and wear resistance.The improvement of ductility is attributed to the refinement of primary Si,the disappearance of MPB features and the formation of divorced eutectic.The optimal tensile properties were:UTS-482 MPa,yield strength-320 MPa and ductility of 8.1%at 0.05 wt.%P.These are comparable to those for high-strength Al alloys.