Hadrons made by diquark-antidiquark pairs(tetraquarks)are held together by QCD forces in an overall color singlet.As stated in the original proposals and similarly to baryons and qq mesons,tetraquarks form complete mu...Hadrons made by diquark-antidiquark pairs(tetraquarks)are held together by QCD forces in an overall color singlet.As stated in the original proposals and similarly to baryons and qq mesons,tetraquarks form complete multiplets of the flavour symmetry,SU(3)f.展开更多
We reanalyze the recent computation of the amplitude of the Higgs boson decay into two photons presented by Gastmans et al. [1, 2]. The reasons for why this result cannot be the correct one have been discussed in some...We reanalyze the recent computation of the amplitude of the Higgs boson decay into two photons presented by Gastmans et al. [1, 2]. The reasons for why this result cannot be the correct one have been discussed in some recent papers. We address here the general issue of the indeterminacy of integrals with four-dimensional gauge-breaking regulators and to which extent it might eventually be solved by imposing physical constraints. Imposing gauge invariance as the last step upon Rξ-gauge calculations with four-dimensional gauge-breaking regulators, allows us to recover the well known H→γγ result. However we show that in the particular case of the unitary gauge, the indeterminacy cannot be tackled in the same way. The combination of the unitary gauge with a cutoff regularization scheme turns out to be non-predictive.展开更多
The association between nicotine dependence and affective disorders, particularly major depressive disorder (MDD), is well known with high prevalence rates being reported for smokers. The reason for this association i...The association between nicotine dependence and affective disorders, particularly major depressive disorder (MDD), is well known with high prevalence rates being reported for smokers. The reason for this association is not clear, but, it has been argued that smoking may help individuals to cope with stress or medicate depressed mood. Smoking cessation programs are useful in helping smokers to quit, but smoking is a very difficult addiction to break, especially for people suffering from depression, and the need for novel and effective approaches to smoking cessation interventions for this special population is unquestionable. The e-cigarette is a battery-powered electronic nicotine delivery device (ENDD), which may help smokers to remain abstinent during their quit attempt. Here, we report for the first time objective measures of smoking cessation in two heavy smokers, suffering from depression, who experimented the e-cigarette.展开更多
The problem of understanding loosely bound hadron molecules prompt production at hadron colliders is still open: how is it possible that meson molecules with binding energy compatible with zero could be formed within ...The problem of understanding loosely bound hadron molecules prompt production at hadron colliders is still open: how is it possible that meson molecules with binding energy compatible with zero could be formed within the bulk of the hadrons ejected in very high energy collisions? Monte Carlo simulations have been performed in the literature, leading to production cross sections, two orders of magnitude which were smaller than the experimental value. One possible mechanism to reduce this gap could be final state interactions of heavy mesons, but a precise evaluation of such effect is challenged by the presence of pions between the molecular constituents. In this paper, we present a new mechanism by using precisely such comoving pions. Heavy meson pairs can indeed slow down because of elastic scattering with surrounding pions. The number of low-relative-momentum meson pairs increases, thereby enhancing prompt production cross section. In this preliminar simulation, we show that an enhancement of 100 is indeed possible.展开更多
The purpose of this scoping review is to create a single narrative that describes the impact of smoking cessation on metabolic parameters in people with diabetes.It is generally well accepted that smoking enhances the...The purpose of this scoping review is to create a single narrative that describes the impact of smoking cessation on metabolic parameters in people with diabetes.It is generally well accepted that smoking enhances the harmful effects of elevated blood glucose levels,accelerating the vascular damage seen in patients with diabetes.Smoking cessation has clear benefits in terms of reducing cardiovascular morbidity and mortality.However,there is less evidence for the impact of smoking cessation on other diabetes-related complications.Studies in people with diabetes have shown improvement as well as temporary deterioration in glycemic control after ceasing smoking.Only a few studies have described the effect of quitting smoking on insulin resistance and lipid parameters,however,their results have been inconclusive.In this situation,healthcare professionals should not assume that cessation of smoking will improve metabolic parameters in patients with diabetes.It seems they should, first of all, emphasize the prevention of weight gain that may be associatedwith quitting smoking. The lack of data regarding the metabolic effects of smoking and smokingcessation in diabetes is very disappointing and this area needs to be addressed.展开更多
Background:Zellweger spectrum disorder(ZSD)is an autosomal recessive disease caused by mutations in any one of 13 PEX genes whose protein products are required for peroxisome assembly.Retinopathy leading to blindness ...Background:Zellweger spectrum disorder(ZSD)is an autosomal recessive disease caused by mutations in any one of 13 PEX genes whose protein products are required for peroxisome assembly.Retinopathy leading to blindness is one of the major untreatable handicaps faced by patients with ZSD but is not well characterized,and the requirement for peroxisomes in retinal health is unknown.To address this and to inform future therapeutic studies,we examined the progression of retinopathy in our murine model for the common PEX1-G843D allele.Methods:Retinal electrophysiology(ffERG)and histology were performed in a cohort of Pex1-G844D(equivalent to human G843D)mice from 2 to 32 wks.Visual acuity was assessed using optokinetics.The levels of PEX1-G843D protein,its binding partner Pex6,and its putative ligand Pex5(the peroxisome enzyme receptor)in the retina were determined by immunoblotting.Peroxisome biochemical metabolites in the whole eye and retina were measured using LC/MSMS.Retinal immunohistochemistry was used to visualize various cell types.Results:Cone ffERG response in the mutants remained residual(5%that of control)regardless of age.Maximal rod-mediated responses(50-70%of control)was reached at 4-6 wks,and then progressively decreased with age.B-waves were affected more severely than a-waves,while high frequency ERG components(oscillatory potentials)are better preserved than low frequency components(a-and b-waves).Visual evoked potential was diminished at 32 weeks.Assessment of visual acuity using optokinetics showed low visual reflexes by 11-13 weeks of age.We found normal amounts of Pex1-G844D,Pex6,and Pex5 protein in retina,suggesting that the mutated protein is not degraded.Measurement of peroxisome metabolites showed elevated very long chain fatty acids(VLCFA)and decreased plasmalogens in the whole eye,indicative of peroxisome dysfunction.In the retina,VLCFAs were not elevated,and only C22:6(docosahexaenoic acid)was decreased of the plasmalogens measured.There were normal amounts and localization of Pex1-G844D a展开更多
Background:Oxygen therapy provided to support the lungs of premature newborns often leads to damages to the retina called retinopathy of prematurity(ROP)and long-term visual impairments.Current treatments for ROP are ...Background:Oxygen therapy provided to support the lungs of premature newborns often leads to damages to the retina called retinopathy of prematurity(ROP)and long-term visual impairments.Current treatments for ROP are invasive and aim at preventing further progression of the damages to the retina,but do not repair these damages.Our goal is to investigate the therapeutic effect of sildenafil on retinal structure in a rat model of ROP.Methods:Sprague-Dawley rats were exposed to hyperoxia(i.e.,80%oxygen)interrupted by three 0.5-hour periods of normoxia(i.e.,21%oxygen)(hyperoxic animals)per day or room air only(i.e.,21%oxygen)(control animals)from post-natal day 4(P4)to 14(P14).Pups were then housed in room air.Sildenafil(50 mg/kg)or vehicle was given per os twice daily after oxygen exposure(from P15 to P21).At P30,retinas were extracted,and sectioned.For retinal histology,eyes were stained with toluidine blue to measure the thicknesses of the different retinal layers.Immunohistochemistry was also performed to count the number of retinal ganglion cells and bipolar cells in the inner retina,as well as the number of astrocytes and microglia within the different retinal layers.Results:Hyperoxia caused a reduction in thickness of the outer plexiform layer(OPL)and a decrease in the number of bipolar cells in some parts of the retina,compared to control animals(P<0.05);in addition,the number of microglia cells was significantly increased in the rats exposed to hyperoxia,compared to controls(P<0.05).Sildenafil improved OPL thickness in ROP animals,but did not change the number of bipolar cells.In hyperoxic rats treated with sildenafil,the number of microglia were similar to control rats.The number of retinal ganglion cells and astrocytes did not differ significantly between the groups.Conclusions:Treatment with sildenafil following oxygen exposure provided some recovery of the structure of the retina.This beneficial effect may be modulated by a decrease of inflammation within the retina.展开更多
Background:Zellweger spectrum disorder(ZSD)is an autosomal recessive disease caused by mutations in any one of 13 PEX genes whose protein products are required for peroxisome assembly.Retinopathy leading to blindness ...Background:Zellweger spectrum disorder(ZSD)is an autosomal recessive disease caused by mutations in any one of 13 PEX genes whose protein products are required for peroxisome assembly.Retinopathy leading to blindness is one of the major handicaps faced by affected individuals,but treatment for this is supportive only.To test whether we could improve visual function in ZSD,we performed a proof-of-concept trial for PEX1 gene augmentation therapy using the Pex1-G844D mouse model,which bears the equivalent to a common human mutation.This model exhibits a gradual decline in scotopic ffERG response,an always residual photopic ffERG response,diminished visual acuity,and cone and bipolar cell anomalies.Methods:We administered subretinal injections of a PEX1-containing viral vector(AAV8.CMV.hPEX1.HA)to 2 mouse cohorts of 5 or 9 weeks of age.A GFP-containing vector was used as a control in the contralateral eye of each animal.Efficient expression of the virus was confirmed by retinal histology/immunohistochemistry,and its ability to recover peroxisome import was confirmed in vitro.Preliminary ffERG and optokinetic(OKN)analyses were performed on a subset of animals at 8,16,and 20 weeks after gene delivery.Final ffERG and OKN measures were performed when each cohort reached 32 weeks of age(23 or 27 weeks post injection).Results:Preliminary ffERG and OKN analyses at 8 weeks post injection showed mildly better retinal response and visual acuity,respectively,in the PEX1-injected eyes,as did ffERG analysis when each cohort reached 25 weeks of age(16 or 20 weeks after gene delivery).This effect was more pronounced in the cohort treated at 5 weeks of age,when ffERG response is highest in Pex1-G844D mice.At 32 weeks of age,the ffERG response in the PEX1-injected eyes was double that of GFP-injected eyes,on average,though there was no change in OKN.Furthermore,in PEX1-injected eyes the photopic ffERG response improved over time,and the decline in scotopic b-wave amplitude was ameliorated compared to un-injected eyes.Conclusions:AAV8展开更多
文摘Hadrons made by diquark-antidiquark pairs(tetraquarks)are held together by QCD forces in an overall color singlet.As stated in the original proposals and similarly to baryons and qq mesons,tetraquarks form complete multiplets of the flavour symmetry,SU(3)f.
文摘We reanalyze the recent computation of the amplitude of the Higgs boson decay into two photons presented by Gastmans et al. [1, 2]. The reasons for why this result cannot be the correct one have been discussed in some recent papers. We address here the general issue of the indeterminacy of integrals with four-dimensional gauge-breaking regulators and to which extent it might eventually be solved by imposing physical constraints. Imposing gauge invariance as the last step upon Rξ-gauge calculations with four-dimensional gauge-breaking regulators, allows us to recover the well known H→γγ result. However we show that in the particular case of the unitary gauge, the indeterminacy cannot be tackled in the same way. The combination of the unitary gauge with a cutoff regularization scheme turns out to be non-predictive.
基金This material is based upon work supported in part by the U.S.Department of Energy,Office of Science,Office of Nuclear Physics(DE-AC05-06OR23177)the U.S.Department of Energy,Office of Science,(DE-SC0009919)
文摘We briefly comment on the paper by Albaladejo et al., Chinese Phys. C 41 121001, rejecting its conclusions.
文摘The association between nicotine dependence and affective disorders, particularly major depressive disorder (MDD), is well known with high prevalence rates being reported for smokers. The reason for this association is not clear, but, it has been argued that smoking may help individuals to cope with stress or medicate depressed mood. Smoking cessation programs are useful in helping smokers to quit, but smoking is a very difficult addiction to break, especially for people suffering from depression, and the need for novel and effective approaches to smoking cessation interventions for this special population is unquestionable. The e-cigarette is a battery-powered electronic nicotine delivery device (ENDD), which may help smokers to remain abstinent during their quit attempt. Here, we report for the first time objective measures of smoking cessation in two heavy smokers, suffering from depression, who experimented the e-cigarette.
文摘The problem of understanding loosely bound hadron molecules prompt production at hadron colliders is still open: how is it possible that meson molecules with binding energy compatible with zero could be formed within the bulk of the hadrons ejected in very high energy collisions? Monte Carlo simulations have been performed in the literature, leading to production cross sections, two orders of magnitude which were smaller than the experimental value. One possible mechanism to reduce this gap could be final state interactions of heavy mesons, but a precise evaluation of such effect is challenged by the presence of pions between the molecular constituents. In this paper, we present a new mechanism by using precisely such comoving pions. Heavy meson pairs can indeed slow down because of elastic scattering with surrounding pions. The number of low-relative-momentum meson pairs increases, thereby enhancing prompt production cross section. In this preliminar simulation, we show that an enhancement of 100 is indeed possible.
基金Department of Clinical and Experimental Medicine of the University of Catania,No.6C813202024/1_3_02_07_01/2020。
文摘The purpose of this scoping review is to create a single narrative that describes the impact of smoking cessation on metabolic parameters in people with diabetes.It is generally well accepted that smoking enhances the harmful effects of elevated blood glucose levels,accelerating the vascular damage seen in patients with diabetes.Smoking cessation has clear benefits in terms of reducing cardiovascular morbidity and mortality.However,there is less evidence for the impact of smoking cessation on other diabetes-related complications.Studies in people with diabetes have shown improvement as well as temporary deterioration in glycemic control after ceasing smoking.Only a few studies have described the effect of quitting smoking on insulin resistance and lipid parameters,however,their results have been inconclusive.In this situation,healthcare professionals should not assume that cessation of smoking will improve metabolic parameters in patients with diabetes.It seems they should, first of all, emphasize the prevention of weight gain that may be associatedwith quitting smoking. The lack of data regarding the metabolic effects of smoking and smokingcessation in diabetes is very disappointing and this area needs to be addressed.
文摘Background:Zellweger spectrum disorder(ZSD)is an autosomal recessive disease caused by mutations in any one of 13 PEX genes whose protein products are required for peroxisome assembly.Retinopathy leading to blindness is one of the major untreatable handicaps faced by patients with ZSD but is not well characterized,and the requirement for peroxisomes in retinal health is unknown.To address this and to inform future therapeutic studies,we examined the progression of retinopathy in our murine model for the common PEX1-G843D allele.Methods:Retinal electrophysiology(ffERG)and histology were performed in a cohort of Pex1-G844D(equivalent to human G843D)mice from 2 to 32 wks.Visual acuity was assessed using optokinetics.The levels of PEX1-G843D protein,its binding partner Pex6,and its putative ligand Pex5(the peroxisome enzyme receptor)in the retina were determined by immunoblotting.Peroxisome biochemical metabolites in the whole eye and retina were measured using LC/MSMS.Retinal immunohistochemistry was used to visualize various cell types.Results:Cone ffERG response in the mutants remained residual(5%that of control)regardless of age.Maximal rod-mediated responses(50-70%of control)was reached at 4-6 wks,and then progressively decreased with age.B-waves were affected more severely than a-waves,while high frequency ERG components(oscillatory potentials)are better preserved than low frequency components(a-and b-waves).Visual evoked potential was diminished at 32 weeks.Assessment of visual acuity using optokinetics showed low visual reflexes by 11-13 weeks of age.We found normal amounts of Pex1-G844D,Pex6,and Pex5 protein in retina,suggesting that the mutated protein is not degraded.Measurement of peroxisome metabolites showed elevated very long chain fatty acids(VLCFA)and decreased plasmalogens in the whole eye,indicative of peroxisome dysfunction.In the retina,VLCFAs were not elevated,and only C22:6(docosahexaenoic acid)was decreased of the plasmalogens measured.There were normal amounts and localization of Pex1-G844D a
文摘Background:Oxygen therapy provided to support the lungs of premature newborns often leads to damages to the retina called retinopathy of prematurity(ROP)and long-term visual impairments.Current treatments for ROP are invasive and aim at preventing further progression of the damages to the retina,but do not repair these damages.Our goal is to investigate the therapeutic effect of sildenafil on retinal structure in a rat model of ROP.Methods:Sprague-Dawley rats were exposed to hyperoxia(i.e.,80%oxygen)interrupted by three 0.5-hour periods of normoxia(i.e.,21%oxygen)(hyperoxic animals)per day or room air only(i.e.,21%oxygen)(control animals)from post-natal day 4(P4)to 14(P14).Pups were then housed in room air.Sildenafil(50 mg/kg)or vehicle was given per os twice daily after oxygen exposure(from P15 to P21).At P30,retinas were extracted,and sectioned.For retinal histology,eyes were stained with toluidine blue to measure the thicknesses of the different retinal layers.Immunohistochemistry was also performed to count the number of retinal ganglion cells and bipolar cells in the inner retina,as well as the number of astrocytes and microglia within the different retinal layers.Results:Hyperoxia caused a reduction in thickness of the outer plexiform layer(OPL)and a decrease in the number of bipolar cells in some parts of the retina,compared to control animals(P<0.05);in addition,the number of microglia cells was significantly increased in the rats exposed to hyperoxia,compared to controls(P<0.05).Sildenafil improved OPL thickness in ROP animals,but did not change the number of bipolar cells.In hyperoxic rats treated with sildenafil,the number of microglia were similar to control rats.The number of retinal ganglion cells and astrocytes did not differ significantly between the groups.Conclusions:Treatment with sildenafil following oxygen exposure provided some recovery of the structure of the retina.This beneficial effect may be modulated by a decrease of inflammation within the retina.
文摘Background:Zellweger spectrum disorder(ZSD)is an autosomal recessive disease caused by mutations in any one of 13 PEX genes whose protein products are required for peroxisome assembly.Retinopathy leading to blindness is one of the major handicaps faced by affected individuals,but treatment for this is supportive only.To test whether we could improve visual function in ZSD,we performed a proof-of-concept trial for PEX1 gene augmentation therapy using the Pex1-G844D mouse model,which bears the equivalent to a common human mutation.This model exhibits a gradual decline in scotopic ffERG response,an always residual photopic ffERG response,diminished visual acuity,and cone and bipolar cell anomalies.Methods:We administered subretinal injections of a PEX1-containing viral vector(AAV8.CMV.hPEX1.HA)to 2 mouse cohorts of 5 or 9 weeks of age.A GFP-containing vector was used as a control in the contralateral eye of each animal.Efficient expression of the virus was confirmed by retinal histology/immunohistochemistry,and its ability to recover peroxisome import was confirmed in vitro.Preliminary ffERG and optokinetic(OKN)analyses were performed on a subset of animals at 8,16,and 20 weeks after gene delivery.Final ffERG and OKN measures were performed when each cohort reached 32 weeks of age(23 or 27 weeks post injection).Results:Preliminary ffERG and OKN analyses at 8 weeks post injection showed mildly better retinal response and visual acuity,respectively,in the PEX1-injected eyes,as did ffERG analysis when each cohort reached 25 weeks of age(16 or 20 weeks after gene delivery).This effect was more pronounced in the cohort treated at 5 weeks of age,when ffERG response is highest in Pex1-G844D mice.At 32 weeks of age,the ffERG response in the PEX1-injected eyes was double that of GFP-injected eyes,on average,though there was no change in OKN.Furthermore,in PEX1-injected eyes the photopic ffERG response improved over time,and the decline in scotopic b-wave amplitude was ameliorated compared to un-injected eyes.Conclusions:AAV8
