We report the discovery of PSR J1909+0122 by the Five-hundred-meter Aperture Spherical Radio Telescope(FAST)as part of the Commensal Radio Astronomy FAST Survey.PSR J1909+0122 has a spin period of 1.257 s and a disper...We report the discovery of PSR J1909+0122 by the Five-hundred-meter Aperture Spherical Radio Telescope(FAST)as part of the Commensal Radio Astronomy FAST Survey.PSR J1909+0122 has a spin period of 1.257 s and a dispersion measure of 186.2 pc cm^(-3).The averaged pulse profile shows two distinct components.We performed a single-pulse study based on a one-hour observation at 1.25 GHz on 2021 August 23.We used a threshold of 5σ_(ep) to measure the nulling fraction(NF)as 63%±1.5%.The longitude-resolved fluctuation spectra and fast Fourier transform spectra of the binary sequences revealed the quasi-periodicity of nulling with a period of 30 rotation periods.We examined the reliability of the periodicity by comparing it to random noise injection.The NF,E,and modulation periodicity P_(M) of PSR J1909+0122 were compared with other periodic nulling pulsars,showing that the source of J1909+0122 has the second largest NF in the population.Long-term timing observations over six months were used to derive the phase-connected ephemeris of this pulsar.The measured P and P values disfavor dipolar geometry for polar gap models,and the prediction for a space-charge-limited flow model in the case of inverse Compton scattering is only just above the death line.In this work,PSR J1909+0122 has revealed possible correlations between nulling behavior and pulsar properties,which will help to shed light on the pulsar emission mechanism and its temporal evolution in future observations.展开更多
Carbon dioxide (CO<sub>2</sub>) is one of the most important greenhouse gases;its concentration and distribution have important implications on climate change. The El Ni?o Southern Oscillation (ENSO) is th...Carbon dioxide (CO<sub>2</sub>) is one of the most important greenhouse gases;its concentration and distribution have important implications on climate change. The El Ni?o Southern Oscillation (ENSO) is the Earth’s strongest climate fluctuation on inter-annual time scales and has global impacts. However, to date, there is no research on how ENSO affects the spatial distribution of CO<sub>2</sub> concentration. In this study, we used spatial CO<sub>2</sub> data from the ENVIronmentSATellite (ENVISAT) and the Greenhouse Gases Observing Satellite (GOSAT), the long duration monthly mean atmospheric CO<sub>2</sub> from Mauna Loa Observatory, Multivariate ENSO Index (MEI) from Earth System Research Laboratory to analyze the way that ENSO affects spatial distribution of CO<sub>2</sub> concentration in South America, which is affected by ENSO seriously. Our research revealed that monthly CO<sub>2</sub> growth rate has a moderate, positive correlation relationship with MEI. We used geostatistics to predict and simulate the spatial distribution of CO<sub>2</sub> and found that in south of 12°S, CO<sub>2</sub> concentration of ENSO warm episode is lower than the one of ENSO cold and neutral episodes. ENSO impacts CO<sub>2</sub> spatial distribution mainly in November, December, January and February;moderate-high concentration zone of ENSO warm episode more concentrates in the northern part of South America.展开更多
Penile reconstruction following cancer resection has long been a challenge due to demand for both aesthetic and functional preservation. Although various methods have attempted to achieve both goals, none have succeed...Penile reconstruction following cancer resection has long been a challenge due to demand for both aesthetic and functional preservation. Although various methods have attempted to achieve both goals, none have succeeded entirely. In this report, we introduce a novel reconstructive technique on a 64-year-old patient with squamous cell carcinoma of the glans penis. The technique consisted of two staged procedures. First, a dermal substitute, consisting of bovine collagen, was sutured onto the defect after partial glansectomy and three weeks later, the integrated dermis was covered with autologous non-meshed partial thickness skin graft. Use of this dermal substitute in a staged fashion allowed for ability to await final pathologic margins prior to definitive reconstruction and increased dermal thickness. After 9-month follow-up, sexual function returned within 3 months and the patient remained healed. We found this technique to be useful in concurrently preserving penile function and cosmesis. Future studies should include more patients and longer follow-up.展开更多
Globular clusters harbor numerous millisecond pulsars,but long-period pulsars(P 100 ms)are rarely found.In this study,we employed a fast folding algorithm to analyze observational data from multiple globular clusters ...Globular clusters harbor numerous millisecond pulsars,but long-period pulsars(P 100 ms)are rarely found.In this study,we employed a fast folding algorithm to analyze observational data from multiple globular clusters obtained by the Five-hundredmeter Aperture Spherical radio Telescope(FAST),aiming to detect the existence of long-period pulsars.We estimated the impact of the median filtering algorithm in eliminating red noise on the minimum detectable flux density(S_(min))of pulsars.Subsequently,we successfully discovered two isolated long-period pulsars in M15 with periods approximately equal to 1.928451 and3.960716 s,respectively.On the P-˙P diagram,both pulsars are positioned below the spin-up line,suggesting a possible history of partial recycling in X-ray binary systems disrupted by dynamical encounters later on.According to timing results,these two pulsars exhibit remarkably strong magnetic fields.If the magnetic fields were weakened during the accretion process,then a short duration of accretion might explain the strong magnetic fields of these pulsars.展开更多
More than 50%of prostate cancer(PCa)patients have bone metastasis with osteo-blastic lesions.MiR-18a-5p is associated with the development and metastasis of PCa,but it remains unclear whether it is involved in osteobl...More than 50%of prostate cancer(PCa)patients have bone metastasis with osteo-blastic lesions.MiR-18a-5p is associated with the development and metastasis of PCa,but it remains unclear whether it is involved in osteoblastic lesions.We first found that miR-18a-5p was highly expressed in the bone microenvironment of patients with PCa bone metastases.To address how miR-18a-5p affects PCa osteoblastic lesions,antagonizing miR-18a-5p in PCa cells or pre-osteoblasts inhibited osteoblast differentiation in vitro.Moreover,injection of PCa cells with miR-18a-5p inhibition improved bone biomechanical properties and bone mineral mass in vivo.Furthermore,miR-18a-5p was transferred to osteoblasts by exosomes derived from PCa cells and targeted the Hist1h2bc gene,resulting in Ctnnb1 up-regulation in the Wnt/β-catenin signaling pathway.Translationally,antagomir-18a-5p significantly improved bone biomechanical properties and alleviated sclerotic lesions from osteoblastic me-tastases in BALB/c nude mice.These data suggest that inhibition of exosome-delivered miR-18a-5p ameliorates PCa-induced osteoblastic lesions.展开更多
We used OCO-2 products and considered three factors that potentially affect CO_(2) concentration in Indonesia:sea surface temperature(SST),forest fires and vegetation.From 2014 to 2016,CO_(2) concentration in Indonesi...We used OCO-2 products and considered three factors that potentially affect CO_(2) concentration in Indonesia:sea surface temperature(SST),forest fires and vegetation.From 2014 to 2016,CO_(2) concentration in Indonesia showed a trend of increase,which is consistent with the global increase reported by the Greenhouse Gases Observing Satellite(GOSAT)Project.As an archipelago country,the results indicate that SST has a direct effect on the CO_(2) concentration in Indonesia.Their changing exhibits similar fluctuations;meanwhile,CO_(2) concentration and SST also presented positive correlation.In 2015,the number of fire hotspots suddenly increased to 140,699,because of occurrence of the worst forest fire.Due to special geographic conditions,forest fires did not induce CO_(2) concentration changes in Indonesia,but CO_(2) concentration in the corresponding islands showed a trend of increase.CO_(2) concentration increased in Kalimantan during the occurrence of forest fire in September–October 2014,and CO_(2) concentration increased in Kalimantan and Sumatra during the occurrence of forest fire in September–October 2015.Vegetation indices were stable and presented no correlation with CO_(2) concentration.This study demonstrated that OCO-2 is capable of monitoring CO_(2) concentration at a regional scale;additionally,an effective method for using OCO-2 Level 2 products is proposed.展开更多
基金supported by the National Natural Science Foundation of China(NSFC)Grant Nos.11988101,1172531312041303,12041304,12203045,12203070,12103013,T2241020the National SKA Program of China(Nos.2020SKA0120200,2022SKA0130100,2022SKA0130104)+5 种基金the Foundation of Science and Technology of Guizhou Province(No.(2021)023)the Foundation of Guizhou Provincial Education Department(Nos.KY(2021)303,KY(2020)003)support from the National Natural Science Foundation of China under grant U2031117the Youth Innovation Promotion Association CAS(id.2021055)CAS Project for Young Scientists in Basic Research(grant YSBR006)the Cultivation Project for FAST Scientific Payoff and Research Achievement of CAMS-CAS。
文摘We report the discovery of PSR J1909+0122 by the Five-hundred-meter Aperture Spherical Radio Telescope(FAST)as part of the Commensal Radio Astronomy FAST Survey.PSR J1909+0122 has a spin period of 1.257 s and a dispersion measure of 186.2 pc cm^(-3).The averaged pulse profile shows two distinct components.We performed a single-pulse study based on a one-hour observation at 1.25 GHz on 2021 August 23.We used a threshold of 5σ_(ep) to measure the nulling fraction(NF)as 63%±1.5%.The longitude-resolved fluctuation spectra and fast Fourier transform spectra of the binary sequences revealed the quasi-periodicity of nulling with a period of 30 rotation periods.We examined the reliability of the periodicity by comparing it to random noise injection.The NF,E,and modulation periodicity P_(M) of PSR J1909+0122 were compared with other periodic nulling pulsars,showing that the source of J1909+0122 has the second largest NF in the population.Long-term timing observations over six months were used to derive the phase-connected ephemeris of this pulsar.The measured P and P values disfavor dipolar geometry for polar gap models,and the prediction for a space-charge-limited flow model in the case of inverse Compton scattering is only just above the death line.In this work,PSR J1909+0122 has revealed possible correlations between nulling behavior and pulsar properties,which will help to shed light on the pulsar emission mechanism and its temporal evolution in future observations.
文摘Carbon dioxide (CO<sub>2</sub>) is one of the most important greenhouse gases;its concentration and distribution have important implications on climate change. The El Ni?o Southern Oscillation (ENSO) is the Earth’s strongest climate fluctuation on inter-annual time scales and has global impacts. However, to date, there is no research on how ENSO affects the spatial distribution of CO<sub>2</sub> concentration. In this study, we used spatial CO<sub>2</sub> data from the ENVIronmentSATellite (ENVISAT) and the Greenhouse Gases Observing Satellite (GOSAT), the long duration monthly mean atmospheric CO<sub>2</sub> from Mauna Loa Observatory, Multivariate ENSO Index (MEI) from Earth System Research Laboratory to analyze the way that ENSO affects spatial distribution of CO<sub>2</sub> concentration in South America, which is affected by ENSO seriously. Our research revealed that monthly CO<sub>2</sub> growth rate has a moderate, positive correlation relationship with MEI. We used geostatistics to predict and simulate the spatial distribution of CO<sub>2</sub> and found that in south of 12°S, CO<sub>2</sub> concentration of ENSO warm episode is lower than the one of ENSO cold and neutral episodes. ENSO impacts CO<sub>2</sub> spatial distribution mainly in November, December, January and February;moderate-high concentration zone of ENSO warm episode more concentrates in the northern part of South America.
文摘Penile reconstruction following cancer resection has long been a challenge due to demand for both aesthetic and functional preservation. Although various methods have attempted to achieve both goals, none have succeeded entirely. In this report, we introduce a novel reconstructive technique on a 64-year-old patient with squamous cell carcinoma of the glans penis. The technique consisted of two staged procedures. First, a dermal substitute, consisting of bovine collagen, was sutured onto the defect after partial glansectomy and three weeks later, the integrated dermis was covered with autologous non-meshed partial thickness skin graft. Use of this dermal substitute in a staged fashion allowed for ability to await final pathologic margins prior to definitive reconstruction and increased dermal thickness. After 9-month follow-up, sexual function returned within 3 months and the patient remained healed. We found this technique to be useful in concurrently preserving penile function and cosmesis. Future studies should include more patients and longer follow-up.
基金supported by the National Natural Science Foundation of China(Grant Nos.11988101,12103013,12041303,U2031117,12373109,and 12103069)the National SKA Program of China(Grant Nos.2020SKA0120200,2022SKA0130100,and2022SKA0130104)+2 种基金the National Key Research and Development Program of China(Grant No.2023YFB4503300)the Foundation of Science and Technology of Guizhou Province(Grant No.(2021)023)the Foundation of Guizhou Provincial Education Department(Grant Nos.KY(2020)003,and KY(2023)059)。
文摘Globular clusters harbor numerous millisecond pulsars,but long-period pulsars(P 100 ms)are rarely found.In this study,we employed a fast folding algorithm to analyze observational data from multiple globular clusters obtained by the Five-hundredmeter Aperture Spherical radio Telescope(FAST),aiming to detect the existence of long-period pulsars.We estimated the impact of the median filtering algorithm in eliminating red noise on the minimum detectable flux density(S_(min))of pulsars.Subsequently,we successfully discovered two isolated long-period pulsars in M15 with periods approximately equal to 1.928451 and3.960716 s,respectively.On the P-˙P diagram,both pulsars are positioned below the spin-up line,suggesting a possible history of partial recycling in X-ray binary systems disrupted by dynamical encounters later on.According to timing results,these two pulsars exhibit remarkably strong magnetic fields.If the magnetic fields were weakened during the accretion process,then a short duration of accretion might explain the strong magnetic fields of these pulsars.
基金supported by the National Natural Science Foundation of China(No.81930067)Key Project for Clinical Innovation of AMU(China)(No.CX2019LC107).
文摘More than 50%of prostate cancer(PCa)patients have bone metastasis with osteo-blastic lesions.MiR-18a-5p is associated with the development and metastasis of PCa,but it remains unclear whether it is involved in osteoblastic lesions.We first found that miR-18a-5p was highly expressed in the bone microenvironment of patients with PCa bone metastases.To address how miR-18a-5p affects PCa osteoblastic lesions,antagonizing miR-18a-5p in PCa cells or pre-osteoblasts inhibited osteoblast differentiation in vitro.Moreover,injection of PCa cells with miR-18a-5p inhibition improved bone biomechanical properties and bone mineral mass in vivo.Furthermore,miR-18a-5p was transferred to osteoblasts by exosomes derived from PCa cells and targeted the Hist1h2bc gene,resulting in Ctnnb1 up-regulation in the Wnt/β-catenin signaling pathway.Translationally,antagomir-18a-5p significantly improved bone biomechanical properties and alleviated sclerotic lesions from osteoblastic me-tastases in BALB/c nude mice.These data suggest that inhibition of exosome-delivered miR-18a-5p ameliorates PCa-induced osteoblastic lesions.
文摘We used OCO-2 products and considered three factors that potentially affect CO_(2) concentration in Indonesia:sea surface temperature(SST),forest fires and vegetation.From 2014 to 2016,CO_(2) concentration in Indonesia showed a trend of increase,which is consistent with the global increase reported by the Greenhouse Gases Observing Satellite(GOSAT)Project.As an archipelago country,the results indicate that SST has a direct effect on the CO_(2) concentration in Indonesia.Their changing exhibits similar fluctuations;meanwhile,CO_(2) concentration and SST also presented positive correlation.In 2015,the number of fire hotspots suddenly increased to 140,699,because of occurrence of the worst forest fire.Due to special geographic conditions,forest fires did not induce CO_(2) concentration changes in Indonesia,but CO_(2) concentration in the corresponding islands showed a trend of increase.CO_(2) concentration increased in Kalimantan during the occurrence of forest fire in September–October 2014,and CO_(2) concentration increased in Kalimantan and Sumatra during the occurrence of forest fire in September–October 2015.Vegetation indices were stable and presented no correlation with CO_(2) concentration.This study demonstrated that OCO-2 is capable of monitoring CO_(2) concentration at a regional scale;additionally,an effective method for using OCO-2 Level 2 products is proposed.