BACKGROUND: Translocation or transplantation of nerve stem has good effect; however, nervous function of donator is completely lost. If some nerve stem is damaged, sensory tracts are intercepted from the near nerve s...BACKGROUND: Translocation or transplantation of nerve stem has good effect; however, nervous function of donator is completely lost. If some nerve stem is damaged, sensory tracts are intercepted from the near nerve stem by nutrient vessels to regard as neural graft for transferring and bridging which may repair injured nerve and decrease neural functional loss of donator. OBJECTIVE: To observe anatomical peculiarities on sensory tracts of wrist median nerve pedicled with nutrient vessels transferring to bridge wrist ulnar nerve defect, and to investigate its feasibility. DESIGN:Duplicated and measured design.SETTING : Anatomy Department of Medical College affiliated to Nanhua University.MATERIALS: A total of 14 samples of upper limbs were selected from adult unnamed corpse and volunteers.METHODS: The experiment was completed at the Clinical Application Anatomy Laboratory of Medical College affiliated to Nanhua University from September to November 2005. Samples were perfused with red emulsion through artery to observe length, fibrous bands and blood supply of median nerve and ulnar nerve at wrist. Boundary of median nerve at wrist ranged from superficial site between flexor carpi radialis and palmaris Iongus to branch of common palmar digital nerves. Ulnar nerve at wrist ranged from branch of back of the hand to site of common palmar digital nerves. Proximal boundary of the two nerves was crossed from 1/8 to 2/8 region of forearm. Samples of upper limbs from 1 case were selected to simulate operation on sensory tracts of wrist median nerve pedicled with nutrient vessels transferring to bridge wrist ulnar nerve. MAIN OUTCOME MEASURES: Anatomical peculiarities on sensory tracts of wrist median nerve pedicled with nutrient vessels transferring to bridge wrist ulnar nerve defect. RESULTS: ① The length of wrist median nerves was 7.8 (7.5-8.1) cm. There were 19 to 27 nerve tracts in it and the majority belonged to sensory tracts on the ulnar side, in which non-damaged separated length was about 10.0 cm to 14.0 cm. The third, second and first tracts of cutaneous branches at digital interspace and radialis of thumb arrayed from ulnaris to radialis by turns, and numbers of bands were 6.9, 7.4 and 7.2, respectively. The bands in total were 21.6. Cutaneous branches of palm entered from lateral margin of radialis and were completely separated at wrist. Two-thirds of ulnaris at nerve stem, i.e. the third, second and first tracts of cutaneous branches at digital interspace, were separated, which had little effect on sensation in distribution of median nerve. ② Its nutrient vessels originated from radial arteries about 6.2 (6.1-6.6) cm above radial styloid process were 1.2 (1.1-1.4) mm in outer diameter. The length was 5.7 (5.1-6.1) cm.③ The length of wrist ulnar nerve were 9.4 (8.9-9.7) cm and the number of nervous tract were 14 to 19, in which sensory tracts on the anterior external side were approximately equal to motor and mixed tracts on the posterior internal side in quantity. Sensory tracts were located at radialis of palm and motor tracts were located at ulnaris of back. CONCLUSION :① Character and position of median nerve fibre bundle are clear, and length of non-damage separation of sensory tracts is coincidence with the request of transferring to bridge. ② Summation of the third, second and first tracts of cutaneous branches at digital interspace may be satisfactory to bridge of ulnar nerve at wrist (14-19 bands). ③ This technique has little effect on sensation in distribution of median nerve. Nutrient artery of median nerve locates constantly; journey table is superficial and is easily to find out; caliber of arterial canal is thick; blood supply is plentiful; length of pedicel is suitable for translocation. The sensery tracts of wrist median nerve pedicled with nutrient vessels can be applied as nervous grafts to join injured gap in wrist ulnar nerve.展开更多
During the long term evolution of globular clusters(GCs), some member stars are lost to the field. The recently found nitrogen-rich(N-rich) metal-poor field stars are promising candidates of these GC escapees, since N...During the long term evolution of globular clusters(GCs), some member stars are lost to the field. The recently found nitrogen-rich(N-rich) metal-poor field stars are promising candidates of these GC escapees, since N enhancement is the fingerprint of chemically enhanced populations in GCs. In this work, we discuss the possibility of identifying N-rich metal-poor field stars with the upcoming Chinese Space Station Telescope(CSST). We focus on the main survey camera with NUV, u, g, r, i, z, y filters and slitless spectrograph with a resolution about 200.The combination of UV sensitive equipment and prominent N-related molecular lines in the UV band bodes well for the identification: the color–color diagram of(u-g) versus(g-r) is capable of separating N-rich field stars from normal halo stars, if metallicity can be estimated without using the information on u-band photometry.Besides, the synthetic spectra show that a signal-to-noise ratio of 10 is sufficient to identify N-rich field stars. In the near future, a large sample of N-rich field stars found by CSST, combined with state-of-the-art N-body simulations will be crucial to deciphering GC-Galaxy co-evolution.展开更多
To the Editor: With interest we read the article by Yu et al[1] about a retrospective study of 13 pediatric patients with Leigh syndrome from a single center in China collected over a period of 17 years. The authors c...To the Editor: With interest we read the article by Yu et al[1] about a retrospective study of 13 pediatric patients with Leigh syndrome from a single center in China collected over a period of 17 years. The authors concluded that patients with ophthalmoplegia, muscle weakness, ataxia, and respiratory insufficiency should be screened for mutations in genes located on the mtDNA.[1] Patients with suspected Leigh syndrome are recommended to undergo determination of cerebrospinal fluid (CSF) lactate and cerebral imaging.[1] We have the following comment and concerns.展开更多
Some problems of groundwater development in the Niger Delta ranging from negligence to geological peculiarities are examined to highlight the importance and application of geologic knowledge and research for decision ...Some problems of groundwater development in the Niger Delta ranging from negligence to geological peculiarities are examined to highlight the importance and application of geologic knowledge and research for decision making and averting failure in groundwater development for provisional use. Although the geology and hydrogeologic properties of the aquifer system in the Niger Delta immensely favors groundwater development, there are several recorded cases of failed groundwater development projects poor water quality, dry boreholes and boreholes with surprisingly low yield which could have been avoided. This is due to the perception that since groundwater is prolific, geologic and locational peculiarities can be ignored. This research has highlighted the importance of the knowledge of the hydrogeology of the different geologic units as significant factor in the success of groundwater projects through the correlation of past research of geologic units and groundwater potentials, quality and challenges with the present projects implemented in some of the locations. Cases where groundwater projects are executed with wrong exploration options and without consideration of the peculiarity of the geologic units of the project area, including engagement of incompetent contractors, and negligence to the existing regulatory framework for groundwater development in Nigeria are presented. In order to promote sustainable groundwater development and management in the Niger Delta, this research highlights and recommends the pragmatic use of geologic information including various technical, institutional, regulatory and management measures which have the capacity to avert challenges in groundwater development for provisional use.展开更多
We measure the significance of thermally pulsing asymptotic giant branch(TP-AGB)stars via the spectral energy distributions(SEDs)of a sample of post-starburst(PSB)galaxies at z=0.2-0.7.Using ground-and space-based pho...We measure the significance of thermally pulsing asymptotic giant branch(TP-AGB)stars via the spectral energy distributions(SEDs)of a sample of post-starburst(PSB)galaxies at z=0.2-0.7.Using ground-and space-based photometry from the 3D-HST catalog,as well as associated near-infrared(NIR)Hubble Space Telescope(HST)slitless grism spectroscopy,we evaluate the importance of TP-AGB stars in the SEDs of 177 PSB galaxies by fitting simple stellar populations with different levels of TP-AGB contributions.The grism spectra,despite their low resolution of R~100,enable the detection of molecular features specific to TP-AGB stars and thus improve constraints on their contribution.A majority(~70%)of galaxies in the PSB sample show features indicative of TPAGB stars,while the remainder does not and they are well fit by Bruzual&Charlot TP-AGB light models.Stacked spectra of sources classified to be the best fit by TP-AGB heavy/mild models reveal strong detections of NIR molecular features associated with TP-AGB stars.Additionally,we observe a tentative trend with redshift where more TP-AGB heavy galaxies are observed in the higher redshift PSB galaxy population.Finally,neglecting the contribution of TP-AGB stars can yield an over-prediction of stellar masses measured in the K-band ranging from 0.13-0.23 dex.展开更多
In selecting methods of liquidation of natural pollution resulted from oil products (OP) in the cold regions, such as in the north coast of the Sea of Okhotsk, it is necessary to take into consideration the peculiarit...In selecting methods of liquidation of natural pollution resulted from oil products (OP) in the cold regions, such as in the north coast of the Sea of Okhotsk, it is necessary to take into consideration the peculiarities of the OP and the object polluted in cold and warm periods. Generally, in cold time snow cover with thickness of 1.0m or more presents, so the OP is partly absorbed by the silt in the snow, then the viscosity of snow is strengthened due to the aggregate of the hard hydrocarbon components (HСС) with negative temperature in the OP. The HCC is the most active when the molecular of carbon atom is less than 10, and could not be harden at the temperature below (-30 ℃). However, in summer time the spilled HCC is partly evaporated, but the tar and asphalt enrich the OP there. In the mountainous regions at the deep deposition of underground water, in summer the OP might be brought by the gas stream in the massifs of the fracture rocks upper on the slope. According to the peculiarities, the methods of fighting the nature, polluted by the OP in the regions of the Sub-Arctic; are explained, and they are representative in the north coast of the Sea of Okhotsk.展开更多
Ⅰ.Each of the statements below is followed by four alternative answers.Choose the one that wouldbest complete the statement.1.Polysemy is a common feature peculiar to ___.A.English only B.Chinese only C.all natural l...Ⅰ.Each of the statements below is followed by four alternative answers.Choose the one that wouldbest complete the statement.1.Polysemy is a common feature peculiar to ___.A.English only B.Chinese only C.all natural languages D.some natural languages2.From the ____ point of view,polysemy is assumed to be the result of growth and development of thesemantic structure of one and same word.A.linguistic B.diachronic C.synchronic D.展开更多
Happy Days,one of Samuel Beckett's renowned works,is remarkable for its absurdity.The paper approaches the predominant feature from such aspects as fragmented characters,disconnected language,peculiar structure an...Happy Days,one of Samuel Beckett's renowned works,is remarkable for its absurdity.The paper approaches the predominant feature from such aspects as fragmented characters,disconnected language,peculiar structure and grotesque stagecraft.展开更多
Two Li-rich candidates,TYC 1338-1410-1 and TYC 2825-596-1,were observed by the new high-resolution echelle spectrograph,LAMOST/HRS.Based on their high-resolution and high-signal-tonoise ratio(SNR)spectra,we derived st...Two Li-rich candidates,TYC 1338-1410-1 and TYC 2825-596-1,were observed by the new high-resolution echelle spectrograph,LAMOST/HRS.Based on their high-resolution and high-signal-tonoise ratio(SNR)spectra,we derived stellar parameters and abundances of 14 important elements for the two candidates.The stellar parameters and lithium abundances indicate that they are Li-rich K-type giants,and having A(Li)NLTE and 2.91 dex,respectively.Our analysis suggests that TYC 1338-1410-1 is probably a red giant branch(RGB)star at the bump stage,while TYC 2825-596-1 is most likely to be a core helium-burning red clump(RC)star.The line profiles of both spectra indicate that the two Li-rich giants are slow rotators and do not show infrared(IR)excess.We conclude that engulfment is not the lithium enrichment mechanism for either star.The enriched lithium of TYC 1338-1410-1 could be created via the Cameron-Fowler mechanism,while the lithium excess in TYC 2825-596-1 could be associated with either non-canonical mixing processes or He-flash.展开更多
1.存在“there”与地点“there”的区分在讨论“there”插入转换规则(There-Insertion)之前,有必要对英语中“there”这个词形的两种不同用法作一区别。例(1)a.There was a student on the plat-form.b.There will be some visitors her...1.存在“there”与地点“there”的区分在讨论“there”插入转换规则(There-Insertion)之前,有必要对英语中“there”这个词形的两种不同用法作一区别。例(1)a.There was a student on the plat-form.b.There will be some visitors heretomorrow.c.There reigns a peculiar silence inhere;展开更多
The six antigens of Cysticercus cellulosae: CFag, CSag, CBWag, CWag, UCWag and TSag were prepared respectively. The amino acids of the antigens were determined quantitative by automatic amino acid analyzer. The relati...The six antigens of Cysticercus cellulosae: CFag, CSag, CBWag, CWag, UCWag and TSag were prepared respectively. The amino acids of the antigens were determined quantitative by automatic amino acid analyzer. The relationship of original reaction was confirmed between amino acids and antigens. The results showed that there were 17 amino acids among all of the antigens. There were no significant difference (P >0.05) of Asp, Clu, Lys, His in composition of all antigens by data analysis software SPSS. There are also no significant difference (P >0.05) in the composition of all amino acids between CSag and CBWag. The composition of Thr, Ser, Tyr, Ved, Pro in UCWag shows significant difference (P<0.05) with other antigens. The sensitivity and peculiarity of UCWag are higher than that of the others. Pro and Glu show significant linear correspondence with sensitivity and peculiarity of antigens respectively.展开更多
Strongly Mg-enhanced stars with [Mg/Fe] 〉 1.0 show peculiar abundance patterns and hence are of great interest for our understanding of stellar formation and chemical evolution of the Galaxy. A systematic search for ...Strongly Mg-enhanced stars with [Mg/Fe] 〉 1.0 show peculiar abundance patterns and hence are of great interest for our understanding of stellar formation and chemical evolution of the Galaxy. A systematic search for strongly Mg-enhanced stars based on low-resolution (R≈2000) spectra from the Sloan Digital Sky Survey (SDSS) is carried out by finding the synthetic spectrum that best matches the observed one in the region of Mg I b lines around λ5170 ,A via a profile matching method. The advantage of our method is that fitting parameters are refined by reproducing the [Mg/Fe] ratios of 47 stars from the very precise high-resolution spectroscopic (HRS) analysis by Nissen & Schuster; and these parameters are crucial to the precision and validity of the derived Mg abundances. As a further check of our method, Mg abun- dances are estimated with our method for member stars in four Galactic globular clus- ters (M92, M 13, M3, M71) which cover the same metallicity range as our sample, and the results are in good agreement with those of HRS analysis in the literature. The val- idation of our method is also demonstrated by the agreement of [Mg/Fe] between our values and those of HRS analysis by Aoki et al. Finally, 33 candidates of strongly Mg- enhanced stars with [Mg/Fe]〉 1.0 are selected from 14 850 F and G stars. Follow-up observations will be carried out on these candidates with high-resolution spectroscopy by large telescopes in the near future, so as to check our selection procedure and to perform a precise and detailed abundance analysis and to explore the origins of these stars.展开更多
The effects of soil aeration on physiological characters and root tuber yield of Ipomoea batatas (L.) Lam. CV Lushu7 and Xushu18 were studied. The results showed that soil aeration improvement could increase ATP conte...The effects of soil aeration on physiological characters and root tuber yield of Ipomoea batatas (L.) Lam. CV Lushu7 and Xushu18 were studied. The results showed that soil aeration improvement could increase ATP content and ATPase activity in functional leaves and root tubers and ABA content in root tubers. It also accelerated the transportation of 14C-photosynthate from leaves to root tubers and enhanced dry matter distribution in root tubers and thus root tuber yield was significantly raised. The role of ATP, ATPase and ABA in accelerating the transportation of 14C-photosynthate was discussed based on the changes of soluble carbonhydrate content in sweet potato plant.展开更多
Object J053253.51–695915.1(J053253)in the Large Magellanic Cloud(LMC)is reported as a young stellar object(YSO).Its chemical abundances reflect the initial composition of the gas cloud in which the star formed.Howeve...Object J053253.51–695915.1(J053253)in the Large Magellanic Cloud(LMC)is reported as a young stellar object(YSO).Its chemical abundances reflect the initial composition of the gas cloud in which the star formed.However,the discovery that this star shows the enhancement of the neutron(n)-capture elements and the higher ratio of the heavier n-capture elements relative to the lighter n-capture elements is puzzling.Using an abundance decomposed method,we explore the astrophysical origins of the n-capture elements in this star.We find that the abundance characteristic of the higher ratio of the heavier n-capture elements to the lighter n-capture elements can be explained by the pollution of the r-process event and the contamination of the s-process material.展开更多
Most close double helium white dwarfs will merge within a Hubble time due to orbital decay by gravitational wave radiation.However,a significant fraction with low mass ratios will survive for a long time as a conseque...Most close double helium white dwarfs will merge within a Hubble time due to orbital decay by gravitational wave radiation.However,a significant fraction with low mass ratios will survive for a long time as a consequence of stable mass transfer.Such stable mass transfer between two helium white dwarfs(He WDs) provides one channel for the production of AM CVn binary stars.In previous calculations of double He WD progenitors,the accreting He WD was treated as a point mass.We have computed the evolution of 16 double He WD models in order to investigate the consequences of treating the evolution of both components in detail.We find that the boundary between binaries having stable and unstable mass transfer is slightly modified by this approach.By comparing with observed periods and mass ratios,we redetermine masses of eight known AM CVn stars by our double He WDs channel,i.e.HM Cnc,AM CVn,V406 Hya,J0926,J1240,GP Com,Gaia14 aae and V396 Hya.We propose that central spikes in the triple-peaked emission spectra of J1240,GP Com and V396 Hya and the surface abundance ratios of N/C/O in GP Com can be explained by the stable double He WD channel.The mass estimates derived from our calculations are used to discuss the predicted gravitational wave signal in the context of the Laser Interferometer Space Antenna(LISA) project.展开更多
The magnetoresistive properties of discontinuous ferromagnetic Fe and Co thin films deposited by electron-beam sputtering onto glass substrates at room temperature were investigated. Tunnel magnetoresistance(MR) was o...The magnetoresistive properties of discontinuous ferromagnetic Fe and Co thin films deposited by electron-beam sputtering onto glass substrates at room temperature were investigated. Tunnel magnetoresistance(MR) was observed for all of the as-deposited samples. The maximum MR was observed for Fe thin films with an effective thickness of 17 nm. In the case of the Co thin films, the annealing process led to a change of the type of MR to anisotropic at Co film thicknesses(dCo) of 15 ≤ d_(Co) ≤ 25 nm and to positive isotropic at thicknesses of d_(Co) < 15 nm. By contrast, the MR type of Fe thin films did not change.展开更多
Radiative lifetimes of two short-lived levels (i.e. 4f^8 (TF6)6p^1/2 (6, 1/2)11/2,13/2) in Tb Ⅲ are measured by time-resolved laser-induced fluorescence (LIE) technique with a two-step excitation process. Fre...Radiative lifetimes of two short-lived levels (i.e. 4f^8 (TF6)6p^1/2 (6, 1/2)11/2,13/2) in Tb Ⅲ are measured by time-resolved laser-induced fluorescence (LIE) technique with a two-step excitation process. Free Tb Ⅲ ions are produced in a laser-induced plasma. Lifetime values are evaluated with a deconvolution procedure of the timeresolved fluorescence signal with the temporal shape of second-step excitation pulse (about 1 ns). The lifetimes of the 4f^8 (^7F6)6p^1/2 (6, 1/2)11/2 and 4f^8(^7F6)6p^1/2 (6, 1/2)13/2 levels are determined to be 1.9 (2) and 2.0 (2)ns, respectively.展开更多
文摘BACKGROUND: Translocation or transplantation of nerve stem has good effect; however, nervous function of donator is completely lost. If some nerve stem is damaged, sensory tracts are intercepted from the near nerve stem by nutrient vessels to regard as neural graft for transferring and bridging which may repair injured nerve and decrease neural functional loss of donator. OBJECTIVE: To observe anatomical peculiarities on sensory tracts of wrist median nerve pedicled with nutrient vessels transferring to bridge wrist ulnar nerve defect, and to investigate its feasibility. DESIGN:Duplicated and measured design.SETTING : Anatomy Department of Medical College affiliated to Nanhua University.MATERIALS: A total of 14 samples of upper limbs were selected from adult unnamed corpse and volunteers.METHODS: The experiment was completed at the Clinical Application Anatomy Laboratory of Medical College affiliated to Nanhua University from September to November 2005. Samples were perfused with red emulsion through artery to observe length, fibrous bands and blood supply of median nerve and ulnar nerve at wrist. Boundary of median nerve at wrist ranged from superficial site between flexor carpi radialis and palmaris Iongus to branch of common palmar digital nerves. Ulnar nerve at wrist ranged from branch of back of the hand to site of common palmar digital nerves. Proximal boundary of the two nerves was crossed from 1/8 to 2/8 region of forearm. Samples of upper limbs from 1 case were selected to simulate operation on sensory tracts of wrist median nerve pedicled with nutrient vessels transferring to bridge wrist ulnar nerve. MAIN OUTCOME MEASURES: Anatomical peculiarities on sensory tracts of wrist median nerve pedicled with nutrient vessels transferring to bridge wrist ulnar nerve defect. RESULTS: ① The length of wrist median nerves was 7.8 (7.5-8.1) cm. There were 19 to 27 nerve tracts in it and the majority belonged to sensory tracts on the ulnar side, in which non-damaged separated length was about 10.0 cm to 14.0 cm. The third, second and first tracts of cutaneous branches at digital interspace and radialis of thumb arrayed from ulnaris to radialis by turns, and numbers of bands were 6.9, 7.4 and 7.2, respectively. The bands in total were 21.6. Cutaneous branches of palm entered from lateral margin of radialis and were completely separated at wrist. Two-thirds of ulnaris at nerve stem, i.e. the third, second and first tracts of cutaneous branches at digital interspace, were separated, which had little effect on sensation in distribution of median nerve. ② Its nutrient vessels originated from radial arteries about 6.2 (6.1-6.6) cm above radial styloid process were 1.2 (1.1-1.4) mm in outer diameter. The length was 5.7 (5.1-6.1) cm.③ The length of wrist ulnar nerve were 9.4 (8.9-9.7) cm and the number of nervous tract were 14 to 19, in which sensory tracts on the anterior external side were approximately equal to motor and mixed tracts on the posterior internal side in quantity. Sensory tracts were located at radialis of palm and motor tracts were located at ulnaris of back. CONCLUSION :① Character and position of median nerve fibre bundle are clear, and length of non-damage separation of sensory tracts is coincidence with the request of transferring to bridge. ② Summation of the third, second and first tracts of cutaneous branches at digital interspace may be satisfactory to bridge of ulnar nerve at wrist (14-19 bands). ③ This technique has little effect on sensation in distribution of median nerve. Nutrient artery of median nerve locates constantly; journey table is superficial and is easily to find out; caliber of arterial canal is thick; blood supply is plentiful; length of pedicel is suitable for translocation. The sensery tracts of wrist median nerve pedicled with nutrient vessels can be applied as nervous grafts to join injured gap in wrist ulnar nerve.
基金support from the China Manned Space Project Nos. CMS-CSST-2021-B03,CMS-CSST-2021-A08, and________the National Natural Science Foundation of China under grant No. 12233013,12073090+8 种基金the Natural Science Foundation of Guangdong Province under grant No. 2022A1515010732grant support provided by Proyecto Fondecyt Iniciación No. 11220340ANID Concurso de Fomento a la Vinculación Internacional para Instituciones de Investigación Regionales (Modalidad corta duración) Proyecto No. FOVI210020Joint Committee ESO-Government of Chile 2021 (ORP 023/2021)Becas Santander Movilidad Internacional Profesores 2022, Banco Santander Chilesupport from the National Natural Science Foundation of China through grant 21BAA00619the one-hundred-talent project of Sun Yat-sen Universitythe Fundamental Research Funds for the Central UniversitiesSun Yat-sen University (22hytd09)。
文摘During the long term evolution of globular clusters(GCs), some member stars are lost to the field. The recently found nitrogen-rich(N-rich) metal-poor field stars are promising candidates of these GC escapees, since N enhancement is the fingerprint of chemically enhanced populations in GCs. In this work, we discuss the possibility of identifying N-rich metal-poor field stars with the upcoming Chinese Space Station Telescope(CSST). We focus on the main survey camera with NUV, u, g, r, i, z, y filters and slitless spectrograph with a resolution about 200.The combination of UV sensitive equipment and prominent N-related molecular lines in the UV band bodes well for the identification: the color–color diagram of(u-g) versus(g-r) is capable of separating N-rich field stars from normal halo stars, if metallicity can be estimated without using the information on u-band photometry.Besides, the synthetic spectra show that a signal-to-noise ratio of 10 is sufficient to identify N-rich field stars. In the near future, a large sample of N-rich field stars found by CSST, combined with state-of-the-art N-body simulations will be crucial to deciphering GC-Galaxy co-evolution.
文摘To the Editor: With interest we read the article by Yu et al[1] about a retrospective study of 13 pediatric patients with Leigh syndrome from a single center in China collected over a period of 17 years. The authors concluded that patients with ophthalmoplegia, muscle weakness, ataxia, and respiratory insufficiency should be screened for mutations in genes located on the mtDNA.[1] Patients with suspected Leigh syndrome are recommended to undergo determination of cerebrospinal fluid (CSF) lactate and cerebral imaging.[1] We have the following comment and concerns.
文摘Some problems of groundwater development in the Niger Delta ranging from negligence to geological peculiarities are examined to highlight the importance and application of geologic knowledge and research for decision making and averting failure in groundwater development for provisional use. Although the geology and hydrogeologic properties of the aquifer system in the Niger Delta immensely favors groundwater development, there are several recorded cases of failed groundwater development projects poor water quality, dry boreholes and boreholes with surprisingly low yield which could have been avoided. This is due to the perception that since groundwater is prolific, geologic and locational peculiarities can be ignored. This research has highlighted the importance of the knowledge of the hydrogeology of the different geologic units as significant factor in the success of groundwater projects through the correlation of past research of geologic units and groundwater potentials, quality and challenges with the present projects implemented in some of the locations. Cases where groundwater projects are executed with wrong exploration options and without consideration of the peculiarity of the geologic units of the project area, including engagement of incompetent contractors, and negligence to the existing regulatory framework for groundwater development in Nigeria are presented. In order to promote sustainable groundwater development and management in the Niger Delta, this research highlights and recommends the pragmatic use of geologic information including various technical, institutional, regulatory and management measures which have the capacity to avert challenges in groundwater development for provisional use.
基金based on observation taken by the 3D-HST Treasury Program(GO 12177 and 12328)with NASA/ESA HSToperated by the Association of Universities for Research in Astronomy Inc.,under NASA contract NAS5-26555+1 种基金supported by the National Natural Science Foundation of China(NSFC,Grant No.U1931209)the National Key R&D Program of China(No.2019YFA0405502)。
文摘We measure the significance of thermally pulsing asymptotic giant branch(TP-AGB)stars via the spectral energy distributions(SEDs)of a sample of post-starburst(PSB)galaxies at z=0.2-0.7.Using ground-and space-based photometry from the 3D-HST catalog,as well as associated near-infrared(NIR)Hubble Space Telescope(HST)slitless grism spectroscopy,we evaluate the importance of TP-AGB stars in the SEDs of 177 PSB galaxies by fitting simple stellar populations with different levels of TP-AGB contributions.The grism spectra,despite their low resolution of R~100,enable the detection of molecular features specific to TP-AGB stars and thus improve constraints on their contribution.A majority(~70%)of galaxies in the PSB sample show features indicative of TPAGB stars,while the remainder does not and they are well fit by Bruzual&Charlot TP-AGB light models.Stacked spectra of sources classified to be the best fit by TP-AGB heavy/mild models reveal strong detections of NIR molecular features associated with TP-AGB stars.Additionally,we observe a tentative trend with redshift where more TP-AGB heavy galaxies are observed in the higher redshift PSB galaxy population.Finally,neglecting the contribution of TP-AGB stars can yield an over-prediction of stellar masses measured in the K-band ranging from 0.13-0.23 dex.
文摘In selecting methods of liquidation of natural pollution resulted from oil products (OP) in the cold regions, such as in the north coast of the Sea of Okhotsk, it is necessary to take into consideration the peculiarities of the OP and the object polluted in cold and warm periods. Generally, in cold time snow cover with thickness of 1.0m or more presents, so the OP is partly absorbed by the silt in the snow, then the viscosity of snow is strengthened due to the aggregate of the hard hydrocarbon components (HСС) with negative temperature in the OP. The HCC is the most active when the molecular of carbon atom is less than 10, and could not be harden at the temperature below (-30 ℃). However, in summer time the spilled HCC is partly evaporated, but the tar and asphalt enrich the OP there. In the mountainous regions at the deep deposition of underground water, in summer the OP might be brought by the gas stream in the massifs of the fracture rocks upper on the slope. According to the peculiarities, the methods of fighting the nature, polluted by the OP in the regions of the Sub-Arctic; are explained, and they are representative in the north coast of the Sea of Okhotsk.
文摘Ⅰ.Each of the statements below is followed by four alternative answers.Choose the one that wouldbest complete the statement.1.Polysemy is a common feature peculiar to ___.A.English only B.Chinese only C.all natural languages D.some natural languages2.From the ____ point of view,polysemy is assumed to be the result of growth and development of thesemantic structure of one and same word.A.linguistic B.diachronic C.synchronic D.
文摘Happy Days,one of Samuel Beckett's renowned works,is remarkable for its absurdity.The paper approaches the predominant feature from such aspects as fragmented characters,disconnected language,peculiar structure and grotesque stagecraft.
基金the National Key R&D Program of China(No.2019YFA0405502)the Key Research Program of the Chinese Academy of Sciences under grant No.XDPB09-02+8 种基金the National Natural Science Foundation of China(Grant Nos.11973052,11833006,11473033 and 11603037)the International partnership program’s Key foreign cooperation project,Bureau of International Cooperation,Chinese Academy of Sciences(No.114A32KYSB20160049)supported by the Astronomical Big Data Joint Research Center,co-founded by the National Astronomical Observatories,Chinese Academy of Sciences and Alibaba Cloudpartially supported by the Open Project Program of the Key Laboratory of Optical Astronomy,National Astronomical Observatories,Chinese Academy of Sciencesthe financial support from China Scholarship Council(CSC,No.201604910642)for his study at New Mexico State University in the United States of Americathe supports from Youth Innovation Promotion Association,Chinese Academy of SciencesGuo Shou Jing Telescope(the Large Sky Area Multi-Object Fiber Spectroscopic Telescope LAMOST)is a National Major Scientific Project built by the Chinese Academy of Sciences.Funding for the project has been provided by the National Development and Reform Commissionthe NASA/IPAC Infrared Science Archive,which is funded by the National Aeronautics and Space Administrationthe Wide-field Infrared Survey Explorer,which is a joint project of the University of California,Los Angeles,and the Jet Propulsion Laboratory/California Institute of Technology,funded by the National Aeronautics and Space Administration。
文摘Two Li-rich candidates,TYC 1338-1410-1 and TYC 2825-596-1,were observed by the new high-resolution echelle spectrograph,LAMOST/HRS.Based on their high-resolution and high-signal-tonoise ratio(SNR)spectra,we derived stellar parameters and abundances of 14 important elements for the two candidates.The stellar parameters and lithium abundances indicate that they are Li-rich K-type giants,and having A(Li)NLTE and 2.91 dex,respectively.Our analysis suggests that TYC 1338-1410-1 is probably a red giant branch(RGB)star at the bump stage,while TYC 2825-596-1 is most likely to be a core helium-burning red clump(RC)star.The line profiles of both spectra indicate that the two Li-rich giants are slow rotators and do not show infrared(IR)excess.We conclude that engulfment is not the lithium enrichment mechanism for either star.The enriched lithium of TYC 1338-1410-1 could be created via the Cameron-Fowler mechanism,while the lithium excess in TYC 2825-596-1 could be associated with either non-canonical mixing processes or He-flash.
文摘1.存在“there”与地点“there”的区分在讨论“there”插入转换规则(There-Insertion)之前,有必要对英语中“there”这个词形的两种不同用法作一区别。例(1)a.There was a student on the plat-form.b.There will be some visitors heretomorrow.c.There reigns a peculiar silence inhere;
文摘The six antigens of Cysticercus cellulosae: CFag, CSag, CBWag, CWag, UCWag and TSag were prepared respectively. The amino acids of the antigens were determined quantitative by automatic amino acid analyzer. The relationship of original reaction was confirmed between amino acids and antigens. The results showed that there were 17 amino acids among all of the antigens. There were no significant difference (P >0.05) of Asp, Clu, Lys, His in composition of all antigens by data analysis software SPSS. There are also no significant difference (P >0.05) in the composition of all amino acids between CSag and CBWag. The composition of Thr, Ser, Tyr, Ved, Pro in UCWag shows significant difference (P<0.05) with other antigens. The sensitivity and peculiarity of UCWag are higher than that of the others. Pro and Glu show significant linear correspondence with sensitivity and peculiarity of antigens respectively.
基金Supported by the National Natural Science Foundation of China
文摘Strongly Mg-enhanced stars with [Mg/Fe] 〉 1.0 show peculiar abundance patterns and hence are of great interest for our understanding of stellar formation and chemical evolution of the Galaxy. A systematic search for strongly Mg-enhanced stars based on low-resolution (R≈2000) spectra from the Sloan Digital Sky Survey (SDSS) is carried out by finding the synthetic spectrum that best matches the observed one in the region of Mg I b lines around λ5170 ,A via a profile matching method. The advantage of our method is that fitting parameters are refined by reproducing the [Mg/Fe] ratios of 47 stars from the very precise high-resolution spectroscopic (HRS) analysis by Nissen & Schuster; and these parameters are crucial to the precision and validity of the derived Mg abundances. As a further check of our method, Mg abun- dances are estimated with our method for member stars in four Galactic globular clus- ters (M92, M 13, M3, M71) which cover the same metallicity range as our sample, and the results are in good agreement with those of HRS analysis in the literature. The val- idation of our method is also demonstrated by the agreement of [Mg/Fe] between our values and those of HRS analysis by Aoki et al. Finally, 33 candidates of strongly Mg- enhanced stars with [Mg/Fe]〉 1.0 are selected from 14 850 F and G stars. Follow-up observations will be carried out on these candidates with high-resolution spectroscopy by large telescopes in the near future, so as to check our selection procedure and to perform a precise and detailed abundance analysis and to explore the origins of these stars.
文摘The effects of soil aeration on physiological characters and root tuber yield of Ipomoea batatas (L.) Lam. CV Lushu7 and Xushu18 were studied. The results showed that soil aeration improvement could increase ATP content and ATPase activity in functional leaves and root tubers and ABA content in root tubers. It also accelerated the transportation of 14C-photosynthate from leaves to root tubers and enhanced dry matter distribution in root tubers and thus root tuber yield was significantly raised. The role of ATP, ATPase and ABA in accelerating the transportation of 14C-photosynthate was discussed based on the changes of soluble carbonhydrate content in sweet potato plant.
基金supported by the National Natural Science Foundation of China(Grant Nos.11673007,11547041,11643007 and 11773009)the Natural Science Foundation of Hebei Province(Grant No.A2019208194)。
文摘Object J053253.51–695915.1(J053253)in the Large Magellanic Cloud(LMC)is reported as a young stellar object(YSO).Its chemical abundances reflect the initial composition of the gas cloud in which the star formed.However,the discovery that this star shows the enhancement of the neutron(n)-capture elements and the higher ratio of the heavier n-capture elements relative to the lighter n-capture elements is puzzling.Using an abundance decomposed method,we explore the astrophysical origins of the n-capture elements in this star.We find that the abundance characteristic of the higher ratio of the heavier n-capture elements to the lighter n-capture elements can be explained by the pollution of the r-process event and the contamination of the s-process material.
基金supported by the CAS ‘Light of West China’ program(2015-XBQNA-02)the National Natural Science Foundation of China(NSFC,Grant Nos.10933002,11703001 and 11273007)+5 种基金the Joint Research Fund in Astronomy(U1631236) under cooperative agreement between the NSFC and the Chinese Academy of Sciences(CAS)the Strategic Priority Research Program of the Chinese Academy of Sciences(No.XDB2304100)the China Postdoctoral Science Foundationthe Fundamental Research Funds for the Central UniversitiesThe Armagh Observatory and Planetarium are supported by a grant from the Northern Ireland Department for Communitiessupport from the UK Science and Technology Facilities Council(STFC)(Grant No.ST/M000834/1)
文摘Most close double helium white dwarfs will merge within a Hubble time due to orbital decay by gravitational wave radiation.However,a significant fraction with low mass ratios will survive for a long time as a consequence of stable mass transfer.Such stable mass transfer between two helium white dwarfs(He WDs) provides one channel for the production of AM CVn binary stars.In previous calculations of double He WD progenitors,the accreting He WD was treated as a point mass.We have computed the evolution of 16 double He WD models in order to investigate the consequences of treating the evolution of both components in detail.We find that the boundary between binaries having stable and unstable mass transfer is slightly modified by this approach.By comparing with observed periods and mass ratios,we redetermine masses of eight known AM CVn stars by our double He WDs channel,i.e.HM Cnc,AM CVn,V406 Hya,J0926,J1240,GP Com,Gaia14 aae and V396 Hya.We propose that central spikes in the triple-peaked emission spectra of J1240,GP Com and V396 Hya and the surface abundance ratios of N/C/O in GP Com can be explained by the stable double He WD channel.The mass estimates derived from our calculations are used to discuss the predicted gravitational wave signal in the context of the Laser Interferometer Space Antenna(LISA) project.
基金funded by the State Program of the Ministry of Education and Science of Ukraine (0116U002623)
文摘The magnetoresistive properties of discontinuous ferromagnetic Fe and Co thin films deposited by electron-beam sputtering onto glass substrates at room temperature were investigated. Tunnel magnetoresistance(MR) was observed for all of the as-deposited samples. The maximum MR was observed for Fe thin films with an effective thickness of 17 nm. In the case of the Co thin films, the annealing process led to a change of the type of MR to anisotropic at Co film thicknesses(dCo) of 15 ≤ d_(Co) ≤ 25 nm and to positive isotropic at thicknesses of d_(Co) < 15 nm. By contrast, the MR type of Fe thin films did not change.
基金Supported by the Swedish Natural Science Research Council and the National Natural Science Foundation of China under No 10274025.
文摘Radiative lifetimes of two short-lived levels (i.e. 4f^8 (TF6)6p^1/2 (6, 1/2)11/2,13/2) in Tb Ⅲ are measured by time-resolved laser-induced fluorescence (LIE) technique with a two-step excitation process. Free Tb Ⅲ ions are produced in a laser-induced plasma. Lifetime values are evaluated with a deconvolution procedure of the timeresolved fluorescence signal with the temporal shape of second-step excitation pulse (about 1 ns). The lifetimes of the 4f^8 (^7F6)6p^1/2 (6, 1/2)11/2 and 4f^8(^7F6)6p^1/2 (6, 1/2)13/2 levels are determined to be 1.9 (2) and 2.0 (2)ns, respectively.