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1.
Phys Rev Lett ; 131(8): 082501, 2023 Aug 25.
Artigo em Inglês | MEDLINE | ID: mdl-37683162

RESUMO

The nuclear incompressibility is a key parameter of the nuclear equation of state that can be extracted from the measurements of the so-called "breathing mode" of finite nuclei. The most serious discrepancy so far is between values extracted from Pb and Sn, that has provoked the longstanding question "Why is tin so soft?". To solve this puzzle, a fully self-consistent quasiparticle random-phase approximation plus quasiparticle-vibration coupling approach based on Skyrme-Hartree-Fock-Bogoliubov is developed. We show that the many-body correlations introduced by quasiparticle-vibration coupling, which shift the isoscalar giant monopole resonance energy in Sn isotopes by about 0.4 MeV more than the energy in ^{208}Pb, play a crucial role in providing a unified description of the isoscalar giant monopole resonance in Sn and Pb isotopes. The best description of the experimental strength functions is given by SV-K226 and KDE0, which are characterized by incompressibility values K_{∞}=226 MeV and 229 MeV, respectively, at mean field level.

2.
Phys Rev Lett ; 130(19): 192501, 2023 May 12.
Artigo em Inglês | MEDLINE | ID: mdl-37243656

RESUMO

Using a novel method of isochronous mass spectrometry, the masses of ^{62}Ge, ^{64}As, ^{66}Se, and ^{70}Kr are measured for the first time, and the masses of ^{58}Zn, ^{61}Ga, ^{63}Ge, ^{65}As, ^{67}Se, ^{71}Kr, and ^{75}Sr are redetermined with improved accuracy. The new masses allow us to derive residual proton-neutron interactions (δV_{pn}) in the N=Z nuclei, which are found to decrease (increase) with increasing mass A for even-even (odd-odd) nuclei beyond Z=28. This bifurcation of δV_{pn} cannot be reproduced by the available mass models, nor is it consistent with expectations of a pseudo-SU(4) symmetry restoration in the fp shell. We performed ab initio calculations with a chiral three-nucleon force (3NF) included, which indicate the enhancement of the T=1 pn pairing over the T=0 pn pairing in this mass region, leading to the opposite evolving trends of δV_{pn} in even-even and odd-odd nuclei.

3.
Cryo Letters ; 39(1): 39-44, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-29734413

RESUMO

  The survival of porcine oocytes is still very low after cryopreservation. OBJECTIVE: To investigate whether and when the mitochondrial function of vitrified porcine oocytes could be recovered post-thaw. MATERIALS AND METHODS: Mitochondrial potential, ROS level, ATP content, apoptotic rate, caspase activity, and parthenogenetics developmental ability of thawed porcine oocytes were measured after culture in vitro for 0, 1, 2 or 4 h. RESULTS: Mitochondrial potential after 2 h and 4 h post-thaw culture were 1.19 and 1.26, significantly lower than that of fresh oocytes but much higher than the groups cultured for 0 h and 1 h (P<0.05). Cryopreservation increased the ROS level in oocytes considerably, which decreased only after 2 to 4 h incubation following thaw. ATP content increased gradually over time and recovered to the level comparable to that of fresh oocytes after 4 h. Pan caspase levels increased after cryopreservation and reached the highest level at 1 h incubation. Thereafter it decreased to a low value, but still higher than fresh oocytes. Oocytes showing an early apoptotic event decreased upon 2 to 4 h incubation. The parthenogenetic cleavage and blastocyst rates were the highest (19.8% and 5.6%) after 2 h incubation. CONCLUSION: The recovery of mitochondrial function could complete after 2 to 4 h post-thaw incubation. Post-thaw incubation for 2 to 4 h reduced apoptotic events and improved parthenogenetic developmental ability of vitrified porcine MII stage oocytes.


Assuntos
Congelamento , Metáfase , Mitocôndrias/metabolismo , Oócitos/fisiologia , Vitrificação , Trifosfato de Adenosina/metabolismo , Animais , Apoptose , Sobrevivência Celular , Criopreservação , Feminino , Espaço Intracelular/metabolismo , Potencial da Membrana Mitocondrial , Espécies Reativas de Oxigênio/metabolismo , Sus scrofa
4.
Cryo Letters ; 37(2): 129-36, 2016.
Artigo em Inglês | MEDLINE | ID: mdl-27224525

RESUMO

BACKGROUND: Oocytes vitrification is widely used for cryopreservation of female genetic resources. OBJECTIVE: In order to illuminate the apoptotic pathways of porcine MII stage oocytes after vitrification. MATERIALS AND METHODS: This study used in situ fluorescence staining and RT-PCR to detect the expression levels of some key molecules from death receptor and mitochondria mediated apoptotic pathways. RESULTS: (1) Early stage apoptosis were detected in both PI staining survival oocytes and PI staining dead oocytes. (2) The fluorescence intensity of caspase 8, caspase 9, caspase 3 and pan caspase from vitrified oocytes were 32.03, 16.56, 16.70 and 8.43 respectively, which were much higher than those from fresh oocytes (4.02, 4.83, 4.23 and 3.08, P < 0.05). (3) Not only the genes from death receptor mediated apoptotic pathway, but also from mitochondrial mediated apoptotic pathway were changed greatly. CONCLUSION: The death of porcine vitrified oocytes could be induced by apoptosis, both death receptor and mitochondria mediated apoptotic pathways participated the occurrence of apoptosis in porcine vitrified MII stage oocytes.


Assuntos
Apoptose , Criopreservação/veterinária , Oócitos , Sus scrofa/fisiologia , Vitrificação , Animais , Criopreservação/métodos , Feminino , Hibridização in Situ Fluorescente/veterinária , Mitocôndrias/metabolismo , Reação em Cadeia da Polimerase/veterinária , Receptores de Morte Celular/genética , Receptores de Morte Celular/metabolismo
5.
Phys Rev Lett ; 114(14): 142501, 2015 Apr 10.
Artigo em Inglês | MEDLINE | ID: mdl-25910114

RESUMO

Nuclear ß decay in magic nuclei is investigated, taking into account the coupling between particles and collective vibrations, on top of self-consistent random phase approximation calculations based on Skyrme density functionals. The low-lying Gamow-Teller strength is shifted downwards and at times becomes fragmented; as a consequence, the ß-decay half-lives are reduced due to the increase of the phase space available for the decay. In some cases, this leads to a very good agreement between theoretical and experimental lifetimes: this happens, in particular, in the case of the Skyrme force SkM* that can also reproduce the line shape of the high-energy Gamow-Teller resonance as was previously shown.

6.
Eur Rev Med Pharmacol Sci ; 17(14): 1951-7, 2013 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-23877861

RESUMO

BACKGROUND: Iliac bone graft harvesting is a common procedure in spinal surgery and trauma center for spinal fusion and nonunion of the extremities. AIM, PATIENTS AND METHODS: To compare the pain and cosmetic outcomes of patients undergoing iliac crest anatomical reconstruction using equivalent iliac crest allograft (R group) with those of patients without reconstruction of the iliac crest defect (NR group), a prospective nonrandomized controlled study was conducted. RESULTS: In R group, the intensity and prevalence of pain were significantly lower than those in NR group. Cosmetic outcome and satisfaction score were also significantly improved in R group. One patient of R group suffered from lipolysis and superficial infection which healed by regular dressing change for two weeks. There were no cases of allograft displacement, implant loosening, internal fixation breakage or immunological rejection. Seven patients in NR group had significant pain related to the tenting of skin over the defect. Radiologic incorporation of pelvis was documented in all patients except four having partial re-sorption of the allograft. Early fibrous healing and the late creeping substitution were noted in all patients of R group. CONCLUSIONS: Equivalent iliac crest allograft provides an effective alternative for iliac crest anatomical reconstruction, leading to reduced donor site pain and better cosmesis.


Assuntos
Ílio/anatomia & histologia , Ílio/transplante , Sítio Doador de Transplante/anatomia & histologia , Adolescente , Adulto , Transplante Ósseo/efeitos adversos , Avaliação da Deficiência , Feminino , Humanos , Ílio/diagnóstico por imagem , Masculino , Pessoa de Meia-Idade , Medição da Dor , Dor Pós-Operatória/epidemiologia , Estudos Prospectivos , Radiografia , Fusão Vertebral , Sítio Doador de Transplante/diagnóstico por imagem , Resultado do Tratamento
7.
Genet Mol Res ; 10(4): 3427-34, 2011 Oct 21.
Artigo em Inglês | MEDLINE | ID: mdl-22033900

RESUMO

Genetic transformation is useful for basic research and applied biotechnology. However, genetic transformation of microalgae is usually quite difficult due to the technical limitations of existing methods. We cloned the promoter and terminator of the nitrate reductase gene from the microalga Phaeodactylum tricornutum and used them for optimization of a transformation system of the microalga Chlorella vulgaris. This species has been used for food production and is a promising candidate as a bioreactor for large-scale production of value-added proteins. A construct was made containing the CAT (chloramphenicol acetyltransferase) reporter gene driven by the nitrate reductase promoter. This construct was transferred into the C. vulgaris genome by electroporation. Expression of CAT in transgenic Chlorella conferred resistance to the antibiotic chloramphenicol and enabled growth in selective media. Overall efficiency for the transformation was estimated to be approximately 0.03%, which is relatively high compared with other available Chlorella transformation systems. Expression of CAT was induced in the presence of nitrate and inhibited in the presence of ammonium as a sole nitrogen source. This study presented an inducible recombinant gene expression system, also providing more gene regulation elements with potential for biotechnological applications.


Assuntos
Chlorella vulgaris/genética , Expressão Gênica , Transformação Genética , Cloranfenicol/farmacologia , Cloranfenicol O-Acetiltransferase/genética , Resistência ao Cloranfenicol/genética , Chlorella vulgaris/efeitos dos fármacos , Chlorella vulgaris/enzimologia , Expressão Gênica/efeitos dos fármacos , Vetores Genéticos/genética , Nitrato Redutase/genética , Nitratos/farmacologia , Organismos Geneticamente Modificados , Reação em Cadeia da Polimerase , Regiões Promotoras Genéticas/genética , Seleção Genética , Transformação Genética/efeitos dos fármacos
8.
Zhonghua Liu Xing Bing Xue Za Zhi ; 37(8): 1108-11, 2016 Aug 10.
Artigo em Zh | MEDLINE | ID: mdl-27539342

RESUMO

OBJECTIVE: To explore the yearly, monthly and habitat-related distribution and their relations with Meriones unguiculatus density in the Hebei Meriones unguiculatus plague foci, from 2001 to 2013. METHODS: Data related to Meriones unguiculatus was gathered through the monitoring programs set up at the national and provincial Meriones unguiculatus plague foci in Hebei province, from 2001 to 2013. According to the yearly density of Meriones unguiculatus, criteria set for the three groups under study, were as follows:'high-risk group'-when the rodent density was≥1.00 under rodents/hm(2),'warning group'-when the rodents/hm(2)>rodent density> 0.20,'standard group'-when rodents/hm(2) rodent density≤0.20 rodents/hm(2). Differences of habitats and monthly distribution among the three groups were compared, under the Kruskal-Wallis H rank sum test while their relations were under the multiple correspondence analysis. RESULTS: The Meriones unguiculatus densities were higher than 1.00 rodents/hm(2), far above the set national standards, in the monitoring area, between 2001 and 2005. From 2005, though the rodent densities began to decrease, however, figures from 2008 to 2013 were still among 0.20 to 1.00 rodents/hm(2). The distribution of habitats in the three groups showed that the Meriones unguiculatus densities were all different in habitats and the difference was statistically significant (P<0.05). The highest median densities were all in the arable land, with maximum value of high-risk group appeared the highest (20.50 rodents/hm(2)) in the wasteland. Monthly distribution showed that the Meriones unguiculatus densities were different and the difference was statistically significant (P<0.05) in the high-risk and standard groups but not statistically significant in the warning group. Data from the multiple correspondence analysis showed that there was a strong aggregation among wasteland, in April and June, while the warning group was associated with weather in July and the arable land. CONCLUSIONS: When the density became higher than 1.00 rodents/hm(2), the risk on animal plague increased in Hebei Meriones unguiculatus plague foci. Based on the distribution of Meriones unguiculatus, programs should be set to monitor the rodent in arable land and wasteland, in April and June, to reduce the prevalence of animals plague.


Assuntos
Gerbillinae , Peste , Animais , China/epidemiologia , Peste/epidemiologia , Prevalência , Roedores , Vigilância de Evento Sentinela , Tempo (Meteorologia)
9.
Peptides ; 15(8): 1505-11, 1994.
Artigo em Inglês | MEDLINE | ID: mdl-7700853

RESUMO

Tyr-W-MIF-1 is a tetrapeptide recently isolated from brain that has opiate modulating activity. In this study, we used immunocytochemical (ICC) detection of FOS proto-oncogene protein to map brain areas activated by an ICV injection of Tyr-W-MIF-1 (200 micrograms). The analgesic effect of the peptide, which lasted 1 h, was confirmed in each rat with the tail flick test. FOS was activated in several limbic structures, including the cingulate and infralimbic cortex, nucleus accumbens, and central nucleus of the amygdala. FOS activation also occurred in several diencephalic nuclei, including the supraoptic, paraventricular, and periventricular nuclei of the hypothalamus, and the paraventricular nucleus of the thalamus. Several activated areas contained mu-opiate receptors. However, despite the known selectivity of Tyr-W-MIF-1 for mu receptors, FOS immunoreactivity was also induced in nuclei of the amygdala, hypothalamus, and thalamus, where concentrations of kappa receptors were high but those of mu and delta receptors were not detected. The results show that Tyr-W-MIF-1 induces FOS activation in several brain areas, including but not limited to, areas associated with nociception and stress-induced analgesia.


Assuntos
Encéfalo/metabolismo , Ventrículos Cerebrais/fisiologia , Expressão Gênica , Hormônio Inibidor da Liberação de MSH/análogos & derivados , Antagonistas de Entorpecentes/farmacologia , Proteínas Proto-Oncogênicas c-fos/biossíntese , Analgesia , Animais , Encéfalo/citologia , Encéfalo/efeitos dos fármacos , Ventrículos Cerebrais/efeitos dos fármacos , Imuno-Histoquímica , Injeções Intraventriculares , Hormônio Inibidor da Liberação de MSH/administração & dosagem , Hormônio Inibidor da Liberação de MSH/farmacologia , Masculino , Especificidade de Órgãos , Ratos , Ratos Sprague-Dawley , Valores de Referência
10.
Plant Signal Behav ; 6(9): 1414-7, 2011 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-21847031

RESUMO

This review highlights a potential signaling pathway of CO2-dependent stimulation in root hair development. Elevated CO2 firstly increases the carbohydrates production, which triggers the auxin or ethylene responsive signal transduction pathways and subsequently stimulates the generation of intracellular nitric oxide (NO). The NO acts on target Ca2+ and ion channels and induces activation of MAPK. Meanwhile, reactive oxygen species (ROS) activates cytoplasmic Ca2+ channels at the plasma membrane in the apex of the root tip. This complex pathway involves transduction cascades of multiple signals that lead to the fine tuning of epidermal cell initiation and elongation. The results suggest that elevated CO2 plays an important role in cell differentiation processes at the root epidermis.


Assuntos
Arabidopsis/efeitos dos fármacos , Arabidopsis/crescimento & desenvolvimento , Dióxido de Carbono/farmacologia , Raízes de Plantas/efeitos dos fármacos , Raízes de Plantas/crescimento & desenvolvimento , Arabidopsis/metabolismo , Cálcio/metabolismo , Etilenos/metabolismo , Ácidos Indolacéticos/metabolismo , Raízes de Plantas/metabolismo , Espécies Reativas de Oxigênio/metabolismo
11.
Phys Rev Lett ; 103(3): 032502, 2009 Jul 17.
Artigo em Inglês | MEDLINE | ID: mdl-19659271

RESUMO

The electric-dipole response of 140Ce is investigated using the fully consistent relativistic quasiparticle random phase approximation. By analyzing the isospin structure of the E1 response, it is shown that the low-energy (pygmy) strength separates into two segments with different isospin character. The more pronounced pygmy structure at lower energy is composed of predominantly isoscalar states with surface-peaked transition densities. At somewhat higher energy the calculated E1 strength is primarily of isovector character, as expected for the low-energy tail of the giant dipole resonance. The results are in qualitative agreement with those obtained in recent (gamma, gamma') and (alpha, alpha'gamma) experiments, and provide a simple explanation for the splitting of low-energy E1 strength into two groups of states with different isospin structure and radial dependence of the corresponding transition densities.

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