The use of non-renewable energy has been a major environmental concern and, therefore, there is a need to look for other renewable energy sources, especially photovoltaic’s. In view of this, an attempt was made to qu...The use of non-renewable energy has been a major environmental concern and, therefore, there is a need to look for other renewable energy sources, especially photovoltaic’s. In view of this, an attempt was made to quantify the potential of solar irradiance in the State of Paraiba, as an alternative source for conversion and use in electrical energy, these determinations being the main objectives. Global solar irradiance and solar photovoltaic data were extracted from scientific publications and/or made available on the websites of the National Institute of Meteorology (INMET), the Ministry of Mines and Energy and the National Electric Energy Agency, among others. For the case study, semi-structured questionnaires were applied in different business establishments in Campina Grande, with questions related to socioeconomic aspects and photovoltaic technology. Data were analyzed using descriptive statistics criteria and using an Excel spreadsheet. The main results indicated that the Brazilian energy matrix is predominantly from renewable sources. The Northeast is the second region with the highest production of photovoltaic solar energy and the State of Paraiba occupies its fourth position in the generation of this type of energy. The option of photovoltaic technology is a promising alternative, especially for rural areas, where there is not always a conventional electricity grid. The high availability of solar energy in northeastern Brazil, in almost all months of the year, especially in the state of Paraiba, demonstrates the existence of a high potential to generate electricity from photovoltaic systems. This technology contributes to local sustainable development, as it is an activity that generates employment and income, without degrading the environment.展开更多
Pretreatment of nerve allografts by exposure to irradiation or green tea polyphenols can elimi- nate neuroimmunogenicity, inhibit early immunological rejection, encourage nerve regeneration and functional recovery, im...Pretreatment of nerve allografts by exposure to irradiation or green tea polyphenols can elimi- nate neuroimmunogenicity, inhibit early immunological rejection, encourage nerve regeneration and functional recovery, improve tissue preservation, and minimize postoperative infection. In the present study, we investigate which intervention achieves better results. We produced a 1.0 cm sciatic nerve defect in rats, and divided the rats into four treatment groups： autograft, fresh nerve allograft, green tea polyphenol-pretreated （1 mg/mL, 4~C） nerve allograft, and irradiation-pre- treated nerve allograft （26.39 Gy/min for 12 hours; total 19 kGy）. The animals were observed, and sciatic nerve electrophysiology, histology, and transmission electron microscopy were carried out at 6 and 12 weeks after grafting. The circumference and structure of the transplanted nerve in rats that received autografts or green tea polyphenol-pretreated nerve allografts were similar to those of the host sciatic nerve. Compared with the groups that received fresh or irradiation-pre- treated nerve allografts, motor nerve conduction velocity in the autograft and fresh nerve allograft groups was greater, more neurites grew into the aUografts, Schwann cell proliferation was evident, and a large number of new blood vessels was observed; in addition, massive myelinated nerve fibers formed, and abundant microfilaments and microtubules were present in the axoplasm. Our findings indicate that nerve allografts pretreated by green tea polyphenols are equivalent to trans- planting autologous nerves in the repair of sciatic nerve defects, and promote nerve regeneration. Pretreatment using green tea polyphenols is better than pretreatment with irradiation.展开更多
As the largest genus of Halymeniaceae,Grateloupia has been widely reported.Here,we observed the life history and early development of Grateloupia constricata Li et Ding and investigated the effects of temperature,irra...As the largest genus of Halymeniaceae,Grateloupia has been widely reported.Here,we observed the life history and early development of Grateloupia constricata Li et Ding and investigated the effects of temperature,irradiance,and photoperiod on the discoid crust and sporeling development of G.constricata under laboratory conditions.We observed that the type of carpospore development was“mediate discal type”.The life history included homotypic gametophyte(haploid),carposporophyte(diploid),and tetrasporophyte(diploid),with typical isomorphic alternation of generations.The results of double factorial analysis showed that both single factorial effects and interaction among temperature,photoperiod,and irradiance were obviously significant on the discoid crust and sporeling development.Furthermore,we found that the optimum combination of condition for the early growth and development of G.constricata was temperature 20°C,irradiance 80μmol photons/(m^2·s)and photoperiod 16L:8D.This study provides the theoretical basis and technical support for the conservation of the Grateloupia germplasm,artificial breeding,large-scale cultivation and sustainable development.展开更多
区域聚焦照射(regional focusing irradiation)能将信号能量准确投送至指定区域,但阵列的超稀疏性使得副瓣区域能量较高,在实施精确电子战时极大增加了干扰系统遭受打击的风险,因此副瓣区域能量抑制问题必须加以解决.本文提出一种基于L...区域聚焦照射(regional focusing irradiation)能将信号能量准确投送至指定区域,但阵列的超稀疏性使得副瓣区域能量较高,在实施精确电子战时极大增加了干扰系统遭受打击的风险,因此副瓣区域能量抑制问题必须加以解决.本文提出一种基于L∞范数评估栅瓣区域能量的方法,将其作为正则项引入区域聚焦照射模型以抑制副瓣区域最大能量,并建立了多目标优化模型.采用交替方向乘子(alternating direction method of multipliers)框架将原问题分解为两个子问题:对于恒模约束下二次规划子问题I,采用贪婪算法给出其闭式解;对于无约束L_(2)⁃L_(∞)范数的子问题II,将L_(∞)范数做近似光滑化处理,并通过梯度下降法求解.交替求解两个子问题至收敛,以求解发射信号.仿真实验表明,本文模型在副瓣区域能量抑制上较基于L1范数的区域聚焦照射模型具有更优性能,且本文算法实用性更强.展开更多
文摘The use of non-renewable energy has been a major environmental concern and, therefore, there is a need to look for other renewable energy sources, especially photovoltaic’s. In view of this, an attempt was made to quantify the potential of solar irradiance in the State of Paraiba, as an alternative source for conversion and use in electrical energy, these determinations being the main objectives. Global solar irradiance and solar photovoltaic data were extracted from scientific publications and/or made available on the websites of the National Institute of Meteorology (INMET), the Ministry of Mines and Energy and the National Electric Energy Agency, among others. For the case study, semi-structured questionnaires were applied in different business establishments in Campina Grande, with questions related to socioeconomic aspects and photovoltaic technology. Data were analyzed using descriptive statistics criteria and using an Excel spreadsheet. The main results indicated that the Brazilian energy matrix is predominantly from renewable sources. The Northeast is the second region with the highest production of photovoltaic solar energy and the State of Paraiba occupies its fourth position in the generation of this type of energy. The option of photovoltaic technology is a promising alternative, especially for rural areas, where there is not always a conventional electricity grid. The high availability of solar energy in northeastern Brazil, in almost all months of the year, especially in the state of Paraiba, demonstrates the existence of a high potential to generate electricity from photovoltaic systems. This technology contributes to local sustainable development, as it is an activity that generates employment and income, without degrading the environment.
基金supported by grants from Research Fund of Lanzhou Military Area Command of Chinese PLA,No.CLZ12JA07Gansu Provincial Science and Technology Program,No.1208RJZA108
文摘Pretreatment of nerve allografts by exposure to irradiation or green tea polyphenols can elimi- nate neuroimmunogenicity, inhibit early immunological rejection, encourage nerve regeneration and functional recovery, improve tissue preservation, and minimize postoperative infection. In the present study, we investigate which intervention achieves better results. We produced a 1.0 cm sciatic nerve defect in rats, and divided the rats into four treatment groups： autograft, fresh nerve allograft, green tea polyphenol-pretreated （1 mg/mL, 4~C） nerve allograft, and irradiation-pre- treated nerve allograft （26.39 Gy/min for 12 hours; total 19 kGy）. The animals were observed, and sciatic nerve electrophysiology, histology, and transmission electron microscopy were carried out at 6 and 12 weeks after grafting. The circumference and structure of the transplanted nerve in rats that received autografts or green tea polyphenol-pretreated nerve allografts were similar to those of the host sciatic nerve. Compared with the groups that received fresh or irradiation-pre- treated nerve allografts, motor nerve conduction velocity in the autograft and fresh nerve allograft groups was greater, more neurites grew into the aUografts, Schwann cell proliferation was evident, and a large number of new blood vessels was observed; in addition, massive myelinated nerve fibers formed, and abundant microfilaments and microtubules were present in the axoplasm. Our findings indicate that nerve allografts pretreated by green tea polyphenols are equivalent to trans- planting autologous nerves in the repair of sciatic nerve defects, and promote nerve regeneration. Pretreatment using green tea polyphenols is better than pretreatment with irradiation.
基金Foundation item: The National Natural Science Foundation of China under contract No. 31570209.
文摘As the largest genus of Halymeniaceae,Grateloupia has been widely reported.Here,we observed the life history and early development of Grateloupia constricata Li et Ding and investigated the effects of temperature,irradiance,and photoperiod on the discoid crust and sporeling development of G.constricata under laboratory conditions.We observed that the type of carpospore development was“mediate discal type”.The life history included homotypic gametophyte(haploid),carposporophyte(diploid),and tetrasporophyte(diploid),with typical isomorphic alternation of generations.The results of double factorial analysis showed that both single factorial effects and interaction among temperature,photoperiod,and irradiance were obviously significant on the discoid crust and sporeling development.Furthermore,we found that the optimum combination of condition for the early growth and development of G.constricata was temperature 20°C,irradiance 80μmol photons/(m^2·s)and photoperiod 16L:8D.This study provides the theoretical basis and technical support for the conservation of the Grateloupia germplasm,artificial breeding,large-scale cultivation and sustainable development.
文摘区域聚焦照射(regional focusing irradiation)能将信号能量准确投送至指定区域,但阵列的超稀疏性使得副瓣区域能量较高,在实施精确电子战时极大增加了干扰系统遭受打击的风险,因此副瓣区域能量抑制问题必须加以解决.本文提出一种基于L∞范数评估栅瓣区域能量的方法,将其作为正则项引入区域聚焦照射模型以抑制副瓣区域最大能量,并建立了多目标优化模型.采用交替方向乘子(alternating direction method of multipliers)框架将原问题分解为两个子问题:对于恒模约束下二次规划子问题I,采用贪婪算法给出其闭式解;对于无约束L_(2)⁃L_(∞)范数的子问题II,将L_(∞)范数做近似光滑化处理,并通过梯度下降法求解.交替求解两个子问题至收敛,以求解发射信号.仿真实验表明,本文模型在副瓣区域能量抑制上较基于L1范数的区域聚焦照射模型具有更优性能,且本文算法实用性更强.
