A mathematical energy coupling model was developed to analyze the light transmission in the keyhole and energy distribution on the keyhole wall.The main characteristics of the model include：1） a prototype of the key...A mathematical energy coupling model was developed to analyze the light transmission in the keyhole and energy distribution on the keyhole wall.The main characteristics of the model include：1） a prototype of the keyhole and the inverse Bremsstrahlung absorption coefficient in the keyhole plasma are obtained from the experiments;2） instead of using a parallel incident beam,a focused laser beam with real Gaussian intensity distribution is implemented;3） both Fresnel absorption and inverse Bremsstrahlung absorption during multiple reflections are considered.The calculation results show that the distribution of absorbed laser intensity by the keyhole wall is not uniform.The maximum laser energy is absorbed by the bottom of the keyhole,although no rays irradiate directly onto the bottom.According to analysis of beam focusing characteristics,the location of the focal plane plays a more important role in the laser energy absorption by the front wall than by the rear wall.展开更多
A number of new, novel strategies for managing constipation in the elderly have emerged over the past few years. Prucalopride is one such new agent that is highly effi cacious in managing chronic constipation. In fact...A number of new, novel strategies for managing constipation in the elderly have emerged over the past few years. Prucalopride is one such new agent that is highly effi cacious in managing chronic constipation. In fact, Camilleri et al in a recent study reported that the average number of bowel movements increased by at least one in nearly 47% of the patients who were administered a dose of 4 mg. Lubiprostone is another new agent recently approved by the FDA that shows efficacy in managing the symptoms of constipation. Neostigmine has also been successfully used for the management of recalcitrant constipation. Most of these studies have used subcutaneous neostigmine. Symbiotic yogurt containig components, such as Bifidobacterium and fructoligosaccharide, have also been recently shown to be highly effective in improving symptoms of constipation. Elderly patients especially those in hospices and nursing homes are often on opiods for pain management. Constipation secondary to opioid use is extremely common in nursing homes. Subcutaneous methylnaltrexone has recently been shown to be highly effective in the management of opioid-related constipation, and was recently approved by the FDA. Sacral nerve stimulation is another emerging strategy. A recent analysis by Mowatt et al supports the eff icacy of this technique. Botulinum toxin is another agent that has already been successfully used for the management of chronic, refractory constipation in children and may be very effective for elderly constipation. Further larger studies are needed to confi rm the fi ndings noted in these studies. Constipation is clearly a major issue in the elderly and these new, emerging strategies will hopefully improve the quality of life and relieve the symptoms of constipation in this population.展开更多
Let （R, A） be a commutative form ring. We obtain a complete description of all subgroups of quadratic groups Q2n（R, A） which are normalized by elementary subgroups by form ideals, rather than usual ideals. For the...Let （R, A） be a commutative form ring. We obtain a complete description of all subgroups of quadratic groups Q2n（R, A） which are normalized by elementary subgroups by form ideals, rather than usual ideals. For the weak sandwich theorem, we give a direct proof without using localization method.展开更多
基金Projects (51175162, 50805045) supported by the National Natural Science Foundation of ChinaProject supported by the Scientific Research Foundation for the Returned Overseas Chinese Scholars,Ministry of Education,China
文摘A mathematical energy coupling model was developed to analyze the light transmission in the keyhole and energy distribution on the keyhole wall.The main characteristics of the model include：1） a prototype of the keyhole and the inverse Bremsstrahlung absorption coefficient in the keyhole plasma are obtained from the experiments;2） instead of using a parallel incident beam,a focused laser beam with real Gaussian intensity distribution is implemented;3） both Fresnel absorption and inverse Bremsstrahlung absorption during multiple reflections are considered.The calculation results show that the distribution of absorbed laser intensity by the keyhole wall is not uniform.The maximum laser energy is absorbed by the bottom of the keyhole,although no rays irradiate directly onto the bottom.According to analysis of beam focusing characteristics,the location of the focal plane plays a more important role in the laser energy absorption by the front wall than by the rear wall.
文摘A number of new, novel strategies for managing constipation in the elderly have emerged over the past few years. Prucalopride is one such new agent that is highly effi cacious in managing chronic constipation. In fact, Camilleri et al in a recent study reported that the average number of bowel movements increased by at least one in nearly 47% of the patients who were administered a dose of 4 mg. Lubiprostone is another new agent recently approved by the FDA that shows efficacy in managing the symptoms of constipation. Neostigmine has also been successfully used for the management of recalcitrant constipation. Most of these studies have used subcutaneous neostigmine. Symbiotic yogurt containig components, such as Bifidobacterium and fructoligosaccharide, have also been recently shown to be highly effective in improving symptoms of constipation. Elderly patients especially those in hospices and nursing homes are often on opiods for pain management. Constipation secondary to opioid use is extremely common in nursing homes. Subcutaneous methylnaltrexone has recently been shown to be highly effective in the management of opioid-related constipation, and was recently approved by the FDA. Sacral nerve stimulation is another emerging strategy. A recent analysis by Mowatt et al supports the eff icacy of this technique. Botulinum toxin is another agent that has already been successfully used for the management of chronic, refractory constipation in children and may be very effective for elderly constipation. Further larger studies are needed to confi rm the fi ndings noted in these studies. Constipation is clearly a major issue in the elderly and these new, emerging strategies will hopefully improve the quality of life and relieve the symptoms of constipation in this population.
基金supported by National Natural Science Foundation of China(Grant No.10871011)
文摘Let （R, A） be a commutative form ring. We obtain a complete description of all subgroups of quadratic groups Q2n（R, A） which are normalized by elementary subgroups by form ideals, rather than usual ideals. For the weak sandwich theorem, we give a direct proof without using localization method.
