In this paper,the dynamical evolutions of two types of Arctic Oscillation (AO),the stratospheric (S) and tropospheric (T) types,have been investigated on an intermediate time scale in terms of transient eddy feedback ...In this paper,the dynamical evolutions of two types of Arctic Oscillation (AO),the stratospheric (S) and tropospheric (T) types,have been investigated on an intermediate time scale in terms of transient eddy feedback forcing and three-dimensional Rossby wave propagation.S-Type (T-type) events are characterized by an anomalous stratospheric polar vortex that is in phase (out of phase) with its tropospheric counterpart.Approximately onethird of AO events,both positive and negative,are T-type events.For the positive phase of a T-type event,the formation and maintenance of stratospheric positive anomalies over the polar cap are associated with an upward propagation of Rossby wave packets originating from the near-tropopause altitude over northeastern Asia.However,such upward propagating features are not found for S-type events.In the troposphere,transient eddy feedback forcing is primarily responsible for the meridional seesaw structure of both the S-and T-type events,with an additional contribution from Rossby wave propagation.展开更多
Inflammation of axial and/or peripheral joints is one of the most frequent extra-intestinal manifestations complicating the clinical course and therapeutic approach in inflammatory bowel diseases(IBD).The frequency of...Inflammation of axial and/or peripheral joints is one of the most frequent extra-intestinal manifestations complicating the clinical course and therapeutic approach in inflammatory bowel diseases(IBD).The frequency of these complications seems to be similar for both diseases, Crohn's disease and ulcerative colitis.Arthritis associated with IBD belongs to the category of spondyloarthropathies.Axial involvement ranges from isolated inflammatory back pain to ankylosing spondylitis, whereas peripheral arthritis is noted in pauciarticular and in polyarticular disease.Asymptomatic radiological involvement of the sacroiliac joints is reported to occur in up to 50% of patients.Other musculoskeletal manifestations such as buttock pain, dactylitis, calcaneal enthesitis, and thoracic pain are frequently underdiagnosed and, consequently, are not treated appropriately.Several diagnostic approaches and criteria have been proposed over the past 40 years in an attempt to correctly classify and diagnose such manifestations.The correct recognition of spondylarthropathies needs an integrated multidisciplinary approach in order to identify common therapeutic strategies, especially in the era of the new biologic therapies.展开更多
基金supported by the National Basic Research Program of China (973 Program) under Grant 2009CB421406the National Key Technologies R & D Programof China under Grant 2009BAC51B02
文摘In this paper,the dynamical evolutions of two types of Arctic Oscillation (AO),the stratospheric (S) and tropospheric (T) types,have been investigated on an intermediate time scale in terms of transient eddy feedback forcing and three-dimensional Rossby wave propagation.S-Type (T-type) events are characterized by an anomalous stratospheric polar vortex that is in phase (out of phase) with its tropospheric counterpart.Approximately onethird of AO events,both positive and negative,are T-type events.For the positive phase of a T-type event,the formation and maintenance of stratospheric positive anomalies over the polar cap are associated with an upward propagation of Rossby wave packets originating from the near-tropopause altitude over northeastern Asia.However,such upward propagating features are not found for S-type events.In the troposphere,transient eddy feedback forcing is primarily responsible for the meridional seesaw structure of both the S-and T-type events,with an additional contribution from Rossby wave propagation.
文摘Inflammation of axial and/or peripheral joints is one of the most frequent extra-intestinal manifestations complicating the clinical course and therapeutic approach in inflammatory bowel diseases(IBD).The frequency of these complications seems to be similar for both diseases, Crohn's disease and ulcerative colitis.Arthritis associated with IBD belongs to the category of spondyloarthropathies.Axial involvement ranges from isolated inflammatory back pain to ankylosing spondylitis, whereas peripheral arthritis is noted in pauciarticular and in polyarticular disease.Asymptomatic radiological involvement of the sacroiliac joints is reported to occur in up to 50% of patients.Other musculoskeletal manifestations such as buttock pain, dactylitis, calcaneal enthesitis, and thoracic pain are frequently underdiagnosed and, consequently, are not treated appropriately.Several diagnostic approaches and criteria have been proposed over the past 40 years in an attempt to correctly classify and diagnose such manifestations.The correct recognition of spondylarthropathies needs an integrated multidisciplinary approach in order to identify common therapeutic strategies, especially in the era of the new biologic therapies.
