286 research outputs found
Double -rescaling model and the nuclear effect of the parton distribution functions
In order to overcome the shortcoming of nonconservation of nuclear momentum
existing in the original -rescaling model(ORM) and avoid introducing
nuclear shadowing factor, we proposed a double -rescaling model(DRM)
for the parton distributions of the bound nucleon. Using the experimental data
of lepton-nucleus deep inelastic scattering(DIS) and the condition of the
nuclear momentum conservation, the -rescaling parameters of various
partons for Sn, Fe, Ca and C nuclei are determined. The rescaling parameters of
valence quark distributions are larger than unity and graduauly increases with
atomic number A, on the contrary, the rescaling parameters of sea quark
distributions and gluon distributions are smaller than unity, and slowly
decreases with A. By using this model, the experimental data of the DIS
process, the nuclear Drell-Yan process and photoproduction process are
consistently and quite satisfactorily explained. Key words --- parton
distribution functions, Nuclear effect, Double -rescaling model.Comment: 15 pages, 4 figures (to be published in Z. Phys. C
ダイ1ジ エットウタイ ノ ソリイヌ ノ カンリ ト イヌゾリ リョコウ
(1)第1次越冬隊に使用させていただいた犬ぞりは,その準備と訓練に多大の努力を払って下さった加納一郎氏,北海道大学の犬飼哲夫教授,芳賀良一講師など,北大極地研究グループの人達に負う処が極めて大であった.厚く御礼申し上げる.(2)南極や北極で,外国隊の使用した犬はすべてハスキー種(又はその同属)であるが,日本隊は,1910~12年の白瀬隊の時もそうであった様に,今回も樺太犬を使用した.(3)越冬した樺太犬は,越冬初期に19頭(内雌1頭)であったが,越冬中に3頭をなくし,8頭の仔犬が産まれたので,その末期には24頭(雌1頭,仔犬8頭を合む)であった.この内,15頭の雄成犬が,第2次越冬隊を待ったまま昭和基地に残った.(4)IIの項では,昭和基地の犬小屋,犬の食糧(第1表),犬の体重変化(第2表),仔犬の出産及び8月に行なった訓練(第3表)について書いた.(5)IIIの項では,始めにそりその他の用具についてふれ,続いて,パッダ島並びにその南の上陸地点への偵察行(8月28日~9月4日),ボツンヌーテン行(10月16日~11月11日)及びオラフ行(11月25日~12月10日)の3つの旅行をあげ、それぞれ第4表,第5表,第6表にその概要を記した.(6)犬ぞり旅行を,数字で説明する一つの試みとして,Wt=(4rtfgaWdN)/V(荷重の法則)なる式を仮定し,3つの旅行について,その分析を行なった.第7表,第8表,第9表に示す通りである.(7)15顛の犬達が,オングル島に残らざるを得なかったのは,実現はしなかった第2次越冬隊を送り込む事に最大の努力がはらわれ,犬達は新しい隊の来るのを待っていたのである事実を明記した.(8)最後に犬達の冥福を心から祈って,この拙い報告書を彼等の霊に棒げる
Effect of different trunk postures on scapular muscle activities and kinematics during shoulder external rotation
[Background]Shoulder external rotation at abduction (ER) is a notable motion in overhead sports because it could cause strong stress to the elbow and shoulder joint. However, no study has comprehensively investigated the effect of different trunk postures during ER. This study aimed to investigate the effect of different trunk postures on scapular kinematics and muscle activities during ER. [Methods]Fourteen healthy men performed active shoulder external rotation at 90° of abduction with the dominant arm in 15 trunk postures. At maximum shoulder external rotation in 15 trunk postures, including 4 flexion-extension, 6 trunk rotation, and 4 trunk side-bending postures, as well as upright posture as a control, scapular muscle activities and kinematics were recorded using surface electromyography and an electromagnetic tracking device, respectively. The data obtained in the flexion-extension, trunk rotation, and trunk side-bending postures were compared with those obtained in the upright posture. [Results]In the flexion-extension condition, scapular posterior tilt and external rotation significantly decreased, but the muscle activities of the lower trapezius and infraspinatus significantly increased in maximum trunk flexion. Moreover, scapular upward rotation and the activity of the serratus anterior significantly increased in maximum trunk extension. In the rotation condition, scapular posterior tilt and external rotation significantly decreased, but the activity of the serratus anterior significantly increased in the maximum contralateral trunk rotation posture. In the trunk side-bending condition, scapular posterior tilt and the external rotation angle significantly decreased. [Conclusio]Trunk postures affected scapular kinematics and muscle activities during ER. Our results suggest that different trunk postures activate the lower trapezius and serratus anterior, which induce scapular posterior tilt
Targeting of MIST to Src-family kinases via SKAP55–SLAP-130 adaptor complex in mast cells11The rat SKAP55 cDNA nucleotide sequence has been deposited in DDBJ database under accession number AB092812.
AbstractMIST (mast cell immunoreceptor signal transducer; also termed Clnk) is an adaptor protein structurally related to SLP-76-family hematopoietic cell-specific adaptor proteins. We demonstrate here that two major MIST-associated phosphoproteins expressed in mast cell lines are SLAP-130 and SKAP55, adaptors known to interact with the Src-homology (SH) 2 domain of Src-family protein tyrosine kinases (PTKs). MIST directly associated with SLAP-130 via its SH2 domain, and collaboration of SLAP-130 with SKAP55 was required for the recruitment of MIST to Lyn. Furthermore, MIST was preferentially recruited to Fyn rather than Lyn, which is regulated by higher affinity binding of SLAP-130 and SKAP55 with the Fyn-SH2 domain than the Lyn-SH2 domain. Our results suggest that the MIST–SLAP-130–SKAP55 adaptor complex functions downstream of high-affinity IgE receptor-associated Src-PTKs in mast cells
Effects of periodic robot rehabilitation using the Hybrid Assistive Limb for a year on gait function in chronic stroke patients
Using a robot for gait training in stroke patients has attracted attention for the last several decades. Previous studies reported positive effects of robot rehabilitation on gait function in the short term. However, the long-term effects of robot rehabilitation for stroke patients are still unclear. The purpose of the present study was to investigate the long-term effects of periodic gait training using the Hybrid Assistive Limb (HAL) on gait function in chronic stroke patients. Seven chronic stroke patients performed 8 gait training sessions using the HAL 3 times every few months. The maximal 10-m walk test and the 2-minute walking distance (2MWD) were measured before the first intervention and after the first, second, and third interventions. Gait speed, stride length, and cadence were calculated from the 10-m walk test. Repeated one-way analysis of variance showed a significant main effect on evaluation time of gait speed (F = 7.69, p < 0.01), 2MWD (F = 7.52, p < 0.01), stride length (F = 5.24, p < 0.01), and cadence (F = 8.43, p < 0.01). The effect sizes after the first, second, and third interventions compared to pre-intervention in gait speed (d = 0.39, 0.52, and 0.59) and 2MWD (d = 0.35, 0.46, and 0.57) showed a gradual improvement of gait function at every intervention. The results of the present study showed that gait function of chronic stroke patients improved over a year with periodic gait training using the HAL every few months
Accuracy of Nonlinear Interference Estimation on Launch Power Optimization in Short-Reach Systems with Field Trial
We show that even the approximate formula of the Gaussian noise model is accurate enough for launch power optimization in short-reach systems. We compare simulation and field trial results using two fiber types, showing the estimation error of signal Q-factor is less than 0.02 dB
A Point Mutation of Tyr-759 in Interleukin 6 Family Cytokine Receptor Subunit gp130 Causes Autoimmune Arthritis
We generated a mouse line in which the src homology 2 domain–bearing protein tyrosine phosphatase (SHP)-2 binding site of gp130, tyrosine 759, was mutated to phenylalanine (gp130F759/F759). The gp130F759/F759 mice developed rheumatoid arthritis (RA)-like joint disease. The disease was accompanied by autoantibody production and accumulated memory/activated T cells and myeloid cells. Before the disease onset, the T cells were hyperresponsive and thymic selection and peripheral clonal deletion were impaired. The inhibitory effect of IL-6 on Fas ligand expression during activation-induced cell death (AICD) was augmented in gp130F759/F759 T cells in a manner dependent on the tyrosine residues of gp130 required for signal transducer and activator of transcription 3 activation. Finally, we showed that disease development was dependent on lymphocytes. These results provide evidence that a point mutation of a cytokine receptor has the potential to induce autoimmune disease
Involvement of Bruton's Tyrosine Kinase in FcεRI-dependent Mast Cell Degranulation and Cytokine Production
We investigated the role of Bruton's tyrosine kinase (Btk) in FcεRI-dependent activation of mouse mast cells, using xid and btk null mutant mice. Unlike B cell development, mast cell development is apparently normal in these btk mutant mice. However, mast cells derived from these mice exhibited significant abnormalities in FcεRI-dependent function. xid mice primed with anti-dinitrophenyl monoclonal IgE antibody exhibited mildly diminished early-phase and severely blunted late-phase anaphylactic reactions in response to antigen challenge in vivo. Consistent with this finding, cultured mast cells derived from the bone marrow cells of xid or btk null mice exhibited mild impairments in degranulation, and more profound defects in the production of several cytokines, upon FcεRI cross-linking. Moreover, the transcriptional activities of these cytokine genes were severely reduced in FcεRI-stimulated btk mutant mast cells. The specificity of these effects of btk mutations was confirmed by the improvement in the ability of btk mutant mast cells to degranulate and to secrete cytokines after the retroviral transfer of wild-type btk cDNA, but not of vector or kinase-dead btk cDNA. Retroviral transfer of Emt (= Itk/Tsk), Btk's closest relative, also partially improved the ability of btk mutant mast cells to secrete mediators. Taken together, these results demonstrate an important role for Btk in the full expression of FcεRI signal transduction in mast cells
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