Acarbose, a potent α-glucosidase inhibitor, is widely used as an oral anti-diabetic drug for the treatment of the type 2, non-insulin-dependent diabetes. In this work, a gel type strong acid cation exchange resin 001...Acarbose, a potent α-glucosidase inhibitor, is widely used as an oral anti-diabetic drug for the treatment of the type 2, non-insulin-dependent diabetes. In this work, a gel type strong acid cation exchange resin 001×4 was applied to isolate acarbose from fermentation broth. It was demonstrated that cation exchanger 001×4 displayed a large adsorption capacity and quick exchange rate for acarbose. The static adsorption equilibrium data were well fitted to the Langmuir equation. Column adsorption experiments demonstrated that high dynamic adsorption capacity was reached at bed height of 104.4 mm, feed flow rate of 1.0 ml·min 1and acarbose concentration of 4.0 mg·ml 1.Under the optimized conditions, the column chromatography packed with cation exchanger 001×4 recovered 74.3%(by mass) of acarbose from Actinoplanes utahensis ZJB-08196 fermentation broth with purity of 80.1%(by mass),demonstrating great potential in the practical applications in acarbose separation.展开更多
Jiu Ai Tu(The Moxa Treatment)from the Song dynasty is the earliest surviving painting that focuses on the subject of acupuncture and moxibustion.This paper takes the medical activities depicted in the artwork as its r...Jiu Ai Tu(The Moxa Treatment)from the Song dynasty is the earliest surviving painting that focuses on the subject of acupuncture and moxibustion.This paper takes the medical activities depicted in the artwork as its research object and systematically analyzes the external treatment methods for abscesses during the Song dynasty reflected in Jiu Ai Tu.By examining the understanding of abscesses during that period,the paper explores the level of development in external medicine techniques.By analyzing the medical awareness and behaviors of patients when facing such severe illnesses,it aims to explore the societal cognition and experiences regarding health and disease.The paper attempts to present the folk medical ecology of the Song dynasty represented by Jiu Ai Tu.展开更多
BACKGROUND The waist-to-height ratio(WHtR)is a promising anthropometric measure used to evaluate cardiovascular risk in diabetes and metabolic syndrome patients.The metformin and acarbose in Chinese as the initial hyp...BACKGROUND The waist-to-height ratio(WHtR)is a promising anthropometric measure used to evaluate cardiovascular risk in diabetes and metabolic syndrome patients.The metformin and acarbose in Chinese as the initial hypoglycaemic treatment trial demonstrated that acarbose and metformin reduced the WHtR after 24 wk of treatment.AIM To investigate the factors associated with a decrease in the WHtR in newly diagnosed Chinese type 2 diabetes patients receiving acarbose or metformin monotherapy.METHODS At 24 wk,343 patients in the acarbose treatment and 333 patients in the metformin treatment were included in this analysis.On the basis of the reduction in the WHtR,these participants were divided into the following two groups:LowΔWHtR group and highΔWHtR group.Metabolic and related parameters associated with a highΔWHtR were investigated using univariate and multivariate logistic regression analyses.RESULTS A significant decrease in the WHtR was observed in both treatment groups(acarbose:-0.015,95%confidence interval[CI]:-0.018 to-0.012,P<0.001;metformin:-0.013,95%CI:-0.016 to-0.010,P<0.001).In both the acarbose and metformin groups,the WHtR of the women was more likely to be reduced than that of the men.In the acarbose group,a lower baseline area under the curve of glucagon-like peptide 1(AUCGLP-1)was associated with a highΔWHtR(odds ratio[OR]=0.796,P<0.001),while a higher baseline AUCGLP-1 was associated with a highΔWHtR in the patients treated with metformin(OR=1.133,P=0.025).Regarding the changes from baseline,an increase in AUCGLP-1 was associated with a highΔWHtR in the acarbose(OR=1.121,P=0.016)but not metformin group.A higher reduction in high-density lipoprotein cholesterol/non-highdensity lipoprotein cholesterol was also associated with a highΔWHtR in the acarbose arm(OR=20.735,P=0.001).In the metformin arm,a higher reduction in fasting plasma glucose(OR=0.843,P=0.039)and total cholesterol was associated with a highΔWHtR(OR=0.743,P=0.013).CONCLUSION A lower glucagon-like peptide 1 level and higher increase in glucagon-like peptide 1 are associated with a high reduction in the WHtR in newly diagnosed Chinese diabetes patients receiving treatment with acarbose.展开更多
Acarbose is used to control postpran-dial blood glucose in patients with type 2 diabetes and impaired glucose tolerance,since it improves insulin resistance and reduces blood lipids and cardiovascular complications.Ho...Acarbose is used to control postpran-dial blood glucose in patients with type 2 diabetes and impaired glucose tolerance,since it improves insulin resistance and reduces blood lipids and cardiovascular complications.However,in recent years,many studies have found that acarbose can mediate and regulate a variety of neurotransmitter-related diseases,although the mechanisms are not clear.Therefore,this paper analyzes the clinical effect of acarbose and its mediating effect on neurotransmitters of mental disorders through insulin,braingut axis,and calorie restriction,to provide a reference for the new clinical applications of acarbose.展开更多
Objective:To determine the active components of Eupolyphaga sinensis Walker(Tu Bie Chong)and explore the mechanisms underlying its fracture-healing ability.Methods: A modified Einhorn method was used to develop a rat ...Objective:To determine the active components of Eupolyphaga sinensis Walker(Tu Bie Chong)and explore the mechanisms underlying its fracture-healing ability.Methods: A modified Einhorn method was used to develop a rat tibial fracture model.Progression of bone healing was assessed using radiological methods.Safranin O/fast green and CD31 immunohistochemical staining were performed to evaluate the growth of bone cells and angiogenesis at the fracture site.Methylthiazoletetrazolium blue and wound healing assays were used to analyze cell viability and migration.The Transwell assay was used to explore the invasion capacity of the cells.Tubule formation assays were used to assess the angiogenesis capacity of human vascular endothelial cells(HUVECs).qRT-PCR was used to evaluate the changes in gene transcription levels.Results: Tu Bie Chong fraction 3(TF3)significantly shortened the fracture healing time in model rats.X-ray results showed that on day 14,fracture healing in the TF3 treatment group was significantly better than that in the control group(P=.0086).Tissue staining showed that cartilage growth and the number of H-shaped blood vessels at the fracture site of the TF3 treatment group were better than those of the control group.In vitro,TF3 significantly promoted the proliferation and wound healing of MC3T3-E1s and HUVECs(all P<.01).Transwell assays showed that TF3 promoted the migration of HUVECs,but inhibited the migration of MC3T3-E1 cells.Tubule formation experiments confirmed that TF3 markedly promoted the ability of vascular endothelial cells to form microtubules.Gene expression analysis revealed that TF3 significantly promoted the expression of VEGFA,SPOCD1,NGF,and NGFR in HUVECs.In MC3T3-E1 cells,the transcript levels of RUNX2 and COL2A1 were significantly elevated following TF3 treatment.Conclusion: TF3 promotes fracture healing by promoting bone regeneration associated with the RUNX2 pathway and angiogenesis associated with the VEGFA pathway.展开更多
Objective:To discuss the effect of the combined therapy of levemir and acarbose on T cell subsets and function of isletβ cells in elder patients with early-onset type 2 Diabetes Mellitus. Methods:According to the num...Objective:To discuss the effect of the combined therapy of levemir and acarbose on T cell subsets and function of isletβ cells in elder patients with early-onset type 2 Diabetes Mellitus. Methods:According to the number parity of entry sequence, 100 cases of elder patients with early-onset type 2 Diabetes Mellitus are divided into the control group and the observation group of 50 cases. The control group was treated with novolin and acarbose, the observation group was given subcutaneous injection of levemir and acarbose treatment. Compare the T cell subsets and function of isletβ cells in two group of patients before the treatment (T0), treatment for 4 weeks (T1) ,treatment for 8 weeks (T2).Results:(1) The levels of T0, T1, T2CD3+, CD4+, CD4+/CD8+ were increased in both groups, and CD8+ decreased. Among them, the levels of T1, T2CD3+, CD4+, CD4+/CD8+ of the observation group were obviously higher than the control group, the level of CD8+ was lowly than the control group, the difference was statistically significant;(2) In the stage of T0, T1, T2, the levels of FPG, HbA1c, HOMA-IR were showed a downward trend, the levels of FIns, HOMA-B were increased. In these two groups, the levels of T1, T2FPG, HbA1c, HOMA-IR of the observation group were lower than the control group, and the levels of FIns, HOMA-B were higher than the control group, the difference was statistically significant;(3) In the control group occurred 3 cases of hypoglycemia, and the incidence of adverse reactions was 6%. However, in the observation group no occurred adverse reactions, the difference was statistically significant.Conclusions:The combined therapy of levemir and acarbose in elder patients with early-onset type 2 Diabetes Mellitus, It helps to improve immune function, protect the isletβ-cell function.展开更多
Acarbose is an agent that has been used to treat type 2 diabetes for about 30 years;it prevents postprandial hyperglycemia by inhibiting carbohydrate digestion in the small intestine.Since incretin-based treatments ha...Acarbose is an agent that has been used to treat type 2 diabetes for about 30 years;it prevents postprandial hyperglycemia by inhibiting carbohydrate digestion in the small intestine.Since incretin-based treatments have been preferred over the last 10 to 15 years,the use of acarbose is not as common in treating type 2 diabetes as before.Some studies have shown that acarbose also produces a weight-loss effect by increasing glucagon-like peptide 1(GLP-1).The positive effect of acarbose on GLP-1,and increasing evidence that it provides cardiovascular protection,suggests that acarbose may again be considered among the first-choice antidiabetic agents,as it was in the 1990s.展开更多
Objectives: To investigate the effects of insulin resistance on serum androgen level and ovulation of women with polycystic ovary syndrome (PCOS) and observe clinic role of acarbose in the treatment of hyperinsulinemi...Objectives: To investigate the effects of insulin resistance on serum androgen level and ovulation of women with polycystic ovary syndrome (PCOS) and observe clinic role of acarbose in the treatment of hyperinsulinemia, postprandial hyperglycemia and anovulation. Methods: 14 women accompanied by postprandial hyperglycemia with PCOS were administrated by acarbose for 12 weeks.14 age-matched individuals who had similar body mass index and normal menstruation were served as controls. Results: Serum T levels declined significantly from 4.09±1.04 nmol/L to 1.71±0.54 nmol/L (P<0.001), after acarbose treatment for 12 weeks. 12 out of 14 cases restored ovulation and menstrual cycles after acarbose treatment, among which 4 got pregnant. Conclusion: Acarbose may play a role on reducing postprandial hyperglycemia and HbAic levels, increase ISI and FSG/FI, indirectly reduce serum androgen levels through reducing plasma insulin level and recover ovarian ovulation in PCOS women with postprandial hyperglycemia.展开更多
AIM: To compare the combinative and individual effect of acarbose and gymnemic acid (GA) on maltose absorption and hydrolysis in small intestine to determine whether nutrient control in diabetic care can be improved b...AIM: To compare the combinative and individual effect of acarbose and gymnemic acid (GA) on maltose absorption and hydrolysis in small intestine to determine whether nutrient control in diabetic care can be improved by combination of them. METHODS: The absorption and hydrolysis of maltose were studied by cyclic perfusion of intestinal loops in situ and motility of the intestine was recorded with the intestinal ring in vitro using Wistar rats. RESULTS: The total inhibitory rate of maltose absorption was improved by the combination of GA (0.1g/L-1.0 g/L) and acarbose (0.1 mmol/L-2.0 mmol/L) throughout their effective duration (P 【0.05, U test of Mann-Whitney), although the improvement only could be seen at a low dosage during the first hour. With the combination, inhibitory duration of acarbose on maltose absorption was prolonged to 3h and the inhibitory effect onset of GA was fastened to 15 min. GA suppressed the intestinal mobility with a good correlation (r = 0.98) to the inhibitory effect of GA on maltose absorption and the inhibitory effect of 2 mmol/L (high dose) acarbose on maltose hydrolysis was dual modulated by 1g/L GA in vivo indicating that the combined effects involved the functional alteration of intestinal barriers. CONCLUSION: There are augmented effects of acarbose and GA,which involve pre-cellular and paracellular barriers. Diabetic care can be improved by employing the combination.展开更多
Two sets of CCD photometric observations for contact binary TU Boo were obtained in 2020 and 2021.Different from its asymmetric light curves published from the literature,our BVRcIc-band curves show that the heights o...Two sets of CCD photometric observations for contact binary TU Boo were obtained in 2020 and 2021.Different from its asymmetric light curves published from the literature,our BVRcIc-band curves show that the heights of maximum are almost equal.These distortions of light curves possibly indicate that the components were active in past 25 yr,but they were stable in the last two years.For total-eclipse binary TU Boo,due to some star-spots on the surface of the components,the physical structure obtained by many investigators are different.Therefore,the symmetric multi-color light curves in 2020,2021 are important for understanding configuration and evolution of this system.By using the Wilson–Devinney program,it is confirmed that TU Boo is an A-type shallow-contact binary with the temperature difference ofΔT=152 K and fill-out of f=14.67%.In the O−C diagram of orbital period analysis,a cyclic oscillation superimposed on a continuous decrease was determined.The long-term decreasing is often explained by the mass transfer from the more massive star to less massive one,this system will evolve into a deeper contact binary with time.The cyclic oscillations computed from much more CCD times of light minimum maybe result from the light-travel time effect via the presence of a third body.These characters of structure,evolution and ternary belong to typical A-type W UMa binaries with spectral G.展开更多
基金Supported by the National Basic Research Program of China(2011CB710800)National Special Program for Key Science and Technology of China(2008ZX09204-004)
文摘Acarbose, a potent α-glucosidase inhibitor, is widely used as an oral anti-diabetic drug for the treatment of the type 2, non-insulin-dependent diabetes. In this work, a gel type strong acid cation exchange resin 001×4 was applied to isolate acarbose from fermentation broth. It was demonstrated that cation exchanger 001×4 displayed a large adsorption capacity and quick exchange rate for acarbose. The static adsorption equilibrium data were well fitted to the Langmuir equation. Column adsorption experiments demonstrated that high dynamic adsorption capacity was reached at bed height of 104.4 mm, feed flow rate of 1.0 ml·min 1and acarbose concentration of 4.0 mg·ml 1.Under the optimized conditions, the column chromatography packed with cation exchanger 001×4 recovered 74.3%(by mass) of acarbose from Actinoplanes utahensis ZJB-08196 fermentation broth with purity of 80.1%(by mass),demonstrating great potential in the practical applications in acarbose separation.
基金financed from the grant of the National Social Science Foundation General Project(No.23BZS010)。
文摘Jiu Ai Tu(The Moxa Treatment)from the Song dynasty is the earliest surviving painting that focuses on the subject of acupuncture and moxibustion.This paper takes the medical activities depicted in the artwork as its research object and systematically analyzes the external treatment methods for abscesses during the Song dynasty reflected in Jiu Ai Tu.By examining the understanding of abscesses during that period,the paper explores the level of development in external medicine techniques.By analyzing the medical awareness and behaviors of patients when facing such severe illnesses,it aims to explore the societal cognition and experiences regarding health and disease.The paper attempts to present the folk medical ecology of the Song dynasty represented by Jiu Ai Tu.
基金This study is registered at Chinese Clinical Trial Registry Center.The registration number is ChiCTRTRC-08000231.
文摘BACKGROUND The waist-to-height ratio(WHtR)is a promising anthropometric measure used to evaluate cardiovascular risk in diabetes and metabolic syndrome patients.The metformin and acarbose in Chinese as the initial hypoglycaemic treatment trial demonstrated that acarbose and metformin reduced the WHtR after 24 wk of treatment.AIM To investigate the factors associated with a decrease in the WHtR in newly diagnosed Chinese type 2 diabetes patients receiving acarbose or metformin monotherapy.METHODS At 24 wk,343 patients in the acarbose treatment and 333 patients in the metformin treatment were included in this analysis.On the basis of the reduction in the WHtR,these participants were divided into the following two groups:LowΔWHtR group and highΔWHtR group.Metabolic and related parameters associated with a highΔWHtR were investigated using univariate and multivariate logistic regression analyses.RESULTS A significant decrease in the WHtR was observed in both treatment groups(acarbose:-0.015,95%confidence interval[CI]:-0.018 to-0.012,P<0.001;metformin:-0.013,95%CI:-0.016 to-0.010,P<0.001).In both the acarbose and metformin groups,the WHtR of the women was more likely to be reduced than that of the men.In the acarbose group,a lower baseline area under the curve of glucagon-like peptide 1(AUCGLP-1)was associated with a highΔWHtR(odds ratio[OR]=0.796,P<0.001),while a higher baseline AUCGLP-1 was associated with a highΔWHtR in the patients treated with metformin(OR=1.133,P=0.025).Regarding the changes from baseline,an increase in AUCGLP-1 was associated with a highΔWHtR in the acarbose(OR=1.121,P=0.016)but not metformin group.A higher reduction in high-density lipoprotein cholesterol/non-highdensity lipoprotein cholesterol was also associated with a highΔWHtR in the acarbose arm(OR=20.735,P=0.001).In the metformin arm,a higher reduction in fasting plasma glucose(OR=0.843,P=0.039)and total cholesterol was associated with a highΔWHtR(OR=0.743,P=0.013).CONCLUSION A lower glucagon-like peptide 1 level and higher increase in glucagon-like peptide 1 are associated with a high reduction in the WHtR in newly diagnosed Chinese diabetes patients receiving treatment with acarbose.
文摘Acarbose is used to control postpran-dial blood glucose in patients with type 2 diabetes and impaired glucose tolerance,since it improves insulin resistance and reduces blood lipids and cardiovascular complications.However,in recent years,many studies have found that acarbose can mediate and regulate a variety of neurotransmitter-related diseases,although the mechanisms are not clear.Therefore,this paper analyzes the clinical effect of acarbose and its mediating effect on neurotransmitters of mental disorders through insulin,braingut axis,and calorie restriction,to provide a reference for the new clinical applications of acarbose.
基金supported by“the Fundamental Research Funds for the Central Universities”(2020-JYB-ZDGG-054)“Beijing university of Chinese medicine XINAO Award Fund”(2019)Beijing University of Chinese Medicine Scientific Research and Development Fund(2170072220002).
文摘Objective:To determine the active components of Eupolyphaga sinensis Walker(Tu Bie Chong)and explore the mechanisms underlying its fracture-healing ability.Methods: A modified Einhorn method was used to develop a rat tibial fracture model.Progression of bone healing was assessed using radiological methods.Safranin O/fast green and CD31 immunohistochemical staining were performed to evaluate the growth of bone cells and angiogenesis at the fracture site.Methylthiazoletetrazolium blue and wound healing assays were used to analyze cell viability and migration.The Transwell assay was used to explore the invasion capacity of the cells.Tubule formation assays were used to assess the angiogenesis capacity of human vascular endothelial cells(HUVECs).qRT-PCR was used to evaluate the changes in gene transcription levels.Results: Tu Bie Chong fraction 3(TF3)significantly shortened the fracture healing time in model rats.X-ray results showed that on day 14,fracture healing in the TF3 treatment group was significantly better than that in the control group(P=.0086).Tissue staining showed that cartilage growth and the number of H-shaped blood vessels at the fracture site of the TF3 treatment group were better than those of the control group.In vitro,TF3 significantly promoted the proliferation and wound healing of MC3T3-E1s and HUVECs(all P<.01).Transwell assays showed that TF3 promoted the migration of HUVECs,but inhibited the migration of MC3T3-E1 cells.Tubule formation experiments confirmed that TF3 markedly promoted the ability of vascular endothelial cells to form microtubules.Gene expression analysis revealed that TF3 significantly promoted the expression of VEGFA,SPOCD1,NGF,and NGFR in HUVECs.In MC3T3-E1 cells,the transcript levels of RUNX2 and COL2A1 were significantly elevated following TF3 treatment.Conclusion: TF3 promotes fracture healing by promoting bone regeneration associated with the RUNX2 pathway and angiogenesis associated with the VEGFA pathway.
文摘Objective:To discuss the effect of the combined therapy of levemir and acarbose on T cell subsets and function of isletβ cells in elder patients with early-onset type 2 Diabetes Mellitus. Methods:According to the number parity of entry sequence, 100 cases of elder patients with early-onset type 2 Diabetes Mellitus are divided into the control group and the observation group of 50 cases. The control group was treated with novolin and acarbose, the observation group was given subcutaneous injection of levemir and acarbose treatment. Compare the T cell subsets and function of isletβ cells in two group of patients before the treatment (T0), treatment for 4 weeks (T1) ,treatment for 8 weeks (T2).Results:(1) The levels of T0, T1, T2CD3+, CD4+, CD4+/CD8+ were increased in both groups, and CD8+ decreased. Among them, the levels of T1, T2CD3+, CD4+, CD4+/CD8+ of the observation group were obviously higher than the control group, the level of CD8+ was lowly than the control group, the difference was statistically significant;(2) In the stage of T0, T1, T2, the levels of FPG, HbA1c, HOMA-IR were showed a downward trend, the levels of FIns, HOMA-B were increased. In these two groups, the levels of T1, T2FPG, HbA1c, HOMA-IR of the observation group were lower than the control group, and the levels of FIns, HOMA-B were higher than the control group, the difference was statistically significant;(3) In the control group occurred 3 cases of hypoglycemia, and the incidence of adverse reactions was 6%. However, in the observation group no occurred adverse reactions, the difference was statistically significant.Conclusions:The combined therapy of levemir and acarbose in elder patients with early-onset type 2 Diabetes Mellitus, It helps to improve immune function, protect the isletβ-cell function.
文摘Acarbose is an agent that has been used to treat type 2 diabetes for about 30 years;it prevents postprandial hyperglycemia by inhibiting carbohydrate digestion in the small intestine.Since incretin-based treatments have been preferred over the last 10 to 15 years,the use of acarbose is not as common in treating type 2 diabetes as before.Some studies have shown that acarbose also produces a weight-loss effect by increasing glucagon-like peptide 1(GLP-1).The positive effect of acarbose on GLP-1,and increasing evidence that it provides cardiovascular protection,suggests that acarbose may again be considered among the first-choice antidiabetic agents,as it was in the 1990s.
文摘Objectives: To investigate the effects of insulin resistance on serum androgen level and ovulation of women with polycystic ovary syndrome (PCOS) and observe clinic role of acarbose in the treatment of hyperinsulinemia, postprandial hyperglycemia and anovulation. Methods: 14 women accompanied by postprandial hyperglycemia with PCOS were administrated by acarbose for 12 weeks.14 age-matched individuals who had similar body mass index and normal menstruation were served as controls. Results: Serum T levels declined significantly from 4.09±1.04 nmol/L to 1.71±0.54 nmol/L (P<0.001), after acarbose treatment for 12 weeks. 12 out of 14 cases restored ovulation and menstrual cycles after acarbose treatment, among which 4 got pregnant. Conclusion: Acarbose may play a role on reducing postprandial hyperglycemia and HbAic levels, increase ISI and FSG/FI, indirectly reduce serum androgen levels through reducing plasma insulin level and recover ovarian ovulation in PCOS women with postprandial hyperglycemia.
基金Supported by Grant for Promotion of Science from Tottori Bioscience Foundation(1997-1998)Japan and Japanese Government(Ministry of Education,Science and Culture of Japan,MONBUSHO)scholarship No.933241(1994-1999)Japan in part.Dr.Luo was supported by the scholarships.
文摘AIM: To compare the combinative and individual effect of acarbose and gymnemic acid (GA) on maltose absorption and hydrolysis in small intestine to determine whether nutrient control in diabetic care can be improved by combination of them. METHODS: The absorption and hydrolysis of maltose were studied by cyclic perfusion of intestinal loops in situ and motility of the intestine was recorded with the intestinal ring in vitro using Wistar rats. RESULTS: The total inhibitory rate of maltose absorption was improved by the combination of GA (0.1g/L-1.0 g/L) and acarbose (0.1 mmol/L-2.0 mmol/L) throughout their effective duration (P 【0.05, U test of Mann-Whitney), although the improvement only could be seen at a low dosage during the first hour. With the combination, inhibitory duration of acarbose on maltose absorption was prolonged to 3h and the inhibitory effect onset of GA was fastened to 15 min. GA suppressed the intestinal mobility with a good correlation (r = 0.98) to the inhibitory effect of GA on maltose absorption and the inhibitory effect of 2 mmol/L (high dose) acarbose on maltose hydrolysis was dual modulated by 1g/L GA in vivo indicating that the combined effects involved the functional alteration of intestinal barriers. CONCLUSION: There are augmented effects of acarbose and GA,which involve pre-cellular and paracellular barriers. Diabetic care can be improved by employing the combination.
基金sponsored by Natural Science Foundation of Xinjiang Uygur Autonomous Region (No.2022DO1A164)the Joint Research Found (No.U1831109)in Astronomy under cooperative agreement between the National Natural Science Foundation of China (NSFC)and Chinese Academy of Sciences (CAS)the Natural Science Foundation of Shandong Province (No.ZR2020QA048)。
文摘Two sets of CCD photometric observations for contact binary TU Boo were obtained in 2020 and 2021.Different from its asymmetric light curves published from the literature,our BVRcIc-band curves show that the heights of maximum are almost equal.These distortions of light curves possibly indicate that the components were active in past 25 yr,but they were stable in the last two years.For total-eclipse binary TU Boo,due to some star-spots on the surface of the components,the physical structure obtained by many investigators are different.Therefore,the symmetric multi-color light curves in 2020,2021 are important for understanding configuration and evolution of this system.By using the Wilson–Devinney program,it is confirmed that TU Boo is an A-type shallow-contact binary with the temperature difference ofΔT=152 K and fill-out of f=14.67%.In the O−C diagram of orbital period analysis,a cyclic oscillation superimposed on a continuous decrease was determined.The long-term decreasing is often explained by the mass transfer from the more massive star to less massive one,this system will evolve into a deeper contact binary with time.The cyclic oscillations computed from much more CCD times of light minimum maybe result from the light-travel time effect via the presence of a third body.These characters of structure,evolution and ternary belong to typical A-type W UMa binaries with spectral G.
