Budd-Chiari syndrome is a congestive hepatopathy caused by blockage of hepatic veins. This syndrome occurs in 1/100 000 in the general population. Hypercoagulable state could be identified in 75% of the patients; more...Budd-Chiari syndrome is a congestive hepatopathy caused by blockage of hepatic veins. This syndrome occurs in 1/100 000 in the general population. Hypercoagulable state could be identified in 75% of the patients; more than one etiologic factor may play a role in 25% of the patients. Primary myeloproliferative diseases are the leading cause of the disease. Two of the hepatic veins must be blocked for clinically evident disease. Liver congestion and hypoxic damage of hepatocytes eventually result in predominantly centrilobular fibrosis. Doppler ultrasonography of the liver should be the initial diagnostic procedure. Hepatic venography is the reference procedure if required. Additionally liver biopsy may be helpful for differential diagnosis. The prognosis of the chronic form is acceptable compared to other chronic liver diseases.展开更多
Objective:To investigate the effect of recurrent laryngeal nerve(RLN)identification on the complications after total thyroidectomy and lobectomy.Methods:Total 134 consecutive patients undergoing total thyroidectomy or...Objective:To investigate the effect of recurrent laryngeal nerve(RLN)identification on the complications after total thyroidectomy and lobectomy.Methods:Total 134 consecutive patients undergoing total thyroidectomy or thyroid lobectomy from January 2003 to November 2004 were investigated retrospectively.Patients were divided into two groups:RLN identified (Group A)or not(Group B).The two groups were compared for RLN injury and hypocalcaemia.Results:The numbers of patients and nerves at risk were 71 and 129 in Group A,and 63 and 121 in Group B,respectively.RLN injury in Group A(0)was sig- nificantly lower than that in Group B(57.9%)patients,75.8%nerves)for the numbers of patients(P=0.016)and nerves at risk (P=0.006).Temporary hypocalcaemia was significantly higher in Group A than in Group B(1424.1%vs 610.3%,P=0.049). Permanent complications in Group B were significantly higher than those in Group A(1320.6%vs 45.6%,P=0.009).Con- clusion:RLN injury was prevented and permanent complications were decreased by identifying the whole course and branches of the recurrent laryngeal nerve during total thyroidectomy.展开更多
There is uncertain result with regard to the use of inhalation or instillation steroids to prevent bronchopulmonary dysplasia in preterm infants. This meta-analysis was designed to evaluate the efficacy and safety of ...There is uncertain result with regard to the use of inhalation or instillation steroids to prevent bronchopulmonary dysplasia in preterm infants. This meta-analysis was designed to evaluate the efficacy and safety of early airway administration (within 2 days after birth) of corticosteroids and pulmonary surfactant (PS) for preventing bronchopulmonary dysplasia (BPD) in premature infants with neonatal respiratory distress syndrome (NRDS). The related studies were retrieved in PubMed, EMBASE, the Cochrane Library, Clinical Trial, CNKI, Wanfang and VIP Database from inception to August 2018. Two reviewers independently screened the studies to ensure that all patients with diagnosis of NRDS were enrolled to studies within 1 day after birth, assessed the quality of included studies by GRADEpro system and extracted the data for review. The meta-analysis was performed by RevMan 5.2 software. A subgroup analysis about inhaled corticosteroid (ICS) delivery method was made between ICS inhalation subgroup [inhalation of ICS by nebulizer or metered dose inhaler (MDI)] and ICS intratracheal instillation subgroup (PS used as a vehicle). Eight randomized controlled trials were enrolled in the meta-analysis, 5 trials of which stated the randomized method, grouping and blinded method, and the follow-up procedures were reported. GRADEpro system showed high quality of 4 trials (5 articles), and the rest 4 trials had moderate quality. Meta-analysis showed that the incidence of BPD was decreased in ICS group, the relative risk (RR) was 0.56 (95% CI: 0.42-0.76), and similar trends were found in ICS inhalation subgroup and ICS intratracheal instillation subgroup, with the corresponding RR being 0.58 (95% CI: 0.41-0.82) and 0.47 (95% CI: 0.24-0.95) respectively. ICS could also significantly reduce the mortality risk as compared with placebo control group (RR: 0.67;95% CI: 0.45-0.99), with RR of ICS inhalation subgroup and ICS intratracheal instillation subgroup being 0.81 (95% CI: 0.34-1.94) and 0.64 (95% CI: 0.41-0.99) respectively. M展开更多
Currently,ionizing radiation(IR)plays a key role in the agricultural and medical industry,while accidental exposure resulting from leakage of radioactive sources or radiological terrorism is a serious concern.Exposure...Currently,ionizing radiation(IR)plays a key role in the agricultural and medical industry,while accidental exposure resulting from leakage of radioactive sources or radiological terrorism is a serious concern.Exposure to IR has various detrimental effects on normal tissues.Although an increased risk of carcinogenesis is the best-known long-term consequence of IR,evidence has shown that other diseases,particularly diseases related to inflammation,are common disorders among irradiated people.Autoimmune disorders are among the various types of immune diseases that have been investigated among exposed people.Thyroid diseases and diabetes are two autoimmune diseases potentially induced by IR.However,the precise mechanisms of IR-induced thyroid diseases and diabetes remain to be elucidated,and several studies have shown that chronic increased levels of inflammatory cytokines after exposure play a pivotal role.Thus,cytokines,including interleukin-1(IL-1),tumor necrosis factor(TNF-α)and interferon gamma(IFN-α),play a key role in chronic oxidative damage following exposure to IR.Additionally,these cytokines change the secretion of insulin and thyroid-stimulating hormone(TSH).It is likely that the management of inflammation and oxidative damage is one of the best strategies for the amelioration of these diseases after a radiological or nuclear disaster.In the present study,we reviewed the evidence of radiation-induced diabetes and thyroid diseases,as well as the potential roles of inflammatory responses.In addition,we proposed that the mitigation of inflammatory and oxidative damage markers after exposure to IR may reduce the incidence of these diseases among individuals exposed to radiation.展开更多
The major drawback associated with PEEK implants is their biologically inert surface,which caused unsatisfactory cellular response and poor adhesion between the implants and surrounding soft tissues against proper bon...The major drawback associated with PEEK implants is their biologically inert surface,which caused unsatisfactory cellular response and poor adhesion between the implants and surrounding soft tissues against proper bone growth.In this study,polyetheretherketone(PEEK)was incorporated with calcium hydroxyapatite(cHAp)to fabricate a PEEK-cHAp biocomposite,using the fused deposition modeling(FDM)method and a surface treatment strategy to create microporous architectures onto the filaments of PEEK lattice scaffold.Also,nanostructure and morphological tests of the PEEK-cHAp biocomposite were modeled and analyzed on the FDM-printed PEEK-cHAp biocomposite sample to evaluate its mechanical and thermal strengths as well as in vitro cytotoxicity via a scanning electron microscope(SEM).A technique was used innovatively to create and investigate the porous nanostructure of the PEEK with controlled pore size and distribution to promote cell penetration and biological integration of the PEEK-cHAp into the tissue.In vivo tests demonstrated that the surface-treated micropores facilitated the adhesion of newly regenerated soft tissues to form tight implant-tissue interfacial bonding between the cHAp and PEEK.The results of the cell culture depicted that PEEK-cHAp exhibited better cell proliferation attachment spreading and higher alkaline phosphatase activity than PEEK alone.Apatite islands formed on the PEEK-cHAp composite after immersion in simulated body fluid of Dulbecco’s modified Eagle medium(DMEM)for 14 days and grew continuously with more or extended periods.The microstructure treatment of the crystallinity of PEEK was comparatively and significantly different from the PEEK-cHAp sample,indicating a better treatment of PEEK-cHAp.The in vitro results obtained from the PEEK-cHAp biocomposite material showed its biodegradability and performance suitability for bone implants.This study has potential applications in the field of biomedical engineering to strengthen the conceptual knowledge of FDM and medical implants fabricated展开更多
Human driven vehicles(HDVs)with selfish objectives cause low traffic efficiency in an un-signalized intersection.On the other hand,autonomous vehicles can overcome this inefficiency through perfect coordination.In thi...Human driven vehicles(HDVs)with selfish objectives cause low traffic efficiency in an un-signalized intersection.On the other hand,autonomous vehicles can overcome this inefficiency through perfect coordination.In this paper,we propose an intermediate solution,where we use vehicular communication and a small number of autonomous vehicles to improve the transportation system efficiency in such intersections.In our solution,two connected autonomous vehicles(CAVs)lead multiple HDVs in a double-lane intersection in order to avoid congestion in front of the intersection.The CAVs are able to communicate and coordinate their behavior,which is controlled by a deep reinforcement learning(DRL)agent.We design an altruistic reward function which enables CAVs to adjust their velocities flexibly in order to avoid queuing in front of the intersection.The proximal policy optimization(PPO)algorithm is applied to train the policy and the generalized advantage estimation(GAE)is used to estimate state values.Training results show that two CAVs are able to achieve significantly better traffic efficiency compared to similar scenarios without and with one altruistic autonomous vehicle.展开更多
In this study, we present systematic petrological, geochemical, LA-ICP-MS zircon U-Pb ages and Nd isotopic data for the A-type granites and syenites from Suizhou-Zaoyang region. The results show that the peralkaline A...In this study, we present systematic petrological, geochemical, LA-ICP-MS zircon U-Pb ages and Nd isotopic data for the A-type granites and syenites from Suizhou-Zaoyang region. The results show that the peralkaline A-type granites and syenites were episodically emplaced in Suizhou-Zaoyang region between 450±3 and 441±7 Ma which corresponds to Late Ordovician and Early Silurian periods, respectively. Petrologically, the syenite-peralkaline granite association comprises of nephefine normative-syenite and alkaline granite in Guanzishan and quartz normative syenite and alkafine granite in Huangyangshan. The syenite-granite associations are ferroan to alkali in composition. They depict characteristics of typical OIB （oceanic island basalts） derived A-type granites in multi-elements primitive normalized diagram and Ybffa vs. Y/Nb as well as Ce/Nb vs. Y/Nb binary plots. Significant depletion in Ba, Sr, P, Ti and Eu indicates fractionation of feldspars, biotite, amphiboles and Ti-rich augite. The values of eNd（t） in Guanzishan nepheline syenite and alkaline granite are ＋1.81 and ＋2.26, respectively and the calculated two-stage model age for these rocks are 1 040 and 1 003 Ma, respectively. On the other hand, the Huangyangshan alkaline granite has eNd（t） values ranging from ＋2.61 to ＋3.46 and a relatively younger two-stage Nd model age values ranging from 906 to 975 Ma, respectively. Based on these data, we inferred that the Guanzishan nepheline syenites and granites were formed from fractional crystallization of OIB-like basic magmas derived from upweliing of metasomatized lithospheric mantle. The Huangyangshan quartz syenite and granite on the other hand, were formed from similar magmas through fractional crystallization with low input from the ancient crustal rocks. Typically, the rocks exhibit Al-type granite affinity and classified as within plate granites associated with the Ordovician crustal extension and the Silurian rifting.展开更多
During the 2022 growing season (August to November) at the Federal University of Technology, Minna School farm, Niger State, an experiment was conducted to investigate the influence of mulching on Okras growth, yield,...During the 2022 growing season (August to November) at the Federal University of Technology, Minna School farm, Niger State, an experiment was conducted to investigate the influence of mulching on Okras growth, yield, and moisture content was examined across four distinct growth stages (initial, development, mid, and late) and at varying soil depths (0 - 30 cm and 30 - 60 cm). The study employed a randomised complete block design with four replications, encompassing control (T0), groundnut shells mulch (T1), black polythene mulch (T2), and white polythene mulch (T3) as treatments. The highest average Okra fresh pod yield, amounting to 23.4 t/ha, was achieved by implementing white plastic mulch, contrasting with the control treatment, which yielded the lowest at 22 t/ha. Notably, the control plots exhibited yield reductions of up to 32% compared to the plots employing white plastic mulching. The utilisation of mulch had a notable impact on the overall crop yield, with the superior quality evident in the treatment employing white plastic mulch (26 t/ha). The control treatment exhibited the lowest quality at 24.3 t/ha. Groundnut shell mulch influenced moisture conservation, but no significant variance was observed compared to the control plots. Therefore, the study suggests that polythene mulch may be the most suitable type to enhance the quality of okra production by conserving soil moisture. Among the biodegradable and non-biodegradable mulches used in this study, white polythene mulch was the most effective.展开更多
Inorganic scale deposits are a major water-related problem encountered in producing oil and gas wells. The harshness of scale deposits is dependent on the field operating conditions. Scale deposits can vary from mild ...Inorganic scale deposits are a major water-related problem encountered in producing oil and gas wells. The harshness of scale deposits is dependent on the field operating conditions. Scale deposits can vary from mild scaling tendencies to extreme. In general, the scale deposit will cause a reduction in formation pores, declining productivity and eventually blockage of the wellbore and hence unexpected downtime if it is allowed to persevere. To overcome this, the productivity of an oil and gas well is ensured by handling scale deposits via removal or prevention methods. Scale prevention is the best and cost-e ective method for handling scale deposits that ensures production continuity. Inhibition through 'threshold' scale inhibitor treatment is the most common method that is proven to prevent or reduce likely deposits. This paper examines the art of synthetic scale inhibitors, in particular, threshold scale inhibitors in oil and gas production. It discusses the chemistry of those inhibitors, inhibition mechanisms, treatment methods and key properties for their applications. It also highlights the chemistry of the synthetic routes often used to produce them in the laboratory and/or industry. Finally, it highlights the environmental concerns for the applicability of threshold scale inhibitors.展开更多
Some physical and chemical properties, mineral content and fatty acid compositions of kernel and oils of several walnut types (Büyük Oba, Kaman2, Kaman5) were determined. The oil yields from these kernels ch...Some physical and chemical properties, mineral content and fatty acid compositions of kernel and oils of several walnut types (Büyük Oba, Kaman2, Kaman5) were determined. The oil yields from these kernels changed between 61.4% to 72.8%. The crude fibre contents of ker nels ranged between 3.77% and 3.80%. In add ition, crude protein contents of kernels ranged between 7.05% and 8.10%. While the peroxide values of kernel oils change between 3.18 meq/ Kg and 3.53 meq/Kg, acidity values ranged be tween 0.35% and 0.56%. The main fatty acids of walnut kernel oils were oleic, linoleic, linolenic and palmitic acids. Linoleic acid contents of ker nel oils varied between 49.7% and 55.5%. On the other hand, oleic acid contents ranged between 20.5% and 26.4%. As a result, the present study showed the walnut kernels of the researched species of walnut kernels from Turkey are a potential source of valuable oil which might be used for edible and other industrial applica tions.展开更多
Background: The choice of the appropriate operative intervention in patients with late and neglected hip fracture continuous to be a huge dilemma for orthopedic surgeons. Purpose: To evaluate the satisfaction or other...Background: The choice of the appropriate operative intervention in patients with late and neglected hip fracture continuous to be a huge dilemma for orthopedic surgeons. Purpose: To evaluate the satisfaction or otherwise of some treatment options using the modified Harris-hip score (HHS) in resource poor setting. Materials and Methods: A retrospective cross-sectional study conducted at ATBUTH, Bauchi. Data of 60 patients over the age of 18 years with hip fractures (femoral neck, intertrochanteric and sub trochanteric fractures) who had operative intervention between 1st September 2019 and 31st August 2020 with cannulated screws, Proximal femur lock compression plate (PFLCP), cementlessor cemented bipolar hemiarthroplasty (BHA). Results: The mean age of studied patients was 65.7 ± 16.1 years, with age ranging from 19 - 101 years. M:F ratio was 1.2:1 across all age groups and 1:1.4 amongst those >60 years. 51 patients (85%) presented > 1 week after injury with 24 patients (40%) sustaining hip fractures from low energy trivial indoor fall and 28 patients (46.7%) mostly younger sustaining fractures from high energy motor vehicular accident (MVA). The prevalence rate for femoral neck, intertrochanteric and subtrochanteric fractures were 32 (53.3%), 17 (28.3%) and 11 (18.3%) respectively. From the data retrieved, 21patients (35.0%), 17 patients (28.3%), 20 patients (33.3%) and 2 patients (3.3%) had PFLCP, cemented BHA, cementless BHA and cannulated screw fixation respectively. Most (66.7%) of those who had PFLCP achieved satisfactory radiologic union and there was also 94.1% and 85% satisfactory outcome rate amongst the patients with cemented BHA and cementless BHA respectively. Irrespective of the operative intervention method at 1 year follow-up, there was a statistically significant improvement in post-operative HHS (P value 0.02), with 83.4% having good to excellent results. Conclusion: There is highrate of late and neglected hip fracture in our environment. Satisfactory outcome with statistically significant imp展开更多
满天星是当今世界最流行的鲜切花配花之一,茎腐病是满天星的一种常见病害,严重时导致植株枯萎死亡,影响鲜花的观赏性和利用价值,造成一定的经济损失。2021年3月,笔者在云南省昆明市海口镇发现满天星茎腐病,该病主要为害茎基部,表现为茎...满天星是当今世界最流行的鲜切花配花之一,茎腐病是满天星的一种常见病害,严重时导致植株枯萎死亡,影响鲜花的观赏性和利用价值,造成一定的经济损失。2021年3月,笔者在云南省昆明市海口镇发现满天星茎腐病,该病主要为害茎基部,表现为茎基部腐烂和萎蔫。为明确其病原,本研究对满天星茎腐病病原菌进行分离与鉴定。柯赫氏法则证明该分离物可造成满天星组培苗和盆栽苗表现出与田间病株相似的症状,经接种后获得的分离物与田间自然发病的分离物一致。通过形态学鉴定,分离物能产生大量致密的气生菌丝,颜色从白色到淡橙色或黄色不等,菌落背面有暗红色色素沉积。显微镜观察发现其分离物的分生孢子呈镰刀形,腹面较平直,背侧呈拱形,具有3~6个隔膜,分生孢子大小为(21.1~57.9)μm×(2.7~5.1)μm(n=100),未见小型分生孢子,形态学上与镰刀菌属病原真菌相似。通过对其ITS基因序列与形态学鉴定,将分离物初步确定为禾谷镰孢复合种(Fusarium graminearum species complex,FGSC),为进一步确定亚种,使用翻译延伸因子(TEF-1α)序列进行测序,发现该分离物与南方镰孢菌(F.meridionale)的同源性达100%。因此结合形态学和分子生物学特征,满天星茎腐病的病原确定为南方镰孢菌。目前国内尚未发现由南方镰孢菌侵染为害满天星茎部的相关研究报道,本研究结果将为防治满天星病害提供重要理论依据。展开更多
基金Yusuf Bayraktar, MD, Gastroenterology Department, Hacettepe University School of Medicine, Ankara, Turkey. bayrak@hacettepe.edu.trTelephone: +90-312-3051712 Fax: +90-312-3051490
文摘Budd-Chiari syndrome is a congestive hepatopathy caused by blockage of hepatic veins. This syndrome occurs in 1/100 000 in the general population. Hypercoagulable state could be identified in 75% of the patients; more than one etiologic factor may play a role in 25% of the patients. Primary myeloproliferative diseases are the leading cause of the disease. Two of the hepatic veins must be blocked for clinically evident disease. Liver congestion and hypoxic damage of hepatocytes eventually result in predominantly centrilobular fibrosis. Doppler ultrasonography of the liver should be the initial diagnostic procedure. Hepatic venography is the reference procedure if required. Additionally liver biopsy may be helpful for differential diagnosis. The prognosis of the chronic form is acceptable compared to other chronic liver diseases.
文摘Objective:To investigate the effect of recurrent laryngeal nerve(RLN)identification on the complications after total thyroidectomy and lobectomy.Methods:Total 134 consecutive patients undergoing total thyroidectomy or thyroid lobectomy from January 2003 to November 2004 were investigated retrospectively.Patients were divided into two groups:RLN identified (Group A)or not(Group B).The two groups were compared for RLN injury and hypocalcaemia.Results:The numbers of patients and nerves at risk were 71 and 129 in Group A,and 63 and 121 in Group B,respectively.RLN injury in Group A(0)was sig- nificantly lower than that in Group B(57.9%)patients,75.8%nerves)for the numbers of patients(P=0.016)and nerves at risk (P=0.006).Temporary hypocalcaemia was significantly higher in Group A than in Group B(1424.1%vs 610.3%,P=0.049). Permanent complications in Group B were significantly higher than those in Group A(1320.6%vs 45.6%,P=0.009).Con- clusion:RLN injury was prevented and permanent complications were decreased by identifying the whole course and branches of the recurrent laryngeal nerve during total thyroidectomy.
文摘There is uncertain result with regard to the use of inhalation or instillation steroids to prevent bronchopulmonary dysplasia in preterm infants. This meta-analysis was designed to evaluate the efficacy and safety of early airway administration (within 2 days after birth) of corticosteroids and pulmonary surfactant (PS) for preventing bronchopulmonary dysplasia (BPD) in premature infants with neonatal respiratory distress syndrome (NRDS). The related studies were retrieved in PubMed, EMBASE, the Cochrane Library, Clinical Trial, CNKI, Wanfang and VIP Database from inception to August 2018. Two reviewers independently screened the studies to ensure that all patients with diagnosis of NRDS were enrolled to studies within 1 day after birth, assessed the quality of included studies by GRADEpro system and extracted the data for review. The meta-analysis was performed by RevMan 5.2 software. A subgroup analysis about inhaled corticosteroid (ICS) delivery method was made between ICS inhalation subgroup [inhalation of ICS by nebulizer or metered dose inhaler (MDI)] and ICS intratracheal instillation subgroup (PS used as a vehicle). Eight randomized controlled trials were enrolled in the meta-analysis, 5 trials of which stated the randomized method, grouping and blinded method, and the follow-up procedures were reported. GRADEpro system showed high quality of 4 trials (5 articles), and the rest 4 trials had moderate quality. Meta-analysis showed that the incidence of BPD was decreased in ICS group, the relative risk (RR) was 0.56 (95% CI: 0.42-0.76), and similar trends were found in ICS inhalation subgroup and ICS intratracheal instillation subgroup, with the corresponding RR being 0.58 (95% CI: 0.41-0.82) and 0.47 (95% CI: 0.24-0.95) respectively. ICS could also significantly reduce the mortality risk as compared with placebo control group (RR: 0.67;95% CI: 0.45-0.99), with RR of ICS inhalation subgroup and ICS intratracheal instillation subgroup being 0.81 (95% CI: 0.34-1.94) and 0.64 (95% CI: 0.41-0.99) respectively. M
文摘Currently,ionizing radiation(IR)plays a key role in the agricultural and medical industry,while accidental exposure resulting from leakage of radioactive sources or radiological terrorism is a serious concern.Exposure to IR has various detrimental effects on normal tissues.Although an increased risk of carcinogenesis is the best-known long-term consequence of IR,evidence has shown that other diseases,particularly diseases related to inflammation,are common disorders among irradiated people.Autoimmune disorders are among the various types of immune diseases that have been investigated among exposed people.Thyroid diseases and diabetes are two autoimmune diseases potentially induced by IR.However,the precise mechanisms of IR-induced thyroid diseases and diabetes remain to be elucidated,and several studies have shown that chronic increased levels of inflammatory cytokines after exposure play a pivotal role.Thus,cytokines,including interleukin-1(IL-1),tumor necrosis factor(TNF-α)and interferon gamma(IFN-α),play a key role in chronic oxidative damage following exposure to IR.Additionally,these cytokines change the secretion of insulin and thyroid-stimulating hormone(TSH).It is likely that the management of inflammation and oxidative damage is one of the best strategies for the amelioration of these diseases after a radiological or nuclear disaster.In the present study,we reviewed the evidence of radiation-induced diabetes and thyroid diseases,as well as the potential roles of inflammatory responses.In addition,we proposed that the mitigation of inflammatory and oxidative damage markers after exposure to IR may reduce the incidence of these diseases among individuals exposed to radiation.
基金We appreciate the funding/financial support received from the Higher Education Innovation Fund(HEIF)of De Montfort University,Leicester,UK,under Research Project No.0043.06.
文摘The major drawback associated with PEEK implants is their biologically inert surface,which caused unsatisfactory cellular response and poor adhesion between the implants and surrounding soft tissues against proper bone growth.In this study,polyetheretherketone(PEEK)was incorporated with calcium hydroxyapatite(cHAp)to fabricate a PEEK-cHAp biocomposite,using the fused deposition modeling(FDM)method and a surface treatment strategy to create microporous architectures onto the filaments of PEEK lattice scaffold.Also,nanostructure and morphological tests of the PEEK-cHAp biocomposite were modeled and analyzed on the FDM-printed PEEK-cHAp biocomposite sample to evaluate its mechanical and thermal strengths as well as in vitro cytotoxicity via a scanning electron microscope(SEM).A technique was used innovatively to create and investigate the porous nanostructure of the PEEK with controlled pore size and distribution to promote cell penetration and biological integration of the PEEK-cHAp into the tissue.In vivo tests demonstrated that the surface-treated micropores facilitated the adhesion of newly regenerated soft tissues to form tight implant-tissue interfacial bonding between the cHAp and PEEK.The results of the cell culture depicted that PEEK-cHAp exhibited better cell proliferation attachment spreading and higher alkaline phosphatase activity than PEEK alone.Apatite islands formed on the PEEK-cHAp composite after immersion in simulated body fluid of Dulbecco’s modified Eagle medium(DMEM)for 14 days and grew continuously with more or extended periods.The microstructure treatment of the crystallinity of PEEK was comparatively and significantly different from the PEEK-cHAp sample,indicating a better treatment of PEEK-cHAp.The in vitro results obtained from the PEEK-cHAp biocomposite material showed its biodegradability and performance suitability for bone implants.This study has potential applications in the field of biomedical engineering to strengthen the conceptual knowledge of FDM and medical implants fabricated
文摘Human driven vehicles(HDVs)with selfish objectives cause low traffic efficiency in an un-signalized intersection.On the other hand,autonomous vehicles can overcome this inefficiency through perfect coordination.In this paper,we propose an intermediate solution,where we use vehicular communication and a small number of autonomous vehicles to improve the transportation system efficiency in such intersections.In our solution,two connected autonomous vehicles(CAVs)lead multiple HDVs in a double-lane intersection in order to avoid congestion in front of the intersection.The CAVs are able to communicate and coordinate their behavior,which is controlled by a deep reinforcement learning(DRL)agent.We design an altruistic reward function which enables CAVs to adjust their velocities flexibly in order to avoid queuing in front of the intersection.The proximal policy optimization(PPO)algorithm is applied to train the policy and the generalized advantage estimation(GAE)is used to estimate state values.Training results show that two CAVs are able to achieve significantly better traffic efficiency compared to similar scenarios without and with one altruistic autonomous vehicle.
基金the support from the National Natural Science Foundation of China(No.41502046)partial financial support by the China Geological Survey(No.DD20160030the Fundamental Research Funds for the Central Universities,China University of Geosciences,Wuhan(No.CUGCJ1711)
文摘In this study, we present systematic petrological, geochemical, LA-ICP-MS zircon U-Pb ages and Nd isotopic data for the A-type granites and syenites from Suizhou-Zaoyang region. The results show that the peralkaline A-type granites and syenites were episodically emplaced in Suizhou-Zaoyang region between 450±3 and 441±7 Ma which corresponds to Late Ordovician and Early Silurian periods, respectively. Petrologically, the syenite-peralkaline granite association comprises of nephefine normative-syenite and alkaline granite in Guanzishan and quartz normative syenite and alkafine granite in Huangyangshan. The syenite-granite associations are ferroan to alkali in composition. They depict characteristics of typical OIB （oceanic island basalts） derived A-type granites in multi-elements primitive normalized diagram and Ybffa vs. Y/Nb as well as Ce/Nb vs. Y/Nb binary plots. Significant depletion in Ba, Sr, P, Ti and Eu indicates fractionation of feldspars, biotite, amphiboles and Ti-rich augite. The values of eNd（t） in Guanzishan nepheline syenite and alkaline granite are ＋1.81 and ＋2.26, respectively and the calculated two-stage model age for these rocks are 1 040 and 1 003 Ma, respectively. On the other hand, the Huangyangshan alkaline granite has eNd（t） values ranging from ＋2.61 to ＋3.46 and a relatively younger two-stage Nd model age values ranging from 906 to 975 Ma, respectively. Based on these data, we inferred that the Guanzishan nepheline syenites and granites were formed from fractional crystallization of OIB-like basic magmas derived from upweliing of metasomatized lithospheric mantle. The Huangyangshan quartz syenite and granite on the other hand, were formed from similar magmas through fractional crystallization with low input from the ancient crustal rocks. Typically, the rocks exhibit Al-type granite affinity and classified as within plate granites associated with the Ordovician crustal extension and the Silurian rifting.
文摘During the 2022 growing season (August to November) at the Federal University of Technology, Minna School farm, Niger State, an experiment was conducted to investigate the influence of mulching on Okras growth, yield, and moisture content was examined across four distinct growth stages (initial, development, mid, and late) and at varying soil depths (0 - 30 cm and 30 - 60 cm). The study employed a randomised complete block design with four replications, encompassing control (T0), groundnut shells mulch (T1), black polythene mulch (T2), and white polythene mulch (T3) as treatments. The highest average Okra fresh pod yield, amounting to 23.4 t/ha, was achieved by implementing white plastic mulch, contrasting with the control treatment, which yielded the lowest at 22 t/ha. Notably, the control plots exhibited yield reductions of up to 32% compared to the plots employing white plastic mulching. The utilisation of mulch had a notable impact on the overall crop yield, with the superior quality evident in the treatment employing white plastic mulch (26 t/ha). The control treatment exhibited the lowest quality at 24.3 t/ha. Groundnut shell mulch influenced moisture conservation, but no significant variance was observed compared to the control plots. Therefore, the study suggests that polythene mulch may be the most suitable type to enhance the quality of okra production by conserving soil moisture. Among the biodegradable and non-biodegradable mulches used in this study, white polythene mulch was the most effective.
文摘Inorganic scale deposits are a major water-related problem encountered in producing oil and gas wells. The harshness of scale deposits is dependent on the field operating conditions. Scale deposits can vary from mild scaling tendencies to extreme. In general, the scale deposit will cause a reduction in formation pores, declining productivity and eventually blockage of the wellbore and hence unexpected downtime if it is allowed to persevere. To overcome this, the productivity of an oil and gas well is ensured by handling scale deposits via removal or prevention methods. Scale prevention is the best and cost-e ective method for handling scale deposits that ensures production continuity. Inhibition through 'threshold' scale inhibitor treatment is the most common method that is proven to prevent or reduce likely deposits. This paper examines the art of synthetic scale inhibitors, in particular, threshold scale inhibitors in oil and gas production. It discusses the chemistry of those inhibitors, inhibition mechanisms, treatment methods and key properties for their applications. It also highlights the chemistry of the synthetic routes often used to produce them in the laboratory and/or industry. Finally, it highlights the environmental concerns for the applicability of threshold scale inhibitors.
基金This work was supported by Selçuk University Scientific Research Project(S.U.-BAP.Konya-Turkey).
文摘Some physical and chemical properties, mineral content and fatty acid compositions of kernel and oils of several walnut types (Büyük Oba, Kaman2, Kaman5) were determined. The oil yields from these kernels changed between 61.4% to 72.8%. The crude fibre contents of ker nels ranged between 3.77% and 3.80%. In add ition, crude protein contents of kernels ranged between 7.05% and 8.10%. While the peroxide values of kernel oils change between 3.18 meq/ Kg and 3.53 meq/Kg, acidity values ranged be tween 0.35% and 0.56%. The main fatty acids of walnut kernel oils were oleic, linoleic, linolenic and palmitic acids. Linoleic acid contents of ker nel oils varied between 49.7% and 55.5%. On the other hand, oleic acid contents ranged between 20.5% and 26.4%. As a result, the present study showed the walnut kernels of the researched species of walnut kernels from Turkey are a potential source of valuable oil which might be used for edible and other industrial applica tions.
文摘Background: The choice of the appropriate operative intervention in patients with late and neglected hip fracture continuous to be a huge dilemma for orthopedic surgeons. Purpose: To evaluate the satisfaction or otherwise of some treatment options using the modified Harris-hip score (HHS) in resource poor setting. Materials and Methods: A retrospective cross-sectional study conducted at ATBUTH, Bauchi. Data of 60 patients over the age of 18 years with hip fractures (femoral neck, intertrochanteric and sub trochanteric fractures) who had operative intervention between 1st September 2019 and 31st August 2020 with cannulated screws, Proximal femur lock compression plate (PFLCP), cementlessor cemented bipolar hemiarthroplasty (BHA). Results: The mean age of studied patients was 65.7 ± 16.1 years, with age ranging from 19 - 101 years. M:F ratio was 1.2:1 across all age groups and 1:1.4 amongst those >60 years. 51 patients (85%) presented > 1 week after injury with 24 patients (40%) sustaining hip fractures from low energy trivial indoor fall and 28 patients (46.7%) mostly younger sustaining fractures from high energy motor vehicular accident (MVA). The prevalence rate for femoral neck, intertrochanteric and subtrochanteric fractures were 32 (53.3%), 17 (28.3%) and 11 (18.3%) respectively. From the data retrieved, 21patients (35.0%), 17 patients (28.3%), 20 patients (33.3%) and 2 patients (3.3%) had PFLCP, cemented BHA, cementless BHA and cannulated screw fixation respectively. Most (66.7%) of those who had PFLCP achieved satisfactory radiologic union and there was also 94.1% and 85% satisfactory outcome rate amongst the patients with cemented BHA and cementless BHA respectively. Irrespective of the operative intervention method at 1 year follow-up, there was a statistically significant improvement in post-operative HHS (P value 0.02), with 83.4% having good to excellent results. Conclusion: There is highrate of late and neglected hip fracture in our environment. Satisfactory outcome with statistically significant imp
文摘满天星是当今世界最流行的鲜切花配花之一,茎腐病是满天星的一种常见病害,严重时导致植株枯萎死亡,影响鲜花的观赏性和利用价值,造成一定的经济损失。2021年3月,笔者在云南省昆明市海口镇发现满天星茎腐病,该病主要为害茎基部,表现为茎基部腐烂和萎蔫。为明确其病原,本研究对满天星茎腐病病原菌进行分离与鉴定。柯赫氏法则证明该分离物可造成满天星组培苗和盆栽苗表现出与田间病株相似的症状,经接种后获得的分离物与田间自然发病的分离物一致。通过形态学鉴定,分离物能产生大量致密的气生菌丝,颜色从白色到淡橙色或黄色不等,菌落背面有暗红色色素沉积。显微镜观察发现其分离物的分生孢子呈镰刀形,腹面较平直,背侧呈拱形,具有3~6个隔膜,分生孢子大小为(21.1~57.9)μm×(2.7~5.1)μm(n=100),未见小型分生孢子,形态学上与镰刀菌属病原真菌相似。通过对其ITS基因序列与形态学鉴定,将分离物初步确定为禾谷镰孢复合种(Fusarium graminearum species complex,FGSC),为进一步确定亚种,使用翻译延伸因子(TEF-1α)序列进行测序,发现该分离物与南方镰孢菌(F.meridionale)的同源性达100%。因此结合形态学和分子生物学特征,满天星茎腐病的病原确定为南方镰孢菌。目前国内尚未发现由南方镰孢菌侵染为害满天星茎部的相关研究报道,本研究结果将为防治满天星病害提供重要理论依据。
