Paclitaxel for second-line treatment of squamous cell carcinoma of the head and neck:A multicenter retrospective Italian study

BACKGROUND Squamous cell carcinoma of the head and neck(SCCHN)accounts for 3%of all malignant tumors in Italy.Immune checkpoint inhibitors combined with chemotherapy is first-line treatment for SCCHN;however,second-line treatment options are limited.Taxanes are widely used for combination therapy of SCCHN,as clinical trials have shown their efficacy in patients with this disease,partic ularly in patients with prior therapy.AIM To perform a multicenter retrospective study on the efficacy and safety of weekly paclitaxel for SCCHN.METHODS All patients were previously treated with at least one systemic therapy regimen,which included platinum-based therapy in the vast majority.No patient received prior immunotherapy.RESULTS Median progression-free survival(mPFS)was 3.4 months and median overall survival(mOS)was 6.5 months.Subgroup analysis was performed according to three principal prognostic factors:Smoking,alcohol consumption,and body mass index.Analysis demonstrated reduced survival,both mOS and mPFS,in the unfavorable prognostic groups,with the biggest deltas observed in mOS.CONCLUSION Weekly paclitaxel provided favorable survival and disease control rates,with low severe adverse events.Paclitaxel is a safe and valid therapeutic option for patients with SCCHN who received prior therapy.

Dissimilar survival and clinicopathological characteristics of mucinous adenocarcinoma located in pancreatic head and body/tail

BACKGROUND Growing evidence shows that pancreatic tumors in different anatomical locations have different characteristics,which have a significant impact on prognosis.However,no study has reported the differences between pancreatic mucinous adenocarcinoma(PMAC)in the head vs the body/tail of the pancreas.AIM To investigate the differences in survival and clinicopathological characteristics between PMAC in the head and body/tail of pancreas.METHODS A total of 2058 PMAC patients from the Surveillance,Epidemiology,and End Results database diagnosed between 1992 and 2017 were retrospectively reviewed.We divided the patients who met the inclusion criteria into pancreatic head group(PHG)and pancreatic body/tail group(PBTG).The relationship between two groups and risk of invasive factors was identified using logistic regression analysis.Kaplan-Meier analysis and Cox regression analysis were conducted to compare the overall survival(OS)and cancer-specific survival(CSS)of two patient groups.RESULTS In total,271 PMAC patients were included in the study.The 1-year,3-year,and 5-year OS rates of these patients were 51.6%,23.5%,and 13.6%,respectively.The 1-year,3-year,and 5-year CSS rates were 53.2%,26.2%,and 17.4%,respectively.The median OS of PHG patients was longer than that of PBTG patients(18 vs 7.5 mo,P<0.001).Compared to PHG patients,PBTG patients had a greater risk of metastases[odds ratio(OR)=2.747,95%confidence interval(CI):1.628-4.636,P<0.001]and higher staging(OR=3.204,95%CI:1.895-5.415,P<0.001).Survival analysis revealed that age<65 years,male sex,low grade(G1-G2),low stage,systemic therapy,and PMAC located at the pancreatic head led to longer OS and CSS(all P<0.05).The location of PMAC was an independent prognostic factor for CSS[hazard ratio(HR)=0.7,95%CI:0.52-0.94,P=0.017].Further analysis demonstrated that OS and CSS of PHG were significantly better than PBTG in advanced stage(stage III-IV).CONCLUSION Compared to the pancreatic body/tail,PMAC located in the pancreatic head has better survival and favorable clinicopathological characteristics.

Theoretical Analysis and Experimental Verification on Valve-less Piezoelectric Pump with Hemisphere-segment Bluff-body

Existing researches on no-moving part valves in valve-less piezoelectric pumps mainly concentrate on pipeline valves and chamber bottom valves, which leads to the complex structure and manufacturing process of pump channel and chamber bottom. Furthermore, position fixed valves with respect to the inlet and outlet also makes the adjustability and controllability of flow rate worse. In order to overcome these shortcomings, this paper puts forward a novel implantable structure of valve-less piezoelectric pump with hemisphere-segments in the pump chamber. Based on the theory of flow around bluff-body, the flow resistance on the spherical and round surface of hemisphere-segment is different when fluid flows through, and the macroscopic flow resistance differences thus formed are also different. A novel valve-less piezoelectric pump with hemisphere-segment bluff-body （HSBB） is presented and designed. HSBB is the no-moving part valve. By the method of volume and momentum comparison, the stress on the bluff-body in the pump chamber is analyzed. The essential reason of unidirectional fluid pumping is expounded, and the flow rate formula is obtained. To verify the theory, a prototype is produced. By using the prototype, experimental research on the relationship between flow rate, pressure difference, voltage, and frequency has been carried out, which proves the correctness of the above theory. This prototype has six hemisphere-segments in the chamber filled with water, and the effective diameter of the piezoelectric bimorph is 30mm. The experiment result shows that the flow rate can reach 0.50 mL/s at the frequency of 6 Hz and the voltage of 110 V. Besides, the pressure difference can reach 26.2 mm H20 at the frequency of 6 Hz and the voltage of 160 V. This research proposes a valve-less piezoelectric pump with hemisphere-segment bluff-body, and its validity and feasibility is verified through theoretical analysis and experiment.

Flow patterns and boundary conditions for inlet and outlet conduits of large pump system with low head

The flow patterns in the inlet and outlet conduits have a decisive effect on the safe, stable, and highly efficient operation of the pump in a large pumping station with low head. The numerical simulation of three-dimensional （3D） turbulence flow in conduits is an important method to study the hydraulic performance and conduct an optimum hydraulic design for the conduits. With the analyses of the flow patterns in the inlet and outlet conduits, the boundary conditions of the numerical simulation for them can be determined. The main obtained conclusions are as follows： （i） Under normal operation conditions, there is essentially no pre-swirl flow at the impeller chamber inlet of an axial-flow pump system, based on which the boundary condition at the inlet conduit may be defined. （ii） The circulation at the guide vane outlet of an axial-flow pump system has a great effect on the hydraulic performance of the outlet conduit, and there is optimum circulation for the performance. Therefore, it is strongly suggested to design the guide vane according to the optimum circulation. （iii） The residual circulation at the guide vane outlet needs to be considered for the inlet boundary condition of the outlet conduit, and the value of the circulation may be measured in a specially designed test model.

Cross influence of discharge and circulation on head loss of conduit of pump system with low head

The relationship between the head loss and the discharge and circulation of the conduit of a pump system with low head is an important problem with an obvious influence on the improvement of its hydraulic performance. The velocity circulation from the pump guide vane makes the relationship more complicated, which has to be understood comprehensively. The results indicate that, under the condition of zero circulation, the head loss of the inlet and outlet conduits is in proportion to the square of discharge. Under the condition that the Reynolds number is satisfied with the resistant square area, the conduit loss is in proportion to the square of discharge for the similar working points with different speeds in a certain rotational speed range, indicating that the pump system efficiency is constant. The outlet conduit loss of design discharge for a pump system with low head depends on the velocity circulation from the guide vane exit, and the relationship between the loss and the circulation is an open curve with an upward direction, meaning that there is an optimal circulation for the loss. Under the condition of various working points for a pump system with low head, the head loss of the outlet conduit is under the cross influence of both the discharge and the circulation. As a result, the relationship between the head loss and the discharge is almost linear, and the mechanism needs to be further studied.

Modeling of the Groundwater Flow and Saltwater Intrusion in the Coastal Aquifer of Fum Al Wad, Province of Laayoun, Morocco

Saltwater intrusion caused by groundwater over-exploitation from coastal aquifers poses a severe problem in many regions. The Fum Al Wad aquifer is located between Atlantic Ocean in the West and Laayoun in the East. This aquifer covers an area of 250 Km2, and represents an essential water resource for Laayoun city and the periphery regions. It is heavily exploited for water supply, agriculture and industry. The freshwater-saltwater interface is affected by groundwater extraction by public supplies, irrigation wells, and domestic wells in the coastal of this aquifer. The position of the interface is controlled by several factors: these include precipitation, recharge rate, dryness, evapotranspiration, hydraulic conductivity and hydraulic head. Landward migration of the interface freshwater-saltwater often results in a significant decrease in the water resources available for coastal communities. The volume pumped by public for irrigation and the domestic usage in 2010-2011 is estimated 2.5 Mm3/year, and in 2015 about 2.91 Mm3/year only for domestic usages. The objectives of this work are to model the groundwater flow and saltwater intrusion in the coastal aquifer of Fum Al Wad, by SEAWAT-2000 program which coupled both the version of MODFLOW-2000 and MT3DMS. They are designed to simulate variable-density groundwater flow and solute transport in three dimensions. The model is calibrated for hydraulic conductivity, specific yield, porosity, and recharge rate as well as dispersivity coefficient. The result of simulation of the hydrodynamic model during the period of 1986-2015 has revealed a piezometric drawdown with 2.3 m approximately at the level of the pumping zone. Furthermore, this piezometric depression is caused by excessive pumping of the various uses of water and its corresponding that has resulted in the migration of the saltwater intrusion into freshwater with 4.3 km approximately. The simulations result for scenarios 2020 and 2030 of Fum Al Wad aquifer showed a vertical decrease of the piezometric head (about 2.5 m) in 2030, but the saltwater intrusion has advanced diagonally to reach 4.7 km under the freshwater of groundwater of this aquifer.

A Value Engineering Analysis of Head Loss in Pumping Mains

With net zero carbon emissions targets approaching over the next 20 to 30 years, the water industry must act now to develop energy efficient techniques and designs to reduce emissions and reduce the carbon footprint of water utility providers. There is also the potential for significant energy and therefore financial savings to be realised from the adoption of more energy efficient designs approaches. Water utility providers account for a significant proportion of national electricity consumption. The purpose of this research is to determine if, over the long term, opting for a larger diameter pipe at design stage can lead to significant financial and emissions savings for water utility providers when considering pumping mains. Pumping mains are widely used throughout the water and wastewater industry where a gravity solution is not possible. 72 hypothetical water main design scenarios were analysed and the long term financial and environmental impact of each hypothetical water main was assessed. It was found across all design scenarios that larger diameter water mains were capable of delivering the same rate of flow of smaller diameter pipes at a much reduced velocity and requiring reduced pumping power. It was concluded that pumped mains of larger diameters can ultimately be more energy efficient and cost effective over the long term when selected in favour of smaller diameter pumped mains in otherwise identical design scenarios.

Effect of insulin pump and continuous intravenous insulin on ketone body metabolism, blood gas indexes and stress state in patients with diabetic ketoacidosis

Objective:To study the effect of insulin pump and continuous intravenous insulin on ketone body metabolism, blood gas indexes and stress state in patients with diabetic ketoacidosis. Methods:Patients with diabetic ketoacidosis who were treated in Meizhou Maternal and Child Heath Hospital between May 2014 and March 2017 were selected as the research subjects and randomly divided into the group A who received subcutaneous insulin infusion by insulin pump and the group B who received intravenous small-dose insulin injection by micropump. The indexes of ketone body, blood gas and stress were measured before and after treatment. Results: 12 h and 24 h after treatment, serumβ-hydroxybutyrate, MDA, NE, ACTH and Cor contents of both groups of patients were significantly lower than those before treatment while pH, HCO3- and base excess levels as well as serum SOD, GSH-Px, CAT and TAC contents were significantly higher than those before treatment, and serumβ-hydroxybutyrate, MDA, NE, ACTH and Cor contents of group A were significantly lower than those of group B while pH, HCO3- and base excess levels as well as serum SOD, GSH-Px, CAT and TAC contents were significantly higher than those of group B.Conclusion:Subcutaneous insulin infusion by insulin pump can improve ketone body metabolism, acidosis status and stress state in patients with diabetic ketoacidosis.

Flow excitation mechanisms of unbalanced impeller forces after pump power-trip of ultra-high head pump-turbines

To elucidate the dynamic mechanisms of unbalanced impellers in ultra-high head pump-turbines(PTs),this study employed a one-and three-dimensional coupled method to simulate the pump power-trip(PPT)process of an ultra-high head PT.The investigation revealed two novel pulsation frequency components,denoted as fDVand fINFT,associated with impeller forces.The pulsation intensities of these components were markedly higher than those of rotor-stator interaction frequency components in ultra-high head PTs.Notably,the fDVcomponents exhibited pulsations at 1–2 times the rated rotation frequency of the impeller,spanning the entire transition period.Meanwhile,the fINFTcomponents constituted a complex frequency band with various frequency values,primarily occurring near conditions(Q=0,n=0,M=0,and d M/dt=0).These two pulsation frequency components were predominantly linked to the unsteady evolution of dean vortices inside the volute and complex transitions of the flow pattern within the impeller,respectively.It is crucial to note that these unbalanced flow-induced impeller axial forces can elevate the risk of accidents where the rotor is subjected to significant upwind axial forces.These findings offer valuable insights into mitigating the risk of rotor lifting due to axial forces during PT events in ultra-high head PTs.

Postoperative secondary aggravation of obstructive sleep apneahypopnea syndrome and hypoxemia with bilateral carotid body tumor:A case report

BACKGROUND Carotid body tumor(CBT)is a chemoreceptor tumor located in the carotid body,accounting for approximately 0.22%of head and neck tumors.Surgery is the main treatment method for the disease.CASE SUMMARY We reviewed the diagnosis and treatment of one patient who had postoperative secondary aggravation of obstructive sleep apnea–hypopnea syndrome(OSAHS)and hypoxia after surgical resection of bilateral CBTs.This patient was admitted,and relevant laboratory and imaging examinations,and polysomnography(PSG)were performed.After the definitive diagnosis,continuous positive airway pressure(CPAP)treatment was given,which achieved good efficacy.CONCLUSION This case suggested that aggravation of OSAHS and hypoxemia is possibly caused by the postoperative complications after bilateral CBTs,and diagnosis by PSG and CPAP treatment are helpful for this patient.

Head and Neck Cancer Early Identification of Malnutrition High Risk Patients and Quality of Life Optimization

Malnutrition in Head and neck cancer (HNC) patients can be present at the moment of diagnosis. The nutritional status is determinant for the treatment success and quality of life of the patients. The nutritional status gradually declines during treatment and the majority of patients undergoing treatment will need nutritional therapy. On the other hand, HNC, like other cancers, can induce a paraneoplastic syndrome that leads to cachexia. This cachexia status is most of the times the cause of death or the cause of treatment failure. So, early identification of malnutrition high risk patients is crucial to start an adequate nutrition support intervention in HNC patients. This study aims to identify HNC patients who present malnutrition or higher risk of malnutrition;to signalize variables that support early identification of high-risk patients of becoming malnourished and to establish a dynamic relationship between malnutrition risk in these patients and Quality of Life (QoL) impacts. For six months consecutive outpatients with HNC admitted at the Head & Neck Unity of Oncology Portuguese Institute—Porto were asked to participate in the research (n = 114). The European Organisation for Research and Treatment of Cancer (EORTC) cancer-specific HRQoL questionnaire-QLQ-C30 and Malnutrition Universal Screening Tool, MUST were used. At the moment of first presentation, 32 patients (28.1%) presented high-risk of malnutrition. HNC patients with oral cavity and oropharynx tumour locations, older, with low literacy or with BMI under 18.5 at the moment of diagnosis, represent a high-risk group. When HNC is considered, a dynamic and bi-directional connection between malnutrition and QoL is observed. A significant (p Emotional and social functional scales and all symptom scales—including pain, presented significant differences between high and medium risk of malnutrition patients. Fatigue, pain, insomnia, appetite loss and financial difficulties were domains directly related to high risk of malnutrition patients. Pain scores were significantly higher (43.23) in the high-risk patients when compared to medium risk patients (11.67). Nutrition support should be considered at any stage of the pathway —especially in high risk group—in order to optimize tumour treatment results, reduction of adverse effects of therapy and improving both QoL and survival.

Study on regurgitation of a bearing-less mini axial aortic valvo-pump with closed impeller

The back-flow of an aortic valvo-pump will re-duce the pumping flow rate but can wash out the gap between the rotor and the stator, and thus can improve the antithrombogenicity of the de-vice. To investigate the regurgitation of a 23mm OD aortic valvo-pump, its closed impeller was replaced by a cylinder and hereby the valvo- pump had lost its pumping function. The pres-sure head crossing the aortic valvo-pump was maintained by a locally made pulsatile centrifugal pump, beating rhythmically from 30 to 120mmHg. The back flow from outlet to inlet of valvo-pump via the above-mentioned gap was measured. Results demonstrated that this gap and the pressure head had remarkable effect on back- flow;a larger gap and/or a larger pressure head would lead to a larger back-flow. By 0,20mm gap and 100mmHg pressure head, the valvo-pump had ca. 0,8 l/min back-flow. Instantaneous meas-urement indicated that the back-flow had a pul-satile form with high rate during diastole while low rate during systole of the natural heart imi-tated by pulsatile centrifugal pump. The pump rotated at 12500rpm, 15000rpm and 17500rpm respectively, but it was found the rotating speed had no affection on back-flow. This investigation provides a basis for pump design seeking for both increase of the flow rate and improvement of the compatibility;the former is particularly important for a mini axial pump and the latter is extremely difficult for closed impeller.

当归不同药用部位的化学成分及药理作用研究进展

当归作为“分根梢”理论的代表药材,其以不同药用部位分别入药起源于唐代,形成于金元,兴盛于明清;经历代医家临床实践总结,逐渐确立了归头止血、归身补血、归尾活血的作用功效。现代研究表明,当归中含有当归多糖、挥发油、有机酸、无机盐等药效部位及阿魏酸、绿原酸、欧前胡素、藁本内酯等药效成分;在当归头、当归身及当归尾等不同药用部位中,上述药效物质基础的种类分布均匀、区别不大,但含量及相关比例差异明显;多数学者认为,含量、比例差异可能是导致当归不同药用部位存在较大药理作用差异的主要原因。通过对相关文献的检索,梳理和总结近年来国内外对当归不同药用部位中药效物质基础分布情况及相关药理作用的研究,从当归不同药用部位中药效物质基础的种类分布和含量差异两个方面综合分析,并结合相关药效物质基础对应的药理作用研究,找寻当归不同药用部位间存在的“成分-效用”关系,以期为历代医家将当归按当归头、当归身、当归尾分别入药提供更强有力的佐证,同时为当归提出进一步研究的主要方向和思路。

农田灌溉光伏水泵系统性能测试分析

【目的】探究农田灌溉光伏水泵系统综合用能需求特性,提高该系统性能可靠性和实用性。【方法】基于高效水泵和研发的逆变器,构建了农田灌溉光伏水泵系统,结合系统装置构成与运行特点,对不同扬程运行工况下的电性能参数和扬水效率特性及水泵流量与功率特性等进行测试分析。【结果】在一定太阳辐射强度范围内,调速运行的水泵流量与输出频率有较好一致性;稳定运行时段的水泵流量可达到2 m^(3)·h^(-1);定扬程24.8 m下,系统最大扬水效率达12.7%,日平均扬水效率11.6%,日扬水量13.1 m^(3);当扬程降低到14.0 m时,最大扬水效率和日平均效率分别比前者低3.2%和3.6%,表明减低扬程并不一定能提高系统扬水效率,但对输出流量有影响。【结论】该农田灌溉光伏水泵系统配置稳态和动态性能良好,扬水能力可满足省水微灌和植被绿化等基本农业生产需要。

不同干燥方式对灵芝子实体干燥品质的影响

采用热风干燥、热泵干燥、微波热泵耦合干燥、热泵梯度升温干燥、热泵梯度降温干燥等干燥方式,探究不同干燥方式对灵芝子实体感官、营养及理化品质的影响。结果表明,微波12 min+60℃热泵干燥脱水效率最高,较单一热风干燥至少缩短180 min;微波4 min+60℃热泵干燥色泽保持相对较好;微波12 min+60℃热泵干燥粗多糖含量最高,较60℃热风干燥提高了63.26%;热泵梯度降温干燥对DPPH自由基的清除能力最强;60℃热泵干燥水溶性指数最高。从提高生产效率和营养成分保留率角度考虑,优先选择微波12 min+60℃热泵干燥方式;从产品良好色泽角度考虑,优先选择微波4 min+60℃热泵干燥方式;从产品良好功能活性角度考虑,优先选择热泵梯度降温干燥、60℃热泵干燥方式,为灵芝子实体干燥方式的选择提供理论依据。

侧通道泵结构设计方法初探

文章结合工程实际需要,对比分析了侧通道泵的结构型式和工作原理,在此基础上建立了部分流式切线离心泵扬程系数与侧通道泵扬程系数的关系;根据离心泵的设计流程和设计方法,以计算案例的形式给出了侧通道泵几何结构参数设计方法,依据此设计方法获得的几何参数,绘制了单级侧通道泵结构图。几何结构参数设计是现代泵设计的第一步,文章设计方法的初步形成,为侧通道泵产品的设计、进一步的结构优化、性能提升奠定了基础。

高速离心泵启动过程的仿真与优化

为研究离心泵启动过程中泵内的流场和外特性变化,首先使用CFD软件提供的二次开发接口,通过编写cel函数来精准加载流量和转速变化规律,从而模拟启动整个变化过程。数值模拟结果表明:在启动初期扬程和效率均会出现脉冲现象,针对此脉冲现象进行改善,对离心泵的结构参数进行改变,如叶片包角、出口宽度等,并且将不同结构参数的仿真结果构建成神经网络,使用遗传算法找出最优解,以实现泵初期扬程、效率脉冲的减小。发现扬程脉冲减小3.21 m,效率脉冲降低2.87%。

酶标仪法测定离心泵泵头表面肝素涂层生物活性的研究

目的 建立酶标仪法测定离心泵泵头表面肝素的生物活性。方法 由抗凝血酶(AT)饱和的肝素化表面失活的凝血酶量来量化肝素生物活性:肝素表面与过量的血浆蛋白AT结合,形成AT饱和的肝素化表面(过量的AT通过清洗程序去除),上述肝素化表面又与过量凝血酶Ⅱa结合,残留的凝血酶Ⅱa与显色底物反应,凝血酶肽键H-D-Phe-Pip-Arg-pNa被裂解,释放出生色团,其可以在405 nm下进行测试并定量。结果 应用酶标仪上波长405 nm时的动力学吸光度评估生物活性,生物活性测定表明:对照品(无涂层的离心泵泵头)的结果为-0.01 IU/cm^(2)(≤0.05 IU/cm^(2)),所有3种供试品的结果为0.29 IU/cm^(2)、0.40 IU/cm^(2)和0.32 IU/cm^(2)(均≥0.1 IU/cm^(2)),符合生物活性试验的有效性标准,对照品和供试品的生物活性均被视为通过。结论 通过酶标仪定量测试凝血酶肽键裂解释放生色团的含量,可得到与肝素涂层反应的Ⅱa的量,进一步反推AT的量,最终计算出肝素涂层的生物活性。该方法操作简便,一次可以测定多份样本,检测速度快;具有需要的样本量少、重复性好的特点,适用于对离心泵泵头表面肝素涂层的生物活性定量检测。

抽水蓄能电站单机容量与机组转速选择

通过分析国内外已建抽水蓄能电站机组主要技术参数,研究抽蓄电站定转速混流式水泵水轮机水头与单机容量、参数水平的关系,提出了不同水头段抽水蓄能电站单机容量和比速系数选择原则,推荐了合适的机组额定转速范围,可提高抽水蓄能电站水泵水轮机选型设计的工作效率和成果质量。