Production quality and pricing strategy for substitutable products under comparison effects

Comparison effects have been studied extensively in many fields.In particular,existing operations management articles have discussed the impact of comparison effects on enterprises'production and pricing decisions.Research has also shown that consumers'purchasing decisions are primarily determined by three factors:product quality,selling price,and comparison effects.The current study introduces the concepts of social and temporal comparison effects to examine how comparison effects influence a monopolist's production quality and pricing strategy for substitutable products.Results reveal the following:(1)Setting different prices for even two types of substitutable products with negligible quality differences can divide customers into three groups under the influence of social comparison effects in a single-stage model.(2)The monopolist should avoid using a price discrimination strategy in which products with a short market life cycle have the same quality but different prices.(3)When the market life cycle of products is sufficiently long in the single-product market and the market with two substitutable products,the monopolist's optimal choice in the second stage is to keep production quality constant and increase the selling price.Consequently,the number of buyers does not decrease because of temporal comparison effects.Therefore,the firm increases its revenue.(4)For the market with two substitutable products with quality differences,one approximate optimal strategy for the enterprise in the second stage is to keep the selling price constant with the assumption that product quality cannot be adjusted after the first period.At this point,the consumption situation in the market is the same as that in the first stage.Therefore,when no external constraints exist,the monopolist firm can obtain more benefits in the second stage than in the first stage by exploiting the temporal comparison effects of consumers in the second stage.(5)When consumer identity information can be confirmed in the market,social comparison effects,similar to temporal comparison effects,could help the enterprise increase its price and profit while maintaining product quality.These social and temporal comparison effects constrain consumers.Thus,the number of people who continueto buyproducts does not decrease.

Comparison of Hypolipidemic Effect of Refined Konjac Meal With Several Common Dietary Fibers and Their Mechanisms of Action

The effects of RKM in comparison with pectin, algin and agar on lipid levels in serum and liver and on liver histopathology in rats were studied. In addition, the effects of all the tested materials on the composition and output of fecal bile acid were observed. All four kinds of dietary fiber were given at a level of 5% of diet to young male rats of Wistar strain fed on a lipid-rich diet contalning 5 % lard, 1% cholesteral and 0. 25 % cholate. All the dietary fibers tested have similar effects on serum lipid composition. In all groups, these substances prevent ed increases in total cholesterol in fasting serum, but the level of triglyceride was tmchangd.The concentrations of totaI cholesterol and triglyceride in the liver were lower in the RKM group than in the control group and the other three groups. Hepatic histopathological exami nation also showed the most significant lipotropic effect in the RKM group. The daily output of fecal bile acids (CDCA+GDCA) was significantly increased in the four experimental groups than in the normal group and the control group. The increase of CDCA was more significant than GDCA, suggesting that the increase of fecal bile acids, especially CDCA, may be one of the mechanisms by which RKM and the other three dietary fibers exerts a hypocholesterolemic effect

COMPARISON OF ASSISTANT EFFECTS AMONG ASSISTANT MOLECULES ON T CELL ACTIVATION BY SUPERANTIGEN TSST-1

对抗ＣＤ２８抗体、佛波酯（ＰＭＡ）和ＩＬ－２三种辅助分子在体外缺乏抗原提呈细胞（ＡＰＣ）的情况下辅助超抗原活化Ｔ细胞的作用进行比较。结果发现：抗ＣＤ２８抗体、ＰＭＡ和ＩＬ－２辅助超抗原活化Ｔ细胞的最适浓度分别为１０μｇ／ｍｌ、１０ｎｇ／ｍｌ和１０００ｕ／ｍｌ；其中，抗ＣＤ２８抗体辅助超抗原活化Ｔ细胞的作用最强，ＰＭＡ次之，ＩＬ－２最弱。另外，对三种辅助分子辅助超抗原活化Ｔ细胞的机制进行了探讨。本研究为今后选择合适的辅助分子与合成肽技术共同组建一种有效的探找超抗原Ｔ细胞表位的方法奠定了基础。

COMPARISON OF THE EFFECTIVENESS BETWEEN ANTERIOR CAPSULOTOMY WITH Nd:YAG LASER AND WITH BENT NEEDLE IN PATIENTS WITH CONGENITAL CATARACT

The effectiveness of capsulotomy with Nd:YAG laser and with bent needle were compared in 50 patients(66 eyes) with congenital cataract. There were 24 patients(32 eyes) in the laser group and 26 patients(34 eyes) in the needle group. There were not significant differences in sex, age, pre-operative visual acuity and intraocular pressures, and classification of cataract between the two groups. The results show that patients in the laser group have better post-operative visual acuity. The reason is YAG las...

Comparison of the Thermomagnetic and Thermal Effects duringNanocrystallization of Amorphous Fe_(76.5-x)Cu_1Nb_xSi_(13.5)B_9 Alloys

The results of thermomagnetic (TM) and calorimetric (DSC) measurements have been compared in order to clarify some details of the mechanism of nanophase-formation from Finemet-type precursors with different Nb contents. It was found that the main features of the DSC thermograms (shape, relative separation and amplitude of the exothermic peaks characteristic for the precipitation of the Fe-(Si) solid solution and the transition metal borides) depend mainly on the composition of the precursor glass, and are only slightly affected by the heating rate between 20 and 80 K/min. The amplitude of the uprise of the magnetization in the TM curves (attributed to the precipitation of bcc-Fe(Si) and borides) decreases with increasing Nb-content. The Curietemperature of the precursor glasses. Tc(am1), the remainder amorphous phases, Tc(am2) and the bcc nanophase, Tc(n-Fe) are determined from the thermomagnetic curves. The shape of the TM curves is interpreted on the basis of the reactions describing the crystalIization of the hypo-eutectic Fe-B glasses.

Comparison of the effects of autotransfusion and homologous transfusion on milieu interieur and secretion of erythropoietin

Objective To compare the effects of autotransfusion and homologous transfusion on milieu interieur and secretion of erythropoietin (EPO). Methods Thirty patients aged 8-21 yr, undergoing surgical correction of kyphoscoliosis were randomly divided into two groups of fifteen:group A and group B. In group A patients received homologous transfusion during operation, while in group B shed blood was collected from operative field and after filtration RBCs were separated by a differential centrifugation and washed in normal saline and reinfused. Anesthesia was induced with fentanyl 2 μg· kg-1 ,propofol 1 mg·kg-1 and vecuronium 0.1 mg·kg-1 and maintained with inhalation of isoflurane and 50 % N2O in oxygen and intermittent iv boluses of vecuronium and fentanyl. Blood routine, blood gases, electrolytes, plasma osmotic pressure and activated clotting time (ACT) were measured before operation, 2 h after skin incision and at the end of surgery. Blood EPO concentration was measured before operation,at the end

A comparison of the short-term effects of fixed platform versus rotating high-fiexion prosthesis for the patients with osteoarthrities of knee

Objective To compare the preliminary clinical outcome between fixed platform and rotating high-flexion prosthesis following total knee replacement(TKR).Methods Form January 2007 to December 2009,68 patients with osteoarthritis of

小麦干旱监测技术研究进展与展望

发展小麦干旱监测技术是客观监测小麦干旱程度、准确反映干旱波及范围和持续时间的基础,从而能够对小麦干旱灾害做出预警并有效地评估其影响。本文系统梳理了国内外小麦干旱监测方法,包括基于地面常规观测、基于水分控制试验、基于作物模型模拟和基于遥感手段的4个方面的研究进展。分析表明,基于地面常规观测资料构建的小麦干旱监测指数,更多地考虑到业务和服务的应用需求,具有计算过程简单、资料获取方便、物理意义明确的特点;但其以气象观测要素为主,监测结果与农业旱情存在一定的偏差。基于人工水分控制试验的监测手段,直接与小麦生长状态联系,能反映实际的旱情;但仅靠部分站点的试验监测结果难以反映大范围的小麦干旱状况。作物模型可细致描述作物生长发育的全过程以及作物生长同降水量和土壤水分之间的动态关系;但其监测所需参数较多,模型本地化释用程度不高。遥感技术能够及时、客观地获取大范围地表综合信息,但受到天气状况、地表粗糙度、地形和植被等因素的影响,反演结果具有一定的偏差。因此,对于小麦干旱监测应该针对特定地区和特定生长阶段赋予不同干旱监测指数影响权重,应用综合监测指数以更准确地反映作物干旱状况。

Comparison of Water and Soil Conservation Effect of Trees,Shrubs and Grasses in the Red Soil Area of Southern China

Assessing the effects of vegetation on water and soil conversation is the key basis for research and management of ecological restoration on water-eroded areas.In this study,the runoff depth,soil loss and corresponding precipitation of five plots planted respectively with Pueraria lobata,Lespedeza bicolor Turcz,Manglietia yuyuanensis Law,Paspalum natatu Fliigge,Paspalum wettsteinii Hackel and one control plot were observed monthly from 2003 to 2010 in Hetian Town of Changting County,Fujian Province,a typical water-eroded area in southern China.Then the effects of different vegetation on water/soil conversation(RE/SE)were determined using the ratios of runoff depth/soil loss between vegetated plots to the control plot.Meanwhile,the effect of precipitation on the water and soil loss was also analyzed.The results showed that,both the water and soil conservation effects of Pueraria lobata and Manglietia yuyuanensis Law are better than Lespedeza bicolor Turcz and Paspalum natatu,while Paspalum wettsteinii Hackel are the worst.The differences of effects of water conservation are more significantly than those of soil conversation between five kinds of vegetations.The runoff depth is mainly affected by precipitation,the determination coefficients(R2)of linear regression models between precipitation and runoff depth of all planted plots are all greater than 0.9,whereas the determination coefficients of the linear regression models between precipitation and soil loss vary form 0.3 to 0.8 for different vegetated plots.These results provide a reference for vegetation reconstruction in the current and similar areas.

核酸共提取试剂盒应用于柑橘危险性病害检测的效率评价

柑橘易受到不同遗传类型病原的复合感染,传统病原检测方法需单一核酸提取,使得检测步骤繁琐,影响检测效率。以普通单一核酸提取试剂盒为对照,采用核酸共提取试剂盒,通过分析核酸完整性和浓度以及病原检测效率,以期探讨核酸共提取试剂盒应用于柑橘危险性病害检测的可行性,从而简化柑橘病原检测方法的核酸提取步骤。结果表明,相比普通RNA提取试剂盒,核酸共提取试剂盒提取RNA的完整性、纯度、浓度以及柑橘衰退病毒病原检测效率均无显著差异,可达到相同检测效果。相比普通DNA提取试剂盒,核酸共提取试剂盒提取DNA的完整性、纯度均无显著性差异,但其浓度显著降低,使得柑橘黄龙病和柑橘溃疡病病原检测效率也显著降低;通过增加PCR反应的起始模板量,核酸共提取试剂盒检测柑橘黄龙病和柑橘溃疡病病原的效率与普通DNA试剂盒无显著差异,可达到相同检测效果。综上所述,核酸共提取试剂盒可应用于柑橘危险性病害检测,将有助于提高病原复合感染样品的检测效率。

2种木霉菌制剂对烤烟生长的影响

[目的]积极响应洱海保护行动,减轻长期大量使用化学农药带来的一系列问题。[方法]采用生物农药(木霉菌制剂),在大理市湾桥镇以K326为供试材料,采用灌根施用方法,探究东方农韵木霉菌(T_(1))、优沃美哈茨木霉菌(T_(2))、清水处理(CK)对烤烟移栽成活率、不同时期的农艺性状、生物学产量、经济性状烤后烟叶化学成分、黑胫病防控效果的影响。[结果]各处理的移栽成活率均为100%,但烟苗长势表现为T_(1)>T_(2)>CK,以T_(1)处理的烟苗茎高最高,达18.6 cm;与CK相比,2种木霉菌制剂处理在烤烟不同生长时期,对烤烟农艺性状都有不同程度的促生效果。团颗期T_(1)、T_(2)处理烟株株高、最大叶面积分别较CK增加8.53%、37.41%和2.38%、14.73%;旺长期T_(1)、T_(2)处理烟株茎围和最大叶面积分别较CK增加8.68%、30.78%和0.68%、23.99%;采烤期T_(1)、T_(2)处理最大叶面积显著提高,分别比CK增加33.36%、13.95%;在等量施肥条件下,烤后烟叶的经济性状、生物产量均随木霉菌制剂的使用而增加,T_(1)、T_(2)处理烟叶总重分别为256.4和229.0 g,比CK分别高55.4和28.0 g;T_(1)、T_(2)处理可分别增产534.58、207.30 kg/hm^(2),其产值分别增加8102.15和3621.34元/hm^(2);T_(1)、T_(2)处理烤烟中部烟叶总糖和还原糖含量较高,氯离子含量和糖碱比较低,烟草的化学成分更趋协调;与CK相比,施用木霉菌制剂均能降低黑胫病的发病率和病情指数,T_(1)和T_(2)处理对发病率和病情指数的降低效果明显,T_(1)、T_(2)处理的发病率和病情指数分别达到4.00%、1.85和3.33%、1.93,防治效果分别达53.27%和51.40%。[结论]施用木霉菌制剂对烤烟的生长发育有一定促进作用,可以防治黑胫病,减少黑胫病发生,并提高烤烟的质量和烟叶的口感。

六种布鲁菌病疫苗对绵羊与山羊免疫效果的比较

为了比较不同布鲁菌病疫苗对乌拉特草原以放牧为主的山羊与绵羊的免疫效果,我们在乌拉特草原6个苏木/镇,随机选取80~100日龄并经过布鲁菌病检测阴性的乌拉特土种绵羊羔385只、二狼山绒山羊羔275只,用6种布鲁菌病疫苗进行免疫效果比对试验。采用琥红平板凝集试验(RBPT)和试管凝集试验(SAT)分别对试验组羊接种疫苗后7、14、21、35、60、120、150、180、210、240、270 d进行转阳率和抗体效价检测;免疫后270 d进行攻毒试验。RBPT和SAT结果显示,M5-90Δ26和S2接种绵羊与山羊后抗体产生快,持续时间长;免疫后攻毒试验结果显示,A19点眼绵羊和A19-ΔVirB12株皮下注射绵羊保护比例均为4/6;M5-90Δ26绵羊皮下注射和ReV.1山羊点眼的保护比例均为4/5;本试验为乌拉特草原建立牛羊免疫无布鲁菌病区筛选理想疫苗,以及为创建全国首个牛羊免疫无布鲁菌病区制定合理的免疫程序提供了科学依据,同时对布鲁菌病疫苗的研制及国内其他地区布鲁菌病防治具有参考价值和指导作用。

同辈比较效应问卷的编制及其对抑郁、焦虑的预测研究

目的:编制青年人同辈比较效应问卷(peer comparative effects questionnaire),并考察该问卷对抑郁焦虑的预测作用。方法:应用方便取样法选取330名青年进行问卷初测,对收集的数据进行项目、探索性因子分析,筛选问卷题目,进一步完善问卷。再次应用方便取样法选取350名青年完成经筛选完善后生成的问卷,对收集的数据进行信、效度检验及验证性因素分析;测试后1个月,从350名青年中随机抽取30名进行重测来检验问卷信度。结果:(1)探索性因素分析显示问卷可保留26个题目,可分为自我激励、自我认同、自我怀疑3个维度,总解释率为53.39%。验证性因素分析显示3因素模型拟合度良好。问卷具有良好的信效度(α=0.81~0.91),可以作为相关研究的评估工具。各维度与相似测量问卷之间相容效度良好(r=0.51~0.76,均P<0.01)。(2)青年人同辈比较效应问卷的自我激励维度可显著负向预测抑郁(β=-0.16,P<0.01);自我怀疑维度能够显著正向预测抑郁(β=0.54,P<0.001)、焦虑(β=0.51,P<0.001)。结论:新编制青年人同辈比较效应问卷能够评估人际比较后产生的自我激励、自我认同和自我怀疑,且具有良好信效度。其中的自我怀疑维度可以有效预测抑郁和焦虑,自我激励维度可以有效预测抑郁。

新型空心管屏障隔振效果对比数值研究

为研究新型空心管屏障在工程隔振中的应用价值及对其影响因素进行分析,基于Plaxis3D有限元分析软件,依照已有的模型和现场试验参数建立有限元模型,并采用经过验证的有限元模型进行仿真计算。基于有限元数值分析方法,开展新型空心管隔振效果与已有模型和现场试验中屏障的对比研究;分析单根空心管高度和空心管数量对新型空心管隔振效果的影响。研究发现:新型空心管屏障平均减振系数比填充沟、排桩和波阻板小得多,彼此之间平均减振系数偏差最大可达373%,而与空沟的平均减振系数偏差较小。这一结果表明:新型空心管的隔振效果明显要优于填充沟、排桩和波阻板,而与空沟的隔振效果相接近。此外,还发现在不同的工程条件下,新型空心管隔振屏障的平均减振系数大都在0.3以下,具有很好的隔振效果;且随着空心管数量的增加,空心管的隔振效果也随之提升;在空心管总高度不变的条件下,调节单根空心管的高度对屏障的隔振效果影响很小。

社会比较倾向对高校基层管理人员转岗意愿的影响研究

教师强烈的转岗意愿是影响教育高质量发展的因素之一,探究高校基层管理人员转岗意愿的影响因素有助于稳定高校管理人员队伍。文本以我国东部、中部和西部共20个省市及自治区的高校基层管理人员为调查对象,综合运用描述性统计分析、差异性检验和结构方程模型等方法,探索社会比较倾向对高校基层管理人员转岗意愿的影响及职业倦怠的中介效应。研究结果表明,高校基层管理人员的社会比较倾向、职业倦怠和转岗意愿得分均较高;社会比较倾向与职业倦怠、转岗意愿显著正相关、职业倦怠能显著预测高校基层管理人员的转岗意愿,并在社会比较倾向对转岗意愿的影响中起到部分中介作用。基于此,保障经济诱因和非经济诱因,有效弱化高校基层管理人员的社会比较倾向;提高组织协作的能率和效率,有力缓解高校基层管理人员的职业倦怠。

桥接组合式内固定和锁定加压钢板治疗股骨干粉碎性骨折的疗效比较

目的 比较桥接组合式内固定系统和锁定加压钢板治疗股骨干粉碎性骨折的疗效。方法 2017年1月~2021年6月收治的股骨干粉碎性骨折病人97例,其中42例实施锁定加压钢板内固定手术(钢板组),55例实施桥接组合式内固定手术(桥接组),随访至少12个月。比较两组的围手术期资料、随访资料和并发症情况。结果 钢板组和桥接组的手术时间分别为(95.37±19.31)分钟和(77.83±15.32)分钟,术中出血分别为(425.37±47.56)ml和(398.72±43.29)ml,术后引流量分别为(123.42±19.87)ml和(106.39±14.20)ml,住院时间分别为(19.31±4.26)天和(16.2 4±3.79)天,两组比较差异有统计学意义(P<0.05);术后随访1年,桥接组和钢板组的髋关节ROM分别为(132.31±15.47)°和(125.35±17.11)°、膝关节活动度ROM分别为(139.68±16.69)°和(131.49±18.24)°,两组比较差异有统计学意义(P<0.05),骨折愈合时间分别为(5.42±0.87)个月和(6.28±1.07)个月,Harris评分分别为(83.49±9.31)分和(77.57±6.39)分,HSS评分分别为(85.35±6.90)分和(80.32±7.79)分,两组比较差异有统计学意义(P<0.05)。两组切口长度和并发症比较,差异无统计学意义。结论 相比于锁定加压钢板,桥接组合式内固定治疗股骨干粉碎性骨折的手术创伤更小,骨折愈合更快,术后功能更好。

政府主导下我国高素质农民培育效果比较研究

政府主导下的高素质农民培育是乡村人才振兴的重要途径。文章通过对我国四大经济区域高素质农民培育的横纵比较,结果显示:培育高素质农民的专项扶持政策力度总体有下滑趋势,区域差异不明显,但在普惠性金融政策上存在地区差异,西部地区呈现出贷款“高需求高满足”态势,东北地区表现出较强的农业保险购买力。高素质农民队伍壮大及其生产经营现代化发展带来的社会经济和生态效益在各地区都有一定程度的改观,东部地区经济效益最为显著,东北地区的培育效益总体低于东部和中西部地区。因此,亟需分区分类采取不同的倾斜政策,引导和激励高素质农民在乡村振兴和农业高质量发展中发挥“中坚力量”作用。

引江水净水厂夏季混凝工艺适用性运行研究

本文以夏季长江水为试验原水,开展工艺适用性小试、中试试验,在当前原水水质条件下,探讨2种不同混凝工艺的水处理效果。试验结果表明,斜管沉淀工艺与脉冲澄清工艺应对引江水均可以达到良好的混凝沉淀效果,可为后一步过滤工艺减轻运行负荷。两种工艺整体除浊效果接近,脉冲澄清工艺对有机物去除效果更好,斜管沉淀工艺应对低浊度原水的适应性更强。同时混凝效果对控制出厂水残余铝有重要作用,控制混凝沉淀出水浊度0.5 NTU以下,可有效控制沉后水残余铝0.15 mg/L以下,保证出厂水残余铝符合国家标准要求。

血流导向装置与传统支架治疗颈内动脉眼动脉段未破裂动脉瘤的疗效

目的比较血流导向装置与传统支架治疗颈内动脉眼动脉段未破裂动脉瘤的安全性与有效性。方法回顾性分析2017年1月至2023年1月中国人民解放军南部战区总医院神经外科应用支架辅助栓塞治疗的70例颈内动脉眼动脉段未破裂动脉瘤的临床资料。根据植入支架类型,分为血流导向装置组(n=21)和传统支架组(n=49),比较两组术后临床效果及并发症。结果两组患者随访3~24个月,平均(14.4±1.82)个月。围手术期及随访结果显示,血流导向装置组、传统支架组均能达到较高的动脉瘤闭塞率(93.3%vs.87.9%),差异无统计学意义(P>0.05);血流导向装置组相较于传统支架组,围手术期及短期并发症发生率低(0 vs.6.1%),并且血流导向装置组复发率也低于传统支架组(0 vs.6.1%),但差异无统计学意义(P>0.05)。结论血流导向装置与传统支架治疗颈内动脉眼动脉段未破裂动脉瘤均可行并且安全有效,初步研究结果表明血流导向装置治疗后短期并发症及再治疗发生率更低,手术时间短,但对于患者长期的并发症仍需要进一步研究验证。

体外冲击波联合关节静态牵伸训练治疗创伤后肘关节僵硬的临床观察

目的探讨体外冲击波联合关节静态牵伸训练治疗创伤后肘关节僵硬的临床疗效。方法选取2021年4月至2022年10月湖北医药学院附属襄阳市第一人民医院收治的创伤后肘关节僵硬的60例患者作为研究对象,按照随机数字表法分为冲击波组、牵伸组及联合治疗组,每组20例。三组患者均给予常规康复训练,冲击波组采用弹道式体外冲击波治疗,牵伸组采用肘关节静态牵伸训练治疗,联合治疗组采用上述两种方法联合治疗,疗程均为6周,治疗6周后评估三组患者肘关节主动活动度(AROM)及Mayo肘关节功能评分。结果治疗前,三组患者AROM、疼痛、运动、稳定性、日常活动功能评分比较,差异无统计学意义(P>0.05);治疗后,三组患者的AROM及肘关节Mayo肘功能评分均高于本组治疗前,且联合治疗组的上述指标高于冲击波组及牵伸组,差异有统计学意义(P<0.05)。三组患者治疗效果比较,差异有统计学意义(P<0.05)。结论在常规康复治疗的基础上,采用体外冲击波联合关节静态牵伸训练治疗创伤后肘关节僵硬,能够改善患肘的AROM及关节功能等,有利于上肢功能的恢复。