The impact of migration on the food consumption and nutrition of left-behind family members: Evidence from a minority mountainous region of southwestern China

While migration is widely recognized as a valid option for improving farmers’ income, the welfare effects of migration on left-behind family members are ambiguous. This study examines the impacts of migration on left-behind family members’ food consumption and nutrient intake, particularly in remote rural areas in China. Based on household survey data collected from 611 smallholder rubber farmers in Xishuangbanna Dai Autonomous Prefecture of southwestern China, the empirical results suggest that the migration of family members contributes to improving household net income, whereas it negatively affects left-behind family members’ consumption of grain and pork. Migration also leads to a decrease in left-behind family members’ nutrient intake. Surprisingly, the economic returns of farmers’ migration not only do not foster the transformation of household food consumption from a staple food-dominated dietary structure to one including more meat and dairy products but also reduce left-behind family members’ nutrient intake. This study adds to the literature on the impact of farmers’ migration. The findings have important implications for better understanding the impacts of migration on farmers’ livelihood and human capital development in rural China.

农产品区域公用品牌助力乡村产业振兴:理论逻辑、现实挑战与实践路径

农产品区域公用品牌建设通过提高农产品竞争力和推动乡村产业结构调整为实现乡村产业振兴注入新动能。本文从资源配置效应、规模经济效应、结构升级效应、品牌经济效应和协同共享效应五个维度厘清了农产品区域公用品牌建设与乡村产业振兴之间的理论逻辑,剖析了农产品区域公用品牌助力乡村产业振兴面临的现实挑战,并据此提出了相对应的实践路径。研究发现,农产品区域公用品牌建设与维护难度大、市场竞争日趋激烈、生产能力和管理水平低、品牌难以有效运作等是制约农产品区域公用品牌助力乡村产业振兴实现的关键因素。为此,本文提出多措施推进品牌建设、全过程确保品牌品质、全方位优化供应管理和多方面加大政策支持,以提升农产品区域公用品牌建设助力乡村产业振兴的效率。

交通条件改善对农户生活能源绿色转型的影响——基于西南山区农户面板数据

推动农村地区能源转型是全面推进乡村振兴、实现碳达峰碳中和目标的必然之举。基于西南山区农户面板数据,联合使用随机效应二值选择模型和Mundlak方法,实证检验了交通条件改善对农户生活能源绿色转型的影响。研究发现交通条件改善对农户生活能源绿色转型具有显著促进作用,农村道路硬化使得农户采用绿色生活能源的概率提高了5.45%。机制分析表明交通条件改善通过提高农户家庭收入和传播现代生活方式,从而促进农户生活能源绿色转型。异质性分析发现对于户主教育水平较高和居住在远离乡镇地区的农户,交通条件改善对其生活能源绿色转型发挥了更大作用。从供给侧视角补充了影响农户生活能源绿色转型的重要因素,为改善交通基础设施建设进而推动农村地区生活能源绿色转型的政策设计提供了参考。

“双循环”背景下我国粮食安全韧性及风险管控战略研究

保障国家粮食安全是建设现代农业强国的重要基础,在“双循环”背景下探讨增强我国粮食安全韧性及风险管控能力,兼具理论价值和现实意义。本文阐释了“双循环”背景下粮食安全韧性及风险管控的科学内涵,剖析了当前我国粮食安全韧性及风险管控能力的现状与特点、影响因素和可行路径。研究认为,农业生产基础条件、粮食生产科技水平、粮食生产方式、粮食生产支持政策、国际贸易环境是影响粮食安全韧性及风险管控能力的关键因素;提高粮食供应的稳定性、提升粮食生产的抗逆性、加强粮食生产的可持续性、保持政策制度的连贯性、增强国内与国际市场的协同性是增强粮食安全韧性及风险管控能力的可行路径。为此建议,筑牢粮食产能基础、提升粮食技术支撑、强化智能监测管理、加快保障制度建设、优化粮食进出口贸易,以此增强“双循环”背景下我国粮食安全韧性及风险管控能力。

增塑剂对聚氯乙烯溶胶凝胶塑化流变性能的影响

研究了不同增塑剂制备的聚氯乙烯(PVC)溶胶复数黏度(η)随温度或时间的流变性能变化情况,并探讨了引起流变性能差异的原因。结果表明,随温度升高或时间延长,η呈先降低,后由缓慢上升至急速上升,形成1个肩峰并达到最大值,最后又逐步减小的非正态分布趋势。各PVC溶胶在流变曲线的前3个阶段,η差异明显——第1阶段,η主要与增塑剂黏度成正比;第2、第3阶段——η主要与增塑剂的增塑效率和溶解度参数有关;第4阶段——约在160℃或30min后,各流变曲线趋于重合,η的大小无明显差异。

不同加工方法对乙烯-辛烯共聚物/聚乳酸共混物相结构与性能的影响

采用普通共混方法及原位微纤技术制备了乙烯-辛烯共聚物(POE)/聚乳酸(PLA)共混物,通过扫描电镜、力学性能测试和动态流变性能测试对材料形貌及性能进行表征。结果表明,对于POE/PLA普通共混物,PLA以球形颗粒分布在POE基体中,材料的拉伸应力-应变曲线无明显的屈服行为,PLA质量分数为20%时,材料拉伸强度为6.6 MPa;PLA的加入提高了材料的储能模量(G′)和损耗模量(G″)。对于POE/PLA微纤共混物,PLA在POE中形成了PLA微纤,当微纤的质量分数为10%时,材料的拉伸应力应变呈现双屈服行为,随微纤含量增加双屈服行为更明显。POE-20试样在应变为23%发生第1次屈服,在应变为240%发生第2次屈服,材料拉伸强度为8.8 MPa,其拉伸强度比相同PLA含量的普通共混物高33.3%,G′在低频区出现1个平台。

Tos改良联合进路钛听骨植入鼓室成形的疗效观察

目的观察符合条件的慢性化脓性中耳炎患者行Tos改良联合入路清理病变并一期植入钛人工听骨行鼓室成形的效果。方法回顾性分析34例在该院施行Tos改良联合入路乳突开放并植入钛人工听骨行鼓室成形的慢性化脓性中耳炎病例,总结患者手术前后听力及影像学特点,观察手术前后言语频率气导听阈变化。结果以术中听骨破坏情况分组,镫骨板上结构缺失组植入全听骨赝复体(TORP)后听力改善(36.25±6.12)dB HL;砧蹬关节中段组植入部分听骨赝复体(PORP)后听力改善(13.18±3.37)dB HL。术后无钛听骨移位、感染,听力改善有效率97.06%(P<0.05)。1~3个月全部干耳。结论 Tos改良联合入路鼓室成形并一期植入钛人工听骨能有效地清理中耳病变,尤其是清理后鼓室的隐匿病变,并有效提高听力,术前高分辨率CT(HRCT)发现乳突气化不良,尤其有乙状窦前移、脑板低位和面神经低位等不利于暴露的解剖变异时,可优先选择此术式。

盐酸羟考酮缓释片12小时滴定方案用于中重度癌痛患者的有效性和安全性-前瞻性随机开放多中心平行对照研究

目的:阿片类药物是中、重度癌痛治疗的首选药物。目前以缓释阿片类药物为背景的滴定方法的剂量调整时机和方式还需进一步探索。本研究旨在评估盐酸羟考酮缓释片12 h滴定方案用于中重度癌痛患者的有效性和安全性。方法:选择2018年2月至2019年12月浙江省24家医院收治的中重度阿片类药物未耐受癌痛患者114例[数字分级法(numerical rating scale,NRS)≥4分]作为研究对象。筛选出合并1次以上爆发痛且存在中重度以上疼痛(NRS≥4分)患者87例,按盐酸羟考酮缓释片调整的时间不同分为试验组(12 h滴定组,n=45)和对照组(24 h滴定组,n=42)。试验组起始给予盐酸羟考酮缓释片10 mg并根据疼痛情况给予即释吗啡补救镇痛,12 h后根据即释吗啡量调整剂量,剂量调整为背景剂量+12 h内即释吗啡剂量。对照组起始剂量给予盐酸羟考酮缓释片10 mg q12h,并根据疼痛情况给予即释吗啡补救镇痛,24 h后剂量调整为背景剂量+24 h内即释吗啡剂量/2。比较两组24、48、72 h的疼痛缓解率、不良反应发生率、即释吗啡补救镇痛情况及使用量、生活质量评分,以及镇痛满意度。结果:给药后24、48、72 h,试验组和对照组均显示出较高的疼痛缓解率,组间比较差异无统计学意义(P>0.05)。相对于对照组,试验组在24、48及72 h补救镇痛次数及剂量均显著减少(P<0.05)。两组患者不良反应大多数为轻中度,发生率比较差异无统计学意义(P>0.05)。镇痛满意度水平均较高,组间比较差异无统计学意义(P>0.05)。结论:在中重度癌痛患者应用盐酸羟考酮缓释片为背景的滴定方案中,12 h调整剂量能有效减少补救镇痛次数及剂量,维持较高的镇痛缓解率和镇痛满意度,安全性良好。

鼻内镜下扁桃体腺样体等离子切除术对重度鼾症所致发育不良的治疗效果

目的探讨扁桃体腺样体重度肥大阻塞气道、引起睡眠鼾症而致身高和(或)体重发育不达标的患儿,进行鼻内镜下等离子扁桃体腺样体切除术后1年,其生长发育达标的情况。方法随访因扁桃体腺样体重度肥大引起睡眠鼾症导致身高和(或)体重发育不达标的患儿47名,收集其术前病史,包括睡眠质量、有无缺氧、发育情况、精神注意力和手术情况,并记录术前和术后6个月、术后1年身高和体重达标情况,统计分析身高体重术前术后的增长情况和达标率。结果患儿年龄2～5岁,平均月龄(48.45±11.36)个月,术前均有严重的睡眠打鼾,伴有张口呼吸和睡眠呼吸暂停41例(87.2%),白天注意力不集中35例(74.5%),进行鼻内镜扁桃体腺样体等离子切除术,术后6个月和1年身高增长平均为(6.27±1.73)和(11.88±2.35)cm,体重增长分别为(1.96±0.42)和(3.58±0.79)kg。术后1年身高体重按标准,身高达标40例(85.11%),体重达标36例(76.60%),均达标32例(68.09%)。结论儿童鼾症会影响患儿身高体重发育,尤其是重度阻塞,经鼻内镜扁桃体腺样体等离子切除术后,可促进恢复生长发育,有手术指征的患儿应尽早手术,以免耽误儿童黄金生长发育期。

Interleukin-8, a promising predictor for prognosis of pancreatic cancer

AIM: To investigate the value of interleukin-8 (IL-8), a pro-inflammatory chemokine, in predicting the prognosis of pancreatic cancer. METHODS: Expression of IL-8 and its receptor CXCR1 was assessed by immunohistochemistry in pancreatic cancer and chronic pancreatitis samples. Enzyme-linked immunosorbent assay was used to detect the serum IL-8 levels in pancreatic cancer patients. Human pancreatic cancer tissues were heterotopically transplanted to the immune-deficiency mice to evaluate the effect of serum IL-8 on the tumorigenesis of the cancer samples.RESULTS: IL-8 and CXCR1 proteins were both overexpressed in pancreatic adenocarcinoma samples (55.6% and 65.4%, respectively) compared with the matched para-cancer tissues (25.9% and 12.3%, P < 0.01), or chronic pancreatitis (0% and 25%, P < 0.05). Serum IL-8 levels in pancreatic cancer patients (271.1 ± 187.7 ng/mL) were higher than in other digestive system tumors, such as gastric cancer (41.77 ± 9.11 ng/mL, P = 0.025), colorectal carcinoma (78.72 ± 80.60 ng/mL, P = 0.032) and hepatocellular carcinoma (59.60 ± 19.80 ng/mL, P = 0.016). In vivo tumorigenesis analysis further proved that tumor tissues from patients with higher serum IL-8 levels grew faster than those with lower IL-8 levels. CONCLUSION: IL-8 can be a fine serum marker for predicting the prognosis pancreatic cancer.

Expression of fibroblast activation protein in human pancreatic adenocarcinoma and its clinicopathological significance

AIM: To examine fibroblast activation protein (FAP) expression in pancreatic ductal adenocarcinoma (PDAC) and to analyze its relationship with the clinicopathology of PDAC. METHODS: FAP expression was examined in 134 PDAC specimens by immunohistochemistry, and in four pancreatic cancer cell lines (SW1990, Miapaca-2, AsPC-1 and BxPC-3) by Western blotting assay. We also analyzed the association between FAP expression in PDAC cells and the clinicopathology of PDAC patients. RESULTS: The results showed that the FAP was expressed in both stromal fibroblast cells (98/134, 73.1%) and carcinoma cells (102/134, 76.1%). All 4 pancreatic cancer cell lines expressed FAP protein at different levels. Protein bands corresponding to the proteolytically active 170-kDa seprase dimer and its88-kDa seprase subunit were identif ied. Higher FAP expression in carcinoma cells was associated with tumor size (P < 0.001), fi brotic focus (P = 0.003), perineural invasion (P = 0.009) and worse clinical outcome (P = 0.0085). CONCLUSION: FAP is highly expressed in carcinoma cells and f ibroblasts in PDAC tissues, and its expression is associated with desmoplasia and worse prognosis.

Salt-responsive genes in rice revealed by cDNA microarray analysis

We used cDNA microarrays containing ～9,000 unigenes to identify 486 salt responsive expressed sequence tags (ESTs) (representing ～450 unigenes) in shoots of the highly salt-tolerant rice variety, Nona Bokra (Oryza sativa L. Ssp.Indica pv. Nona). Some of the genes identified in this study had previously been associated with salt stress. Howeverthe majority were novel, indicating that there is a great number of genes that are induced by salt exposure. Analysis of the salt stress expression profile data of Nona provided clues regarding some putative cellular and molecular processes that are undertaken by this tolerant rice variety in response to salt stress. Namely, we found that multiple transcription factors were induced during the initial salt response of shoots. Many genes whose encoded proteins are implicated in detoxification, protectant and transport were rapidly induced. Genes supporting photosynthesis were repressed and those supporting carbohydrate metabolism were altered. Commonality among the genes induced by salt exposure with those induced during senescence and biotic stress responses suggests that there are shared signaling pathways among these processes. We further compared the transcriptome changes of the salt-sensitive cultivar, IR28, with that of Nona rice. Many genes that are salt responsive in Nona were found to be differentially regulated in IR28. This study identified a large number of candidate functional genes that appear to be involved in salt tolerance and further examination of these genes may enable the molecular basis of salt tolerance to be elucidated.

小农生产中的农业社会化服务需求：来自百乡万户调查数据

农业社会化服务体系会随着经济与市场发展及农业生产规模的变化而不断发展,是农业生产者抵御自然风险和市场风险的有效方式。基于农业部“百乡万户调查”农户调研数据,通过描述性统计与计量经济模型实证分析小农生产中的农业社会化服务需求,探讨可能引起农户在不同农业生产环节具有差异性服务需求的因素,特别是估计农户资源禀赋与农户在不同农业生产环节中的社会化服务需求的关系。研究结果表明:农户对农业社会化服务的需求主要集中在技术、生产信息、良种和生产资金等服务上;家庭劳动力分配与人均耕地面积不同的农户对不同农业生产环节的社会化服务需求具有异质性。最后提出进一步完善我国农业社会化服务体系的政策建议。

Givinostat inhibition of hepatic stellate cell proliferation and protein acetylation

AIM: To explore the effect of the histone deacetylase inhibitor givinostat on proteins related to regulation of hepatic stellate cell proliferation.METHODS: The cell counting kit-8 assay and flow cytometry were used to observe changes in proliferation, apoptosis, and cell cycle in hepatic stellate cells treated with givinostat. Western blot was used to observe expression changes in p21, p57, CDK4, CDK6, cyclin D1, caspase-3, and caspase-9 in hepatic stellate cells exposed to givinostat. The scratch assay was used to analyze the effect of givinostat on cell migration. Effects of givinostat on the reactive oxygen species profile, mitochondrial membrane potential, and mitochondrial permeability transition pore opening in JS-1 cells were observed by laser confocal microscopy.RESULTS: Givinostat significantly inhibited JS-1 cell proliferation and promoted cell apoptosis, leading to cell cycle arrest in G0/G1 phases. Treatment with givinostat downregulated protein expression of CDK4, CDK6, and cyclin D1, whereas expression of p21 and p57 was significantly increased. The givinostat-induced apoptosis of hepatic stellate cells was mainly mediatedthrough p38 and extracellular signal-regulated kinase 1/2. Givinostat treatment increased intracellular reactive oxygen species production, decreased mitochondrial membrane potential, and promoted mitochondrial permeability transition pore opening. Acetylation of superoxide dismutase(acetyl K68) and nuclear factor-κB p65(acetyl K310) was upregulated, while there was no change in protein expression. Moreover, the notable beneficial effect of givinostat on liver fibrosis was also confirmed in the mouse models.CONCLUSION: Givinostat has antifibrotic activities via regulating the acetylation of nuclear factor-κB and superoxide dismutase 2, thus inhibiting hepatic stellate cell proliferation and inducing apoptosis.

Impacts of the COVID-19 pandemic on consumers’ food safety knowledge and behavior in China

This study assesses the impacts of the COVID-19 pandemic on Chinese residents’food safety knowledge and behavior,and explores the possible influence mechanism,namely,focus on media information.The study is based on internet survey data of 1373 residents in China.A series of econometric models are developed to estimate food safety knowledge and behavior of residents.Both the descriptive and econometric results indicate that the existence of COVID-19 cases in a community has a significantly positive effect on residents’food safety knowledge and behavior.Residents focusing on food safety-related information tend to have higher food safety knowledge and practice food safety behavior.When controlling the variable focused on food safety-related information,the marginal effects of the existence of COVID-19 cases in a community on residents’food safety knowledge and behavior significantly decrease.However,the decrease in consumers’food safety knowledge is quite minor.Hence,the COVID-19 pandemic indeed improves Chinese residents’food safety knowledge and behavior,while focus on food safety-related information is an important mechanism for improving food safety behavior.Moreover,the estimation results of the simultaneous equations model reveal that consumers’food safety knowledge has a significant and positive effect on their food safety behavior.Heterogeneous impacts of the COVID-19 pandemic on residents’food safety knowledge and behavior among different regions and income groups are observed.The findings of this study provide evidence that public health events could enhance residents’safety awareness and behavior,while residents’focus on relevant information plays an important role in improving knowledge and impacting behavior.

贸易便利化对加工农产品出口质量的影响——以中国和“一带一路”沿线国家(地区)出口为例

出口技术复杂度提高是产品出口质量升级的一种体现,贸易便利化对于促进出口质量可能有显著影响,然而现有文献对中国加工农产品出口质量关注不够。本文基于2008—2019年中国和“一带一路”沿线国家(地区)出口加工农产品数据,分析贸易便利化对加工农产品出口质量的影响。实证结果显示:贸易便利化显著促进了加工农产品出口质量的提升,并且主要通过港口效率提升、监管环境改变等渠道提升加工农产品出口质量。异质性分析结果显示:对于不同地理位置、经济基础国家(地区)和不同产品来说,贸易便利化对加工农产品出口质量均产生显著影响,但影响大小存在一定差异。本文在一定程度上丰富了关于贸易便利化与加工农产品出口质量的研究,并具有一定的政策含义。

Glycyrrhizic acid promotes sciatic nerves recovery in type 1 diabetic rats and protects Schwann cells from high glucose-induced cytotoxicity

The present study aims to investigate the therapeutic effect and mechanism of glycyrrhizic acid(GA)in diabetic peripheral neuropathy(DPN).GA significantly mitigated nerve conduction velocity(NCV)deficit and morphological abnormality and reduced high-mobility group box-1(HMGB1)expression in the sciatic nerves of diabetic rats independent of blood glucose and body weight.Notably,GA alleviated the increase of HMGB1 and the decrease of cell viability in high glucose-stimulated RSC96 cells.Furthermore,GA obviously reduced the concentration of inflammatory cytokines in the sciatic nerves of diabetic rats and supernatants of high glucose-exposed RSC96 cells,then restored the decreased expression levels of nerve growth factor(NGF)and neuritin-1,and the increased expression levels of cleaved caspase-3 and neuron-specific enolase.Additionally,GA markedly inhibited receptor for advanced glycation end products(RAGE)expression,p38MAPK phosphorylation,and the nuclear translocation of NF-κBp65 in diabetic rats and high glucose-exposed RSC96 cells.The promotional effect of high glucose in RSC96 cells was diminished following Hmgb1 siRNA treatment.Our findings indicate that GA may exert neuroprotection on DPN by suppressing HMGB1,which lead to extenuation of inflammation response,balance of NGF,neuritin-1 and caspase-3,as well as inactivation of RAGE/p38MAPK/NF-κBp65 signaling pathway.

Signal transduction mechanism of TRB3 in rats with non-alcoholic fatty liver disease

AIM： To evaluate the possible role of Tribble 3 （TRB3） in a rat model of non-alcoholic fatty liver disease （NAFLD） and its signal transduction mechanism.METHODS： Thirty Sprague-Dawley rats were randomized into three groups： normal control group, non-alcoholic fatty liver group A （fed on a high-fat diet for 8 wk） and group B （fed on a high-fat diet for 16 wk）. To determine the degree of hepatic steatosis in rats of each group, livers were stained with hematoxylin and eosin, and evaluated; real-time fluorescent quantitative reverse transcriptase-polymerase chain reaction was performed to measure the expression levels of TRI33 mRNA, and Western blotting analysis was done to determine the expression levels of protein kinase B （Akt） and phosphorylated protein kinase B （p-Akt-Thr308, p-Akt-Ser473）.RESULTS： Hepatic steatosis was evident in both NAFLD groups： mild to moderate hepatic steatosis occurred in group A, mainly as mild steatosis.Moderate to severe hepatic steatosis occurred in group B, mainly as severe steatosis. The expression level of TRB3 mRNA in group B was significantly higher than in the control group （122.28 ± 95.37 vs 3.06 ± 2.33,P = 0.002） and group A （122.28 ± 95.37 vs 5.77 ± 4.20,P = 0.001）. There was no significant difference in the expression levels of Akt （1.03 ± 0.53 vs 1.12 ± 0.77,P = 0.729） and p-Akt-Thr308 （0.82 ± 0.45 vs 0.92 ± 0.38, P = 0.592） between group A and the control group. The expression level of Akt and p-Akt-Thr308 in group B was significantly lower than in group A （Akt 0.41 ± 0.16 vs 1.12 ± 0.77, P = 0.008; p-Akt-Thr308 0.47 ± 0.19 vs 0.82 ± 0.45, P = 0.036） and the control group （Akt 0.41 ± 0.16 vs 1.03 ± 0.53, P = 0.018;p-Akt-Thr308 0.47 ± 0.19 vs 0.92 ± 0.38, P = 0.010）.The expression level of p-Akt-Ser473 in group A was significantly higher than in group B （1.48 ± 0.50 vs 0.81± 0.39, P = 0.041） as well as the control group （1.48 ± 0.50 vs 0.45 ± 0.26, P = 0.003）.CONCLUSION： TRB3 blocks insulin signaling by inhibiting Akt activation, which contributes to insulin resistance. It may be an important factor in the occurrence and development of NAFLD.

The methyl jasmonate-responsive transcription factor SmMYB1 promotes phenolic acid biosynthesis in Salvia miltiorrhiza

Water-soluble phenolic acids are major bioactive compounds in the medicinal plant species Salvia miltiorrhiza.Phenolic acid biosynthesis is induced by methyl jasmonate(MeJA)in this important Chinese herb.Here,we investigated the mechanism underlying this induction by analyzing a transcriptome library of S.miltiorrhiza in response to MeJA.Global transcriptome analysis identified the MeJA-responsive R2R3-MYB transcription factor-encoding gene SmMYB1.Overexpressing SmMYB1 significantly promoted phenolic acid accumulation and upregulated the expression of genes encoding key enzymes in the phenolic acid biosynthesis pathway,including cytochrome P450-dependent monooxygenase(CYP98A14).Dual-luciferase(dual-LUC)assays and/or an electrophoretic mobility shift assays(EMSAs)indicated that SmMYB1 activated the expression of CYP98A14,as well as the expression of genes encoding anthocyanin biosynthesis pathway enzymes,including chalcone isomerase(CHI)and anthocyanidin synthase(ANS).In addition,SmMYB1 was shown to interact with SmMYC2 to additively promote CYP98A14 expression compared to the action of SmMYB1 alone.Taken together,these results demonstrate that SmMYB1 is an activator that improves the accumulation of phenolic acids and anthocyanins in S.miltiorrhiza.These findings lay the foundation for in-depth studies of the molecular mechanism underlying MeJA-mediated phenolic acid biosynthesis and for the metabolic engineering of bioactive ingredients in S.miltiorrhiza.