Expressive writing as a smoking cessation treatment adjunct for young adult smokers.

This investigation evaluated the efficacy of expressive writing as a treatment adjunct to a brief office smoking cessation intervention plus nicotine patch therapy in young adults. Participants aged 18-24 years were randomized to a brief office intervention (n=99) or to an expressive writing plus brief office intervention (n=97). Both conditions received four individual visits plus 6 weeks of nicotine patch therapy, which began on the quit date following the week 2 visit. Participants in the expressive writing plus brief intervention condition wrote for 2 consecutive days before and 3 consecutive days after the quit date. The brief office intervention group completed a control writing assignment. At end of treatment (week 8), biochemically confirmed 7-day point-prevalence abstinence for the expressive writing plus brief office intervention condition was significantly greater than for the brief office condition (33% vs. 20%, p=.043, OR=2.0, 95% CI=1.0-3.7, from a logistic regression adjusting for gender). At 24 and 52 weeks, abstinence rates were similar for the brief office intervention versus expressive writing plus brief office intervention (12% vs. 11% at 24 weeks; 11% vs. 11% at 52 weeks). The results suggest that expressive writing has promise as a smoking cessation treatment adjunct for young adults. Lengthier interventions or the use of boosters should be tested to extend treatment effects. However, participants reported a low level of enthusiasm for the expressive writing, which may be a barrier to implementing it over a longer time frame. Therefore, other modes of delivering expressive writing to young adult cigarette smokers should be explored.     

美国大杏仁对年轻吸烟者体重、血脂和血压的影响

目的本研究探讨了美国大杏仁对吸烟者体重、血脂和血压的影响。方法 60位健康年轻男性吸烟者摄入美国大杏仁,84 g/d,连续28 d。分别在试验前后测量体重和血压,并取血测定相关血脂指标,包括甘油三酯、总胆固醇和高密度脂蛋白。结果吸烟者摄入美国大杏仁28 d后,与摄入前相比,体重、血压和血脂均没有显著改变。结论连续28 d摄入84 g美国大杏仁对年轻健康吸烟者的体重、血压和血脂均没有明显影响。     

气调包装(MAP)对草莓保鲜的影响

研究了气调包装技术对草莓贮藏保鲜的效果。结果表明,草莓最佳气调贮藏的条件为2.5%O2 16%CO2,它能够把草莓的货架寿命延长4～6d;利用LDPE和PVC复合膜明显优于LDPE膜和PVC膜。气调贮藏效果表明,MAP能明显抑制草莓的呼吸作用和水分的蒸腾作用,抑制糖、酸和花色苷等物质的降解。最后研究了包装内气体组分的动态变化。     

食品包装光栅印刷中莫尔条纹的影响

在食品包装中,结合光栅材料光学性质和半色调图像加网技术,对光栅印刷莫尔条纹生成规律和防伪应用研究具有重要意义。采用理论计算的方法对莫尔条纹形成及分布特征进行分析,并通过实验对分析和计算进行验证。针对食品包装光栅印刷的实际情况,根据莫尔条纹形成规律,选择适宜的光栅印刷加网角度和网屏/光栅线数比,可以有效消除或减弱莫尔条纹的影响。     

Effects of preoperative smoking cessation on the incidence and risk of intraoperative and postoperative complications in adult smokers: a systematic review

Objectives

To establish the effect of preoperative smoking cessation on the risk of postoperative complications, and to identify the effect of the timing of preoperative cessation.

Data sources

The Cochrane Library Database, PsycINFO, EMBASE, Medline, and CINAHL databases were searched, using the terms: “smoking”, “smoking‐cessation”, “tobacco‐use”, “tobacco‐abstinence”, “cigarett$”, “complication$”, “postoperative‐complication$”, “preoperative”, “perioperative” and “surg$”. Further articles were obtained from reference lists. The search was limited to articles on adults, written in English and published up to November 2005.

Study selection

Prospective cohort designs exploring the effects of preoperative smoking cessation on postoperative complications were included. Two reviewers independently scanned abstracts of relevant articles to determine eligibility. Lack of agreement was resolved through discussion and consensus. Twelve studies met the inclusion criteria.

Data extraction

Methodological quality was assessed by both reviewers, exploring validation of smoking status, clear definition of the period of smoking cessation, control for confounding variables and length of follow‐up.

Data synthesis

Only four of the studies specified the exact period of smoking cessation, with six studies specifying the length of the follow‐up period. Five studies revealed a lower risk or incidence of postoperative complications in past smokers than current smokers or reported that there was no significant difference between past smokers and non‐smokers.

Conclusions

Longer periods of smoking cessation appear to be more effective in reducing the incidence/risk of postoperative complications; there was no increased risk in postoperative complications from short term cessation. An optimal period of preoperative smoking cessation could not be identified from the available evidence.     

不同阻隔性包装材料对生菜保鲜效果的影响

为了研究不同阻隔性包装材料对采后生菜保鲜效果的影响,选择低密度聚乙烯膜(LDPE)、聚乙烯膜(PE)、高密度聚乙烯膜(HDPE)、乙烯—乙烯醇共聚物/聚乙烯复合膜(EVOH/PE)4种包装材料对生菜进行气调包装,并设置无包装组作为对照,置于4℃的冷库中贮藏。贮藏期间,定期对各组生菜感官、失重率、叶绿素含量、相对电导率以及袋内气体组分等指标进行测定。结果表明,第6天时,对照组生菜因失水严重而失去商品价值;EVOH/PE组中O_2即将耗尽,CO_2比例达到20.3%,袋内出现酒精气味;其它3组袋内O_2比例均先降低,在小范围内呈波动性变化,CO_2比例先升高后相对平稳。HDPE组贮藏时间达18d,保鲜效果最好。阻隔性适宜的包装材料可以有效提高生菜的保鲜效果,延长保鲜期。     

不同包装材料对羊肚菌保鲜效果的影响

以人工种植羊肚菌为试材,采用3种包装(微孔膜、PE膜和透湿袋)在1℃下进行贮藏,定期测定其生理指标及感官品质,筛选最适于羊肚菌保鲜的包装材料。结果表明,与PE膜和透湿袋处理相比,微孔膜包装在贮藏期间可以更有效地减少羊肚菌质量损失,降低呼吸强度,减轻褐变程度,使可溶性固形物含量和多酚含量维持在较高水平,降低多酚氧化酶活性,保持较高的过氧化物酶活性。冷藏35 d,微孔膜包装的羊肚菌感官评分高于空白对照和其他包装材料处理组。微孔膜包装结合1℃冷藏处理是羊肚菌最佳保鲜方式,可以有效维持羊肚菌品质,延长贮藏期,在羊肚菌采后保鲜上具有较好的应用前景。     

Physical work-induced oxidative stress is exacerbated in young cigarette smokers.

Both cigarette smoking and strenuous physical work are associated with increased oxidative stress, which is implicated in the pathogenesis of cardiovascular disease. No study to date has measured oxidative stress in response to graded exercise in cigarette smokers. We compared oxidative stress biomarkers before and after strenuous exercise (Bruce treadmill protocol) in 14 cigarette smokers and 15 nonsmokers of similar age (24+/-6 years) and fitness status. Plasma protein carbonyls (PC), malondialdehyde (MDA), and 8-hydroxydeoxyguanosine (8-OHdG) were measured pre- and postexercise. Smoking status (p<.01) and time (p<.01) effects were noted for PC with values higher for smokers than nonsmokers and increasing from pre- to postexercise (52% vs. 25%, respectively). The smoking statusxtime interaction for PC approached statistical significance (p=.07). The change in PC from pre- to postexercise was positively correlated with the number of cigarettes smoked per day (r=.5782, p=.03). A smoking statusxtime interaction was noted for MDA (p<.01), with values increasing 37% from pre- (0.6140+/-0.0708 micromol/L) to postexercise (0.8440+/-0.0687 micromol/L) for smokers and remaining relatively unchanged for nonsmokers (from 0.7664+/-0.0901 to 0.7419+/-0.0776 micromol/L). 8-OHdG was unaffected by smoking status (p=.43) or exercise (p=.40). These findings indicate that young cigarette smokers experience an exaggerated oxidative stress response to strenuous physical work, compared with nonsmokers of similar age. These results highlight yet another detrimental impact of cigarette smoking on human health. Future investigations should focus on older, more established smokers.     

电离辐照杀菌对食品包装材料性能的影响

电离辐照处理包装材料已经成为现代包装杀菌最普遍的方法,它能够使塑料包装材料发生交联和降解反应。从电离辐照对食品包装杀菌的意义出发,分析电离辐射影响聚合物性能的机理;最后重点阐述电离辐射对几种商业用塑料包装材料的机械性能、塑料成分迁移量、阻隔性能及感官性能影响。     

Effects of emerging food processing techniques on the packaging materials

In recent years, new food processing techniques are attracting a lot of attention. Since some of these techniques might require the processing of foods inside their package, it is important to understand the interaction between the package and the process itself. The main objective of this article is to review the information in literature about the effects of different processing methods on: (i) the structural, mechanical and barrier properties of the materials commonly used in food packaging; and (ii) the migration behavior of additives mainly from plastic packaging films.     

气调包装对冷却鸭肉的保鲜效果研究

该文以0～4℃贮藏的冷却鸭肉为研究对象,以保鲜膜托盘包装为对照,通过分析肉色、pH值、蒸煮损失率、菌落总数、乳酸菌数、挥发性盐基氮(total volatile base nitrogen,TVB-N值)等指标,研究了30%CO_~(2+)70%N_2以及0. 4%CO+30%CO_~(2+)70%N_2气调包装(modified atmosphere packaging,MAP)对冷却鸭肉的保鲜效果。结果表明,与普通保鲜膜托盘包装相比,在贮藏的20 d内,2种气调包装方式均能抑制冷却鸭肉中微生物的生长,减少TVB-N的产生,从而显著延长了冷却鸭肉的货架期,具有较理想的保鲜效果。0. 4%CO气调包装没有起到进一步的抑菌效果,但在贮藏过程中鸭皮的L*值与a*值均高于其他2种处理组,并保持了产品的优良外观,具有良好的护色作用。综合分析,0. 4%CO+30%CO_~(2+)70%N_2气调包装对冷却鸭肉的保鲜效果最好。     

Effects of packaging atmospheres on shelf-life quality of ground ostrich meat

Fresh ground ostrich meat was packaged under high oxygen (O2), high nitrogen (N2), vacuum (VAC) and ambient air (AIR) atmospheres, stored at 4 ± 1 °C and displayed under 1700 ± 100 lux of fluorescent lighting for 9 days. The meat was evaluated for changes in typical shelf-life characteristics consisting of pH, color properties (CIE L^∗, a^∗, b^∗, and total color difference, ΔE), oxidative changes (thiobarbituric acid value and hexanal content) and bacterial counts (total viable cell, coliform, lactic acid bacteria, Enterobacteriaceae, Pseudomonas spp.) Initial meat pH was 6.16 and declined slightly during storage. TBA values and hexanal content were highest in O2 and lowest (P ? 0.05) in VAC and N2 atmospheres. Surface lightness (L^∗) and redness (a^∗) were highest in O2 packaging initially, decreasing (P ? 0.05) by day 9. ΔE of the ground ostrich increased during storage in only O₂ and AIR packaging. All packaging methods had generally similar effects on microbial outgrowth. Total aerobic bacteria attained >10⁶ CFU/g meat between day 3 and day 6. Ground ostrich meat was below saleable quality in less than 6 days based on all of the meat attributes. For O2 packaging however, quality based on lipid oxidation and color properties indicated a shelf-life of less than 3 days. Oxidation is likely the limiting factor for shelf-life of ground ostrich meat.     

托盘和真空包装对冷却羊肉品质的影响

为研究托盘和真空包装对冷却羊肉品质的影响,本实验采用PA/CPP、PA/PE两种真空包装材料和普通托盘在真空度0.08 MPa条件下分别对冷却羊肉进行包装,4℃条件贮藏20 d。通过对其储存过程中汁液流失率、p H、挥发性盐基氮值、色泽、菌落总数进行分析,揭示出两种包装方式对冷却羊肉品质影响的差异性。结果表明:在贮藏过程中,真空包装的汁液流失率显著高于普通托盘包装,但普通托盘包装的菌落总数和挥发性盐基氮值显著高于真空包装(p>0.05),且保质期短于真空包装。真空包装组中,PA/CPP组在贮藏过程中汁液流失率最低,但与PA/PE组差异不显著(p>0.05)。真空包装可以有效延长冷鲜肉的保质期,但PA/CPP和PA/PE对冷却羊肉品质的影响差异不显著(p>0.05)。      

气调包装对番石榴贮藏品质的影响

研究12℃时4%O2+5%CO2+91%N2的气调包装对番石榴贮藏品质的影响。与相同温度下未气调包装相比,气调包装能够延缓果实的软化,推迟果肉内过氧化物酶活性和还原糖含量的达峰时间,降低了VC和可滴定酸的分解速率,抑制了丙二醛的生成速率。结果表明,气调包装的番石榴保质期比未气调样品延长了一倍,其在番石榴贮藏保鲜中有一定的推广应用价值。     

不同包装方式对冷鲜鸡的保鲜效果

为研究A组(70%CO_2/30%N_2)、B组(50%CO_2/50%N_2)、C组(70%N_2/30%CO_2)、VP组(真空包装)和CK组(空气包装)5种包装方式对冷鲜鸡保鲜效果的影响,以新鲜的冷鲜鸡为原料,在4℃贮藏期间测定其感官特性、理化指标(p H值、色差、汁液流失率、TVB-N含量、TBA值)和微生物指标的变化。结果表明:A组(70%CO_2/30%N_2)比空气包装、真空包装和其他气调组更有利于维持冷鲜鸡的感官品质,同时能抑制冷鲜鸡中微生物生长繁殖,TVB-N含量的增加和TBA值的上升,较好地保持了p H值和肉样白度的稳定,从而延长货架期。综合保鲜效果为,A组B组=VP组C组CK组,对应的货架期分别为11、9、9、7和6 d。     

快递包装下采收成熟度对樱桃品质的影响

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不同气调贮藏对Mozzarella干酪功能特性的影响

采用无盐渍新工艺制得部分脱脂Mozzarella干酪,以PVDC为包装材料,分别采用50%CO2和50%N2,75%CO2和25%N2,100%CO2对干酪进行气调包装,以真空包装为对照组(CK),在4℃下进行冷藏,对不同气调贮藏条件下的Mozzarella的理化指标以及功能特性进行了测定.结果表明:各气调组水分含量、pH值、硬度、弹性均显著高于时照组(P<0.05),各气调组干酪的pH值为4.6 SN和质量分数为12%的TCA SN均显著低于对照组(P<0.05),各气调组与对照组相比,凝聚性、融化性无变化.b值逐步下降.各气调组保持了干酪特有的功能特性,感官评分均高于时照组.质量分数为75%的CO2和质量分数25%的N2能有效地延长Mozzarella干酪贮藏期.