1-MCP和MA包装南水梨果实贮藏效果的影响

以南水梨果实为试材,分别研究了1-MCP处理对市售白袋和绿袋包装果实的冷藏期和货架期贮藏的果肉硬度、可溶性固形物(TSS)、可滴定酸含量和细胞膜相对透性以及果心褐变、果实腐烂和果柄保鲜的影响.结果表明:1-MCP处理在贮藏前期对南水梨的硬度和酸含量有一定的保持作用,抑制果肉细胞膜透性升高,抑制了TSS升高,有利于果柄保鲜,抑制了果心褐变,但对腐烂无明显作用.白袋的保鲜效果优于绿袋.     

Carvedilol in dogs with dilated cardiomyopathy

BACKGROUND: Dilated cardiomyopathy (DCM) is characterized by reduced systolic function, heightened sympathetic tone, and high morbidity and mortality. Little is known regarding the safety and efficacy of beta-blocker treatment in dogs with DCM. HYPOTHESIS: Carvedilol improves echocardiographic and neurohormonal variables in dogs with DCM over a 4-month treatment period. METHODS: Prospective, placebo-controlled, double-blinded randomized study. Dogs with DCM underwent echocardiography, ECG, thoracic radiographs, and neurohormonal profiling, followed by titration onto carvedilol (0.3 mg/kg q12h) or placebo over a 4-week period and subsequently received 3 months of therapy. Primary study endpoints included left ventricular volume and function. RESULTS: Sixteen dogs received carvedilol and 7 received placebo. At study end, 13 carvedilol dogs and 5 placebo dogs were alive. There was no difference in the mean percentage change in left ventricular volume at end-diastole (LVVd), left ventricular end-systolic volume (LVVs), and ejection fraction (EF) between treatment groups, suggesting that both groups experienced similar amounts of disease progression. Carvedilol treatment did not result in significant changes in neurohormonal activation, radiographic heart size, heart rate, or owner perceived quality-of-life. Baseline B-type natriuretic peptide (BNP) predicted dogs in the carvedilol-treated group that maintained or improved their EF over the study duration. CONCLUSIONS AND CLINICAL IMPORTANCE: Carvedilol administration did not improve echocardiographic or neurohormonal indicators of heart function. The lack of effect may be related to severity of disease, carvedilol dose, or brevity of follow-up time. Statistical power of the present study was adversely affected by a high fatality rate in study dogs and small sample size.     

宜兴市官林污水处理厂工艺设计

介绍了宜兴市官林污水处理厂的工艺设计过程，该污水厂针对处理对象的水量和水质采用了循环式活性污泥法。     

苦马豆素抗血清治疗家兔小花棘豆中毒

通过检测苦马豆素（swainsonine,SW）抗血清治疗小花棘豆中毒家兔血清免疫和生化指标变化,评价SW抗血清对家兔小花棘豆中毒的治疗效果。将18只家兔随机分为对照组（6只）、攻毒组（6只）和攻毒治疗组（6只）,攻毒试验兔按干重拌料饲喂10g／（kg·d）小花棘豆草粉,攻毒组试验兔出现死亡时（第70天）停止攻毒。攻毒第21天,攻毒治疗组试验兔注射SW抗血清,每只兔每天0．5mL,连续注射4d。以攻毒试验开始进行首次采血,试验开始后每7d采血1次,进行血清免疫和生化指标测定。结果显示,攻毒第7天时攻毒家兔血清AKP活性和SW含量显著高于对照家兔（P〈0．05）;第14天时攻毒家兔血清AST和LDH活性显著高于对照家兔（P〈0．05）,血清AMA活性和E-玫瑰花环率均显著低于对照家兔（P〈0．05）;第21天时攻毒家兔血清BUN、CRE和GLU含量显著高于对照家兔（P〈0．05）。攻毒治疗组家免注射SW抗血清后血清AKP、LDH、AST、ALT活性及BuN、CRE、GLU、SW含量较攻毒家兔显著下降,AMA活性和E～玫瑰花环率显著上升。结果表明,SW抗血清可有效治疗家兔小花棘豆中毒。     

灰铸铁生产技术的一些新进展

对灰铸铁的研究现状和生产中的一些新技术做了评述。重点介绍了高强度薄壁灰铸铁的生产现状以及先进的制造工艺和先进的制造手段在灰铸铁生产中应用所取得的技术成果。     

厌氧氨氧化工艺在废水脱氮领域中的应用进展

厌氧氨氧化是一种全新的生物脱氮工艺。对于处理低碳氮比废水,与传统方法相比,它具有节省氧耗、无需外加有机碳源、污泥产量低等优点。近年来,随着基础研究的逐渐深入,各国学者开始将研究视角转向厌氧氨氧化工艺的实际应用。本文对该工艺在消化污泥上清液、垃圾渗滤液等实际废水脱氮研究中的进展进行了综述,并指出了目前存在的问题和今后的研究方向。     

Preliminary success using hydrogen peroxide to treat Atlantic salmon,Salmo salar L., affected with experimentally induced amoebic gill disease (AGD)

Currently, the only effective and commercially used treatment for amoebic gill disease (AGD) in farmed Tasmanian Atlantic salmon is freshwater bathing. Hydrogen peroxide (H₂O₂), commonly used throughout the aquaculture industry for a range of topical skin and gill infections, was trialled in vitro and in vivo to ascertain its potential as an alternative treatment against AGD. Under in vitro conditions, trophozoites of Neoparamoeba perurans were exposed to three concentrations of H₂O₂ in sea water (500, 1000 and 1500 mg L^?1) over four durations (10, 20, 30 and 60 min) each at two temperatures (12 and 18 °C). Trophozoite viability was assessed immediately post‐exposure and after 24 h. A concentration/duration combination of 1000 mg L^?1 for >10 min demonstrated potent amoebicidal activity. Subsequently, Atlantic salmon mildly affected with experimentally induced AGD were treated with H₂O₂ at 12 and 18 °C for 15 min at 1250 mg L^?1 and their re‐infection rate was compared to freshwater‐treated fish over 21 days. Significant differences in the percentage of filaments affected with hyperplastic lesions (in association with amoebae) and plasma osmolality were noted between treatment groups immediately post‐bath. However, the results were largely equivocal in terms of disease resolution over a 3‐week period following treatment. These data suggest that H₂O₂ treatment in sea water successfully ameliorated a clinically light case of AGD under laboratory conditions.     

Evaluating the use of garlic (Allium sativum) for the remedy of Cryptocaryon irritans in guppies (Poecilia reticulata)

Garlic (Allium sativum) has been shown to possess antimicrobial properties against a range of disease‐causing agents, including fish parasites. Our study aimed to investigate the potential use of garlic as a treatment against Cryptocaryon irritans infection, using guppies (Poecilia reticulata) as the fish model. Garlic was freeze‐dried, powdered, and used as it is or as an aqueous extract. The content of allicin, its main active ingredient, was 1.25 mg/g in garlic powder and 0.82 mg/ml in the aqueous extract, as determined by HPLC analysis. Aqueous garlic extract fully immobilized C. irritans theronts and protomonts within 20 and 40 min, respectively, following exposure to 5 µl/ml. Treatment trials were performed, in which infected fish were fed with garlic powder‐supplemented feeds (5%, 10%, or 20% supplementation), bathed in garlic aqueous extract (250 or 500 µl/L) and subjected to a combined treatment which included both feeding and bathing. Results revealed that the tested treatments failed to cure the infection, though reduction in infection intensity on the caudal fin, but not on the gills, was evident following dietary supplementation with 20% of powdered garlic in one of the trials.     

城市富营养化湖泊综合治理——以武汉北太子湖为例

应用"污染源控制+水生态修复+水质提升"综合技术治理北太子湖,为城市富营养化湖泊的治理提供技术体系和示范。北太子湖规划蓝线水面面积52.6 hm~2,湖岸线长5km,平均水深1.8 m,工程前水质整体为劣V类,治理目标是湖水水质达到地表水IV类。2018年3月-2019年2月,通过实施污水管网改造、初期雨水调蓄池修建、生态植草沟构建、污染底泥疏浚、湖体水生态系统构建、旁路人工湿地水体提标等工程措施,COD、TN、TP的去除率分别为58.14%、83.18%、90.91%;2019年6-8月水体COD、TN、TP连续3个月达到地表水IV类标准。建议在水生态修复工程完工后,投加一些生态环保型的水质净化剂,提升水体透明度,促进沉水植物快速生长繁殖以发挥净化水质的功能。     

‘丰香’草莓叶片高效再生体系的建立

 以草莓主栽品种丰香( Fragaria ×ananassa Duch ‘Toyonoka’) 叶片为外植体, 研究了影响组织培养的多个因素, 建立了高效再生体系。结果表明: MS + TDZ 1.5 mg·L ^{- 1} + IBA 0.4 mg·L ^{- 1}培养基最适于不定芽分化。不同滤光膜(绿膜、红膜、蓝膜、黄膜) 对草莓不定芽的分化具显著效应, 绿膜和红膜对芽的分化有明显促进作用, 不定芽再生率达95%以上, 平均每个外植体再生芽数在25个以上; 而蓝膜和黄膜则不利于芽的分化。不同滤光膜光谱差异主要集中在300～700 nm, 红、绿膜在该波段光强较弱,而黄、蓝膜和荧光灯较强。暗处理4周比1、2、3周更有利于提高叶片的不定芽再生率, 此后转到光下培养, 获得的不定芽再生率可达100%。