Combined effect of gamma radiation,hot water and sodium bicarbonate on quality and chemical constituents of stored mandarin fruits

The combined effect of gamma radiation and both hot water and sodium carbonate on physiological decay and chemical constituents of stored mandarin fruits was investigated in this work. In this consideration, the studied fruits were gamma irradiated at doses of 0, 0.3, 0.6, 1.2 and 2.4 KGy. Then, the irradiated and non-irradiated fruits were treated either by hot water or sodium bicarbonate to examine their capacity to give a further maintenance and increasing shelf life or storage periods of mandarin. Treated and non-treated fruit samples were taken at intervals of 10 days and up to 60 days. Physiological decay, total acidity, vitamin C, total sugars and TSS were investigated during the different intervals. Gamma radiation treatments showed a promising effect for maintaining the studied fruits and retarding the development of decay. On the other hand, applying both hot water and sodium bicarbonate as a further combined treatments induced a powerful effect on delaying decay development, keeping the chemical constituents near to the normal level and in turn maximizing shelf life and storage periods of the fruits under investigation.     

γ-射线辐射对银杏种子贮藏期间呼吸速率及品质的影响

以贮藏于４℃下的广东南雄产银杏（Ｇｒｉｎｋｇｏ ｂｉｌｏｂａ Ｌ．）种子为材料,去外种皮后用３０００ｒａｄ ＾６０Ｃｏγ－射线照射。结果表明：＾６０Ｃｏγ－射线辐射处理后,明显抑制银杏种子的呼吸速率,延缓种子萌发对呼吸高峰的出现,降低种仁中淀粉酶的活力,减缓淀粉转化为还原糖的速度,但对银杏种仁蛋白质、Ｖｃ含量没有明显的影响。     

Biocide application for increasing storage periods and maintaining quality and chemical constituents of banana fruits

Banana fruits were treated with biocides formulated from essential oils of anise, coriander or black cumin seeds. Treated and non-treated fruits were stored at temperatures of 5, 10, 15 and 20°C. Samples were stored for periods of 10, 20, 30, 40, 50 and 60 days. The collected samples in each interval were subjected to estimation of decay development and quality degree, in addition to the chemical constituents of starch, sugars, vitamin C of pulp and peel chlorophyll content. Results reveal that non-treated banana fruits decayed continuously by lapse of storage periods. However, this decay was significantly delayed by lowering the storage temperature. Soaking banana fruits in the tested biocides showed a positive potential for interrupting the decay in stored banana fruits and this promising impact was much more pronounced at lower storage temperature. Further, biocide treated banana fruits kept their good quality for longer storage periods compared to non-treated fruits, due to lower ripening rates which promisingly prolonged shelf-life. As the starch content gradually decreased during storage, the total sugar content increased. On the other hand, biocide application retarded the conversion of starch into simple sugars, especially at the low temperature rate. Additionally, the imposed treatments maintained vitamin C in banana pulp and lowered the decline in peel chlorophyll content.     

The effect of gamma radiation and N-ethyl-N-nitrosourea on cultured maize callus growth and plant regeneration

Regenerable maize calli of two inbred lines were exposed to 0 to 100 Gy of gamma rays or treated with 0 to 30 mM of N-ethyl-N-nitrosourea (ENU) to determine their effect on growth and plant regeneration capability. Both growth and plant regeneration capacity decreased with increasing levels of either gamma radiation or ENU; however, plant regeneration capacity was more sensitive to either agent than growth. The 50% inhibition dose (I₅₀) for callus growth (fresh-weight gain) was approximately 100 Gy of gamma radiation and 30 mM ENU. The I₅₀ for plant regeneration capacity of treated callus was approximately 25 Gy of gamma radiation and 2.5 mM ENU. The decrease in plant regeneration capacity correlated with a change in tissue composition of the treated callus from a hard, yellow and opaque tissue to a soft, grayish-yellow and translucent tissue. This change was quantified by measuring the reduction of MnO₄^- to MnO₂ (PR assay) by the callus. These results suggest that the effect of gamma radiation or ENU on plant regeneration capacity must be taken into consideration if these potentially mutagenic agents are to be used on maize callus cultures, for the purpose of producing useful mutations at a whole plant level. The data also suggest that the PR assay may be useful for predicting the actual plant regeneration capacity of maize callus.Abbreviations g f.w. gram fresh weight - ENU N-ethyl-N-nitrosourea - PR assay permanganate reduction assay - I₅₀ 50% inhibition dose     

典型森林生态系统总辐射和光合有效辐射长期观测中的仪器性能衰变和数据校正

利用中国通量网( ChinaFLUX)4个森林台站(长白山、千烟洲、鼎湖山和西双版纳)2003-2008年总辐射和光合有效辐射(PAR)观测资料,研究了CNR1总辐射表和Li-190SB光量子仪在长期观测中可能出现的不确定性和仪器性能变化等问题.结果表明:98％以上的CNR1总辐射观测精度满足技术标准,但在西双版纳站,CNR1观测的总辐射(QCNR1)比高精度短波辐射仪CM11观测的总辐射(QCM11)平均低7％;虽然温度对CNR1观测的总辐射有一定影响,但其影响大都在仪器允许的精度范围内,在西双版纳站,CNR1除了受温度影响外,还受到热带雨林特有的季节性雾的影响;通过分析光合有效辐射数据(特别是其与总辐射比值)的长期变化发现,光量子仪Li-190SB的性能衰减较明显,平均年衰减率达4％左右,为了校正PAR仪器性能衰减产生的系统误差,本文尝试给出了PAR的后期补偿校正方法,该方法可基本消除由于野外长期使用所造成的Li-190SB性能衰减.     

Inactivation of Paecilomyces fumosoroseus conidia by diffuse and total solar radiation

Abstract: The detrimental photic effects of natural solar radiation on the conidial persistence of the entomopathogenic hyphomycete Paecilomyces fumosoroseus were investigated by exposing quiescent conidia either to total solar radiation or to its diffuse component. A given amount of UVB diffuse radiation was found to be as detrimental, and sometimes twice as detrimental, as the same amount of total solar radiation. The variability in quantity and spectral distribution of the diffuse component of UVB solar radiation reaching the earth's surface, observed through spectral measurements, may be responsible for the difference in biological effects.     

Human interferon gamma: significance of the C-terminal flexible domain for its biological activity

The significance of the C-terminal part of human interferon gamma (hIFNgamma) for its biological activity was studied by 3(')-end gene mutagenesis. A series of nine derivative genes obtained by systemic deletion of three codons was constructed and expressed in Escherichia coli LE392. It was shown that the yield of recombinant protein gradually decreased and the solubility gradually increased with truncation of the C terminus. To avoid artifacts related to the imperfect folding of the proteins during purification, the biological activity of the hIFNgamma proteins was measured in clear cell lysates containing the soluble fractions only. The deletion of the C terminus had a two-step effect on both hIFNgamma antiviral and antiproliferative activities. Whereas the removal of the last 3, 6, and 9 C-terminal amino acids led to a gradual increase (up to 10 times) in biological activity of hIFNgamma, the deletion of more than 9 amino acids had an opposite effect. The truncation of the whole unstructured C-terminal domain resulted in a 10-fold decrease (but not in a complete loss) in biological activity of hIFNgamma. The latter was sequestered upon deletion of 24 amino acids, 3 of which belonged to the alpha-helical domain F.     

丙型肝炎病毒分片段抗体检测蛋白质芯片质控参比品的建立及质量验证

建立能同时检测丙型肝炎病毒(HCV)嵌合抗体、核心抗体和NS3、NS4、NS5抗体的蛋白质芯片质控参比品,对质控合格的芯片进行质量验证。用3种HCV EIA试剂分别检测从3家医院收集的丙型肝炎病毒感染患血清及其他非HCV感染患血清,从3种EIA试剂同时阴性或阳性的血样中挑取阳性和阴性血清,然后用RNA hyb PCR试剂进行检测,从中再选取部分样本用RIBA3．0进行检测,确定HCV分片段抗体检测蛋白质芯片质控参比品。经质检合格的芯片用中国药品生物制品检定所的HCV参比品进行检定。通过490例临床标本的检测对芯片的质量进行进一步的验证。从收集的240份丙型肝炎病毒感染患血清及其他非HCV感染患血清筛选出30份血样(15份阳性,15份阴性)作为HCV分片段抗体检测蛋白芯片质控参比品。中国药品生物制品检定所的80份HCV参比品检定结果表明,混合抗体阳性检出率为39／40,阴性符合率为40／40,总符合率为98．7％;核心抗体阳性检出率为27／40,阴性符合率为40／40;NS3抗体阳性检出率为26／40,阴性符合率为39／40;NS4抗体阳性检出率为19／40,阴性符合率为40／40;NS5抗体阳性检出率2／40,阴性符合率为40／40。490例临床标本的检测结果表明,对于194例HCV阳性标本,蛋白质芯片混合抗体与ELISA的符合率达99．5％,分片段抗体符合率达97．4％,两种方法检测结果不符的标本经RIBA试剂确认,蛋白质芯片与RIBA试剂的符合率高度一致。对于296例各种HCV抗体阴性标本,蛋白质芯片检测结果全部为阴性。以上结果表明,制备的丙型肝炎病毒分片段抗体检测蛋白质芯片质控参比品可用于芯片生产的质量控制,经质控合格的芯片符合国家标准的要求,可用于临床检测。     

Improved quality management to enhance the efficacy of the sterile insect technique for lepidopteran pests

Lepidoptera are among the most severe pests of food and fibre crops in the world and are mainly controlled using broad spectrum insecticides. This does not lead to environmentally sustainable control and farmers are demanding alternative control tools which are both effective and friendly to the environment. The sterile insect technique (SIT), within an area‐wide integrated pest management (AW‐IPM) approach, has proven to be a powerful control tactic for the creation of pest‐free areas or areas of low pest prevalence. Improving the quality of laboratory‐reared moths would increase the efficacy of released sterile moths applied in AW‐IPM programmes that integrate the (SIT). Factors that might affect the quality and field performance of released sterile moths are identified and characterized in this study. Some tools and methods to measure, predict and enhance moth quality are described such as tests for moth quality, female moth trapping systems, ‘smart’ traps, machine vision for recording behaviour, marking techniques, and release technologies. Methods of enhancing rearing systems are discussed with a view to selecting and preserving useful genetic traits that improve field performance.     

Effect of salinity on physiological characteristics,yield and quality of microtubers <Emphasis Type="Italic">in vitro</Emphasis> in potato

In vitro microtuberization provides an adequate experimental model for the physiological and metabolic studies of tuberization and the preliminary screenings of potential potato genotypes. The effects of saline stress at 0–80 mmol concentration on in vitro tuberization of two potato cultivars were investigated in this study. With an increase in the salt concentration, the microtuberization of potato was either delayed by 5–10 days (20 and 40 mmol NaCl) or inhibited completely (80 mmol NaCl) in addition to the reduction in microtuber yields. The two potato genotypes studied showed different trends in total soluble sugars, sucrose and starch contents of microtubers under NaCl stress, while glucose and fructose levels remained unchanged. The vitamin C content in microtubers of two potato genotypes was reduced by salt stress. Salinity applied from 20 to 60 mmol progressively increased proline and malondialdehyde (MDA) levels in microtubers of both the potato cultivars. In genotype Zihuabai, NaCl at a low concentration (20 mmol) led to a significant increase in peroxidase (POD) and polyphenoloxiadase (PPO) activities, while in Jingshi-2, the PPO activity decreased progressively with an increase in NaCl concentrations. Genotype Zihuabai exhibited higher tolerance to salt stress than Jingshi-2 under in vitro conditions. These results could be used for preliminary selections of salt tolerance in potato breeding programmes.     

Genetic and substrate-level modulation of Bacillus subtilis physiology for enhanced extracellular human interferon gamma production

Human interferon-gamma (hIFNG) production is limited by various gene-level bottlenecks including translation, protein folding, and secretion which depends upon the physiological state of the organism. In this study gene-level and substrate-level modulations have been used to control Bacillus subtilis physiology for >15 fold extracellular soluble hIFNG production. Two variants of the native human interferon-gamma gene (hifng) were designed and synthesized, namely, cohifng_his and cohifng having codon adaptation index 25.33 and 26.89% higher than the native gene, respectively. BScoIFNG and BScoIFNGhis with ΔG of ?100.0 and ?113.7?kcal?mol^?1 resulted in 30 and 6.5% higher hIFNG compared to the native gene in complex medium. BScoIFNG produced 1.53 fold higher hIFNG using glucose-based defined medium as compared to the complex medium by modulating the physiological parameter growth rate from 0.35 to 0.26?hr^?1. Further modulatory effect of various phosphotransferase transport system (PTS) and no-PTS sugars, sugar alcohols, and organic acids was quantified on the physiology of B. subtilis WB800N for extracellular hIFNG production. Sorbitol and glycerol emerged as the best hIFNG producers with lowest growth and substrate consumption rates. BScoIFNG produced maximum 3.15?mg?L^?1 hIFNG at 50?g?L^?1 glycerol with highest hIFNG yield (Y_p/x?=?0.136) and lowest substrate uptake rate (q_s?=?0.26).     

Adjuvant gamma knife surgery and image-guided,intensity-modulated radiation therapy for the treatment of sacral chordomas

AimThe aim of this study was to confirm whether patients with sacral chordoma benefit from adjuvant radiotherapy and to determine the optimal photon radiotherapy module for comprehensive treatment.BackgroundChordoma is a rare slow-growing neoplasm arisen from cellular remnants of the notochord. About 50% occur in the sacrococcygeal region. Surgical resection and adjuvant radiation therapy are recommended treatment due to the improving local control rate.Materials and methods118 patients treated by surgery and adjuvant radiotherapy from August 2003 to May 2015 were retrospectively analyzed. All patients received surgical resection after diagnosis. Among these patients, 44 were treated by exclusive surgery, and 48 were treated with adjuvant image-guided, intensity-modulated radiation therapy (IG-IMRT). In addition, 26 patients were treated with gamma knife surgery (GKS) after surgical resection. The median follow-up was 54 months for all patients. Kaplan–Meier analysis was used to calculate recurrence-free survival (RFS) overall survival (OS).ResultsPatients treated with adjuvant radiotherapy had better RFS (p = 0.014) than those treated exclusively by surgery. The patients in the IG-IMRT group exhibited better recurrence-free survival (p = 0.01) than the GKS group. Moreover, in the IG-IMRT group, patients treated by higher dose were associated with better RFS (p = 0.04). No significant difference in OS was found. No grade 3 late toxicity was found.ConclusionsWe confirmed that adjuvant radiotherapy improved RFS but not OS in sacral chordoma patients after surgery. Furthermore, favorable RFS and low adverse event rates were observed following IG-IMRT. Our results suggest that high dose IG-IMRT is an appropriate module of adjuvant radiotherapy for sacral chordoma patients.     

Elevated UV-B radiation has no effect on litter quality and decomposition of two dune grassland species: evidence from a long-term field experiment

From studies on living plant tissues it has been inferred that elevated UV‐B radiation could negatively affect litter quality and subsequent decomposition. However, in general, the effects of UV‐B radiation on litter chemistry and decomposition reported in the literature are variable and are often only marginally (if at all) significant. This might be due to the ecologically unrealistic conditions under which these experiments were performed. We investigated the effects of elevated UV‐B radiation on litter quality and subsequent decomposition on initial litter chemistry and long‐term (2 years) decomposition of freshly senesced Carex arenaria and Calamagrostis epigejos leaf litter under ecologically realistic conditions. This material was collected from a dune grassland that had received UV‐B radiation treatments for three growing seasons. It was then used in a 2‐year decomposition study using litter bags. We found no significant effects of elevated UV‐B radiation on any of the litter chemistry parameters in either of the two species, nor did we find significant effects on litter decomposition. However, we did find significant differences in litter decomposition between the species. These differences were related to the interspecific differences in litter chemistry, particularly the litter phenolics concentration. These results show that litter quality and decomposition in dune grasslands are, also under ecologically realistic conditions, not affected by UV‐B radiation. Instead, litter decomposition is determined by constitutive interspecific differences in litter chemistry. In conclusion, with our results added to the already existing literature, the preponderance of evidence now clearly suggests that elevated UV‐B radiation has very little, if any, impact on litter quality and subsequent decomposition in real ecosystems.     

Modification and Application of a Leaf Blower-vac for Field Sampling of Arthropods

Rice fields host a large diversity of arthropods, but investigating their population dynamics and interactions is challenging. Here we describe the modification and application of a leaf blower-vac for suction sampling of arthropod populations in rice. When used in combination with an enclosure, application of this sampling device provides absolute estimates of the populations of arthropods as numbers per standardized sampling area. The sampling efficiency depends critically on the sampling duration. In a mature rice crop, a two-minute sampling in an enclosure of 0.13 m² yields more than 90% of the arthropod population. The device also allows sampling of arthropods dwelling on the water surface or the soil in rice paddies, but it is not suitable for sampling fast flying insects, such as predatory Odonata or larger hymenopterous parasitoids. The modified blower-vac is simple to construct, and cheaper and easier to handle than traditional suction sampling devices, such as D-vac. The low cost makes the modified blower-vac also accessible to researchers in developing countries.     

Radical scavenging and chemical repair of rutin observed by pulse radiolysis: as a basis for radiation protection

Abstract

Pulse radiolysis was conducted to investigate: several fundamental reactions of a natural flavonoid, rutin, and its glycosylated form (αG-rutin) as a basis for their radiation protection properties; the reactions with ^?OH (radical scavenging) and dGMP radical, dGMP^? (chemical repair), which was used as a model of initial and not yet stabilised damage on DNA. Three absorption peaks were commonly seen in the reactions of the flavonoids with ^?OH, showing that their reactive site is the common structure, i.e. aglycone. One among the three peaks was attributed to the flavonoid radical produced as a result of the removal of a hydrogen atom. The same peak was found in their reactions with dGMP^?, showing that dGMP^? is chemically repaired by obtaining a hydrogen atom supplied from the flavonoids. Such a spectral change due to the chemical repair was as clear as never reported. The rate constants of the chemical repair reaction were estimated as (9?±?2)×10⁸ M^?1 s^?1 and (6?±?1)×10⁸ M^?1 s^?1 for rutin and αG-rutin, respectively. The rate constants of the radical scavenging reactions towards ^?OH were estimated as (1.3?±?0.3)×10¹⁰ M^?1 s^?1 and (1.0?±?0.1)×10¹⁰ M^?1 s^?1 for rutin and αG-rutin, respectively. In addition, there was no obvious difference between rutin and αG-rutin, indicating that the glycosylation does not change early chemical reactions of rutin.     

Application of PSX biocontrol preparation confers root-knot nematode management and increased fruit quality in tomato under field conditions

PSX is a combination of biocontrol bacteria that can potentially prevent and control soil-borne diseases for a variety of crop cultivars. In this study, we investigated the utility of PSX in controlling root-knot nematodes in tomato under field conditions. The application of PSX reduced the severity of disease caused from Meloidogyne incognita by 63–69% and increased tomato yield by 31.5–39%. Furthermore, to investigate the effect of PSX treatment on tomato fruit quality, we quantified the soluble sugar, titratable acid, soluble solids, and vitamin C contents in fruit postharvest. We demonstrated that PSX treatment improved tomato fruit quality. Finally, we also showed that the total nitrogen (N), available N, potassium, and organic matter contents in the soil increased after PSX treatment. PSX is a promising biocontrol preparation that can provide beneficial effects to tomato growers, including biological control of root-knot disease, plant growth promotion, enhanced tomato fruit quality, and increased levels of organic fertilisers in the soil.     

Evaluation of iophenoxic acid and rhodamine B for marking feral ferrets (Mustela furo)

Abstract

The blood marker iophenoxic acid, and the fluorescent dye rhodamine B, were evaluated as means of assessing bait consumption in the ferret, Mustela furo. Iophenoxic acid was elevated above baseline concentrations for a minimum of 28 days after dosing, indicating that it is a suitable medium‐term marker. Rhodamine B marked ferrets for a maximum of 7 days, and would therefore have limited operational use with feral ferrets. Iophenoxic acid was used in a field trial to assess the effectiveness of a newly developed baiting strategy for control of wild ferrets. All 21 ferrets captured after field baiting with iophenoxic acid had elevated levels of serum iodine, indicating that the newly developed baiting strategy is highly effective for marking ferrets.     

肺炎链球菌荚膜多糖特异性IgG抗体定量ELISA检测及质量控制要求

检测肺炎链球菌荚膜多糖(PPS)特异性抗体的酶联免疫吸附试验多年来经历了两次主要改进。介绍了WHO推荐的人血清抗肺炎链球菌(Streptococcus pneumoniae)荚膜多糖抗体IgG定量ELISA(Pn PS ELISA)检测方法、关键试剂、局限性以及方法验证等内容。ELISA定量检测法,为预防肺炎链球菌的婴幼儿侵袭性疾病提供准确的抗体水平,并对肺炎链球菌疫苗的临床评价提供血清学证据。人血清中肺炎链球菌荚膜多糖抗体IgG是判断肺炎链球菌疫苗效力的重要指标。