Correction:Jetting-based bioprinting:process,dispense physics,and applications

The article Jetting-based bioprinting:process,dispense physics,and applications,written by Wei Long Ng and Viktor Shkolnikov,was originally published electronically on the publisher’s internet portal on 12 July 2024 without open access.

Establishment of Alloptilella splendida gen.et sp.nov.and resurrection of Scytalium veneris(Thomson&Henderson,1906),two sea pens(Cnidaria:Pennatulacea)from seamounts in the tropical Western Pacific

Sea pens are a highly specialized and morphologically distinct group of octocorallians,but many taxa were poorly described and their phylogenetic relationships are still poorly known.We describe two species of sea pens collected from the tropical Western Pacific:Alloptilella splendida gen.et sp.nov.and Scytalium veneris(Thomson&Henderson,1906).Alloptilella splendida gen.et sp.nov.accords with the definition of the recently resurrected genus Ptilella Gray,1870 in most characters,but differs from the latter in the arrangement of autozooids and the location of mesozooids.The new species mostly resembles Pennatula naresi K(o|")lliker(1880),but differs by the location of me sozooids and the reddish color of sclerite s surrounding siphonozooids.The generic separation is also well supported by their genetic distances and the molecular phylogenetic trees constructed by the concatenated mtMutS-COI-28 S,where Alloptilella clustered with Scytalium Herklots,1858 and formed a clade with the cluster of Ptilella and Distichoptilum.Scytalium veneris,usually considered as a junior synonym of Scytalium sarsii Herklots,1858,is resurrected by recognizing their distinctive differences.This is the first record of Scytalium veneris outside its type locality,and the phylogenetic analysis indicates that Scytalium is a monophyletic group.Both the families Pennatulidae and Virgulariidae are polyphyletic,and more morphological and molecular data are needed to clarify the phylogenetic positions of pennatulacean families and genera.

高阻隔性复合PEN/PET饮料包装瓶的制备及阻隔性能研究

PET瓶是当前市场上广泛应用的饮料包装瓶之一,但随着消费者对饮料品质要求的提升,对饮料包装瓶的气体阻隔性有了更高的要求。为了改进纯聚对苯二甲酸乙二醇酯(PET)瓶的阻隔性,本实验利用熔融共混的方法制备PEN/PET复合材料,在确定共混材料的最佳配比后,加工制得复合聚萘二甲酸乙二醇酯/聚对苯二甲酸乙二醇酯(PEN/PET)饮料包装瓶,并通过测定氧气、二氧化碳和水蒸气的透过量,以及紫外阻隔性能、光学性能、机械性能和耐热性能,对其进行阻隔性能分析。通过综合分析比较,确定PEN30%wt、PET70%wt为最佳配比。制得的复合PEN/PET饮料包装瓶与普通PET瓶相比,氧气阻隔性增加3.48倍,二氧化碳阻隔性增加7.36倍,水蒸气阻隔性增加2.25倍,除此之外,其紫外线阻隔性等性能也有显著提高。在常温下贮藏70d后,复合PEN/PET瓶对饮料的保存效果明显优于纯PET瓶。复合PEN/PET饮料包装瓶改进了纯PET瓶的阻隔性较弱的问题。

伴随中子管Penning源诊断及仿真研究

Penning离子源因为结构简单、体积小、功耗低等优点,被广泛应用在伴随中子管中。基于实验室所用的潘宁(Penning)离子源,分析其电离时的伏-安特性;通过CCD相机拍摄观察离子源内部等离子体分布情况;采用光谱法诊断氢等离子体中电子的密度和温度。基于实验测试用的Penning离子源结构,建立H2分子碰撞电离的全局模型,分析离子源的工作参数与等离子体中电子温度和电子密度之间的关系。仿真结果表明:电子温度和电子密度与离子源的运行压强、磁场和功率密切相关;电子密度随功率增加逐渐增加、随磁场强度和压强都是先增加后减小,因此需将磁场强度控制在0.03~0.05 T,压强控制在(0.2~2)×10^(-2)Pa之间;电子温度随功率增加逐渐增加、随压强增加逐渐减小。通过模型可知,在Penning离子源的工作区间内,电子平均温度小于10 eV,电子密度数量级为10^(10) cm^(-3)。

Food Selection of Apodemus peninsulae under Artificial Rearing Condition

[ Objective ] The paper aimed to screen the poison bait and lure suitable for controlling Apodemus peninsulae. [ Method ] A. peninsulae was reared individually in a single cage, to observe its feeding conditions. [Result] A. peninsulae preferred carrot and cucumber, followed by peanut, and rat diet was the last choice. [ Conclusion] Carrot and cucumber could be used to prepare poisoning bait for controlling A. peninsulae, in order to improve rat capture efficiency.

Study of the Compensatory Growth Following Starvation of Juvenile Golden Pompano Trachinotus ovatus

A starvation trial was conducted to determine compensatory growth of the juvenile golden pompano Trachinotus ovatus which were deprived of food for 1, 2, 5 and 7 days respectively. The results of tests in outdoor cement pools and net pens showed that, in the first 15 days and 30 days, the growth of 1 day and 2 days-deprived groups was probably the same with that of control group, which accorded with fully compensatory description. However, the weight of 5 days and 7 days-deprived fingerlings were lower than that of the control group, which accorded with the description of the partial compensatory growth. As the starvation prolonged, feed conversion efficiency of the starved groups increased and was higher than the control group. Meanwhile, feeding rate also increased, but the fish of 1 day and 2 days-deprived groups was lower than that of the control group, and feeding quantity reduced and was lower than that of the control group. It suggested that the mechanism of compensatory growth was mainly due to improving feed conversion efficiency. Fish biochemical composition was analyzed： the water content and ash of fish sample increased due to starvation, while the lipid and protein decreased. The loss of lipid was greater than that of the protein, and the biochemical composition of fish in each group was restored to the control level by the end of the experiment. It suggested that Trachinotus ovatus may mainly consume lipid during the period of starvation.

Gut Peculiarities of Feed Deprived White Sturgeons (<i>Acipenser transmontanus</i>, Richardson 1836)

In the White sturgeon fish farms, some individuals have difficulty in getting access to food: such sturgeons are called "runts", and they result in a slower growth rate than normally feeding fish. In this paper, we have studied the gut peculiarities of runt sturgeons. Utilizing in paralleling an analysis of diatom populations in both the fish gut tissues and the rearing tank waters, we hypothesized a causative relation between the occurrence of runt sturgeons and periodic diatom blooms. In fact, we have observed that the diatom species identified in the aquatic environment were also detected in organs (Fragilaria spp and Rhoicosfenia spp for both glandular body, mid-intestine) of the runt sturgeon's gut, but not in tissues of normally feeding individuals. Owing to their siliceous wall, diatoms can be responsible for areas of epithetlial detachment in the mucosal surfaces of the alimentary canal and a catharral inflammation in both the gastric pits and intestinal folds which may be the cause of secondary bacterial diseases. We suggest that diatom blooms may contribute to the occurrence of runt sturgeons in the studied Italian fish farm.

Inappropriate antibiotic dispensing and use:A public health threat in the Philippines

A high rate of improper antibiotic dispensing was reported to patients with presumed viral infections even without a prescription from a physician in Vietnam[1]. Imprudent antibiotic dispensing and use were also observed in other countries, including the Philippines. A large number of patients experienced respiratory symptoms, such as cough and rhinorrhea during the COVID-19 pandemic, which exacerbated this problem with antibiotic use.

Synthesis of Water-Soluble Chitosan From Squid Pens Waste for Capsule Shell Materials

Water-Soluble Chitosan(WSC)has been sucessfuly synthesized from squid pens waste.The synthesis of chitosan from chitin was carried out by optimization of deacetylation temperature and time.Chitin was obtained from squid pens waste by demineralization and deproteinization process.HCl 7%was used for demineralization and NaOH 10%at 60℃ was applied for deproteinization process.Deacetylation reaction was carried out at varied temperatures i.e.,60℃,70℃,80℃,90℃ and 100℃ in NaOH 50%solution for 10 hours.Deacetylation reaction time were varied for 2 hours,4 hours,6 hours,8 hours,and 10 hours.The crude chitosan obtained then reacted with H2O230%to depolymerize.The synthesis product obtained then characterized by FTIR.The result of squid chitin yield was 33.9%.The optimum temperature and time of chitosan deacetylation process were 90℃ for 8 hours as indicated by the value of deacetylation degree(DD)that equal to 83.94%at optimum temperature and 82.22%at optimum reaction time.The percentage of WSC yield at optimum temperature(90℃)and optimum time(8 hours)were 27.59%and 23.16%,respectively.WSC solubility test was done in water and HCl 0,1N.The solubility of 2.8325 mg/mL and 0.8125 mg/mL were obtained in acid medium and water medium,respectively.

PEN纤维帘线浸胶过程中聚集态结构演变和力学性能研究

探讨PEN纤维帘线浸胶过程中聚集态结构演变和力学性能。通过对浸胶整理过程中的干燥一区、拉伸区、干燥二区和定形区这4个区域的样品进行研究,分析了PEN纤维帘线在浸胶后整理过程中聚集态结构、热性能、取向参数、力学性能的演变。结果表明:PEN纤维帘线在浸胶过程中结晶度由67.85%逐渐增加到69.45%;晶面的晶粒尺寸均略微增大;DSC熔融峰逐渐尖锐,结晶度增加,表明分子链聚集态结构趋于稳定和完善。PEN纤维帘线在热定形处理时纤维非晶区大分子链的取向度无明显下降,帘线的热收缩降为1.50%,有利于提高纤维帘线的热稳定性。动态和静态力学性能表明,PEN纤维帘线的断裂强度和模量未出现明显变化。

The Quality of Chinese Pens Upgraded

During the Eighth Five-Year Plan period, (1991-95), China’s pen industry maintained sustained, rapid, stable and sound development with the further promotion of product quality and grade in production, and its technological advancement. At the same time, new varieties of products and more patterns and specifications were developed. The industry also further developed its business ties with clients abroad and ex-

Rearing the Predator Brontocoris tabidus(Heteroptera:Pentatomidae)with Tenebrio molitor(Coleoptera:Tenebrionidae)Pupa on Eucalyptus grandis in the Field

The use of natural enemies represents an important strategy in programs of Integrated Pest Management (IPM). Asopinae predators are reared with alternative prey, but supplementary plant may enhance the fecundity and longevity of their females. The objective of this research was to evaluate the development and reproduction of the predator Brontocoris tabidus Signoret, 1852 (Heteroptera: Pentatomidae) fed with Tenebrio molitor L., 1785 (Coleoptera: Tenebrionidae) pupae in a Eucalyptus grandis Hill ex Maiden (Myrtaceae) plant in the field. The duration and survival of the nymphal stage of B. tabidus were 32.07 ± 8.95 days and 77.00 ± 0.42%, respectively with 15.55 ± 8.19 egg masses, 603.00 ± 379.20 eggs and 387.45 ± 291.40 nymphs per female of this predator while longevity of its males and females was 119.80 ± 32.80 and 160.20 ± 42.13 days, respectively. Better results with E. grandis plant in the field and the fact that B. tabidus will be adapted at release time show that this predator should be reared in these conditions.

Study on damage mechanism and damage distribution of the rear plate under impact of debris cloud

The debris cloud generated by the hypervelocity impact(HVI)of orbiting space debris directly threatens the spacecraft.A full understanding of the damage mechanism of rear plate is useful for the optimal design of protective structures.In this study,the hypervelocity yaw impact of a cylindrical aluminum projectile on a double-layer aluminum plate is simulated by the FE-SPH adaptive method,and the damage process of the rear plate under the impact of the debris cloud is analyzed based on the debris cloud structure.The damage process can be divided into the main impact stage of the debris cloud and the structural response of the rear plate.The main impact stage lasts a short time and is the basis of the rear plate damage.In the stage of structure response,the continuous deformation and inertial motion of the rear plate dominate the perforation of the rear plate.We further analyze the damage mechanism and damage distribution characteristics of the rear plate in detail.Moreover,the connection between velocity space and position space of the debris cloud is established,which promotes the general analysis of the damage law of debris cloud.Based on the relationship,the features of typical damage areas are identified by the localized fine analysis.Both the cumulative effect and structural response cause the perforation of rear plate;in the non-perforated area,cratering by the impact of hazardous fragments is the main damage mode of the rear plate.

PET/PEN/DBS共混物非等温结晶动力学研究

采用DSC方法，用修正的Avrami，Ozawa，Ziabicki宏观动力学模型描述PET／PEN／DBS[PFT：聚对苯二甲酸乙二醇酯；PEN：聚2，6-萘二甲酸乙二醇酯；DBS：1，3：2，4-二（亚苄基）-D山梨醇]共混物的非等温熔融结晶过程，研究结果表明，修正的Avrami模型能很好地描述此共混物非等温结晶过程．冷却速率在5～20℃／min范围内，Ozawa方程能很好地描述初期结晶过程，但结晶后期由于忽略次级结晶而不适宜．由Ziabicki结晶动力学参数可知，该共混物的结晶随着成核剂DBS含量的增加而降低，结晶速率随着成核剂DBS含量的增加而提高．在非等温结晶条件下，共混物结晶同时受到冷却速率和共混物组成的影响，与共混物非等温结晶过程的有效能垒分析结果基本一致．

PET/PEN共混物的相容性与酯交换反应

通过用1H-NMR对聚对苯二甲酸乙二酯(PET)与聚2,6-萘甲酸乙二酯(PEN)、PET/PEN共聚物的共混物酯交换反应的研究,测得了反应速率常数、反应活化能和诱导期.根据酯交换反应程度和不同反应温度下的诱导期探讨了酯交换反应与相容性的关系,认为PET与PEN的相容导致或增强了酯交换反应,即相容性是酯交换的必要条件;同时酯交换的发生又促进了PET与PEN的相容.酯交换和相容是聚酯共混物熔融时相互关联的两个过程.

PET/PEN扩链反应共混的研究 Ⅰ.共混条件对酯交换及链结构的影响

用 1H- NMR方法对 PET/ PEN在少量扩链剂存在下的反应性共混条件对酯交换反应及序列结构的影响作了系统研究。结果表明 ,混合时间、温度对酯交换反应有显著的影响。随着时间的增加和温度的提高酯交换程度增加 ,而导致共聚酯的数均序列长度变短。共混物的组成及少量扩链剂的存在 ,在某些条件下对酯交换反应及序列结构也显现出较明显的影响。

PET/PEN共混体系结构与性能研究进展

综述了国内外PET/PEN共混体系的研究进展,重点论述了PET/PEN共混体系的结晶性能相容性酯交换影响因素、结晶动力学,并对其应用前景做了展望。

模拟胃液对Pen a 1及其抗原表位免疫原性的影响

【目的】Pen a 1是虾中的主要过敏原,已知其5个抗原表位在过敏反应中起着决定性的作用。用全蛋白抗体和表位特异性抗体,检测Pen a 1经体外模拟胃液(simulated gastric fluid,SGF)消化后其抗原表位免疫原性的变化情况,为研究人体消化对Pen a 1的影响机理及脱敏食品的制备提供理论依据。【方法】以刀额新对虾(metapenaeus ensis)为原材料,提取纯化虾过敏原Pen a 1,采用Fmoc化学法合成Pen a 1抗原表位的5个多肽片段(No.1—No.5),分别与载体蛋白KLH和牛血清蛋白BSA偶联制备人工免疫原和包被原。用Pen a 1和制备的多肽免疫原免疫新西兰纯种白兔获得全白蛋抗体和特异性表位抗体。参照美国药典模拟人体胃液的条件消化处理Pen a 1,利用SDS-PAGE和Tricine-SDS-PAGE观察消化后Pen a 1分子量变化;通过免疫印迹(Western-blot)定性观察Pen a 1消化后生成的新蛋白片段与各抗体的结合情况;再经竞争抑制酶联免疫吸附试验(ci-ELISA)定量检测消化后的Pen a 1和表位多肽与各抗体结合能力,从而得出Pen a 1经SGF消化后各抗原表位免疫原性的变化程度。【结果】SDS-PAGE结果显示Pen a 1随SGF消化时间的延长逐渐被降解,在22 kD处生成一些较稳定的新蛋白片段,Tricine-SDS-PAGE结果表明在1.7—18 k D之间无新蛋白片段生成。Western-blot表明消化后分解生成的小分子蛋白与六种抗体发生不同程度结合,其中全蛋白抗体和No.4抗体几乎与生成的所有小分子蛋白结合,在22 k D左右处生成的稳定新蛋白片段均与No.3、4、5抗体有较强的结合,而与No.1、2抗体结合较弱甚至无结合,表明该蛋白携带No.3、4、5表位,而基本无No.1、2表位。ci-ELISA结果显示,Pen a 1经SGF消化后对全蛋白抗体和5个表位抗体的抑制率均显著下降,说明经过消化后Pena1及其抗原表位的免疫原性均明显降低,各抗原表位消化稳定性排序为No.4>No.2>No.1>No.3>No.5,其中No.2、1、3之间无显著性差异;ci-ELISA检测表位多肽经消化后其免疫原性也显著下降,消化稳定性排序为No.1>No.2>No.3>No.4>No.5,其中No.2、3、4之间无显著性差异。结合免疫印迹结果可知No.4抗原表位消化稳定性最高,但其表位多肽消化稳定性没有显著高于其它所有表位多肽,说明在消化过程中Pen a 1结构对该表位起到一定的保护作用,使其保持较高的消化稳定性;No.1、2、3次之,3个表位间无显著性差异;No.5消化稳定性最差,表明Pen a 1空间结构对其无明显保护作用。【结论】建立了一种用表位抗体检测过敏原经模拟消化后抗原表位消化稳定性的方法。Pen a 1经SGF消化后,免疫原性降低,分解生成部分较稳定的蛋白片段,但仍具有致敏性;5个抗原表位中No.4消化稳定最高,No.5最差。

PEN和PET的流变性能

聚2,6-萘二甲酸乙二醇酯(PEN)是一种结构上与PET非常相近的新型聚酯,近年来逐渐成为研究的热点。利用哈克流变仪对PET和PEN在不同温度及剪切速率下的流变性能进行了研究。流变行为研究表明:PEN的剪切黏度随剪切速度的增加而减小,属于典型的非牛顿流体;从流变曲线上来看,随着剪切速率的改变,PEN的剪切黏度的变化要小;而黏流活化能则表明:PEN剪切黏度的变化对温度的变化更敏感,这就意味着PEN对加工工艺具有更高的要求。

新型高效包装用高分子材料——聚萘二甲酸乙二醇酯(PEN)

论述了聚萘二甲酸乙二醇酯（ＰＥＮ）的研究现状，合成方法，性能及ＰＥＮ／ＰＥＴ共混物（或共聚物）的有关情况。