Structural and Co-conformational Effects of Alkyne-Derived Subunits in Charged Donor−Acceptor [2]Catenanes

Four donor−acceptor [2]catenanes with cyclobis(paraquat-p-phenylene) (CBPQT^(4+)) as the π-electron-accepting cyclophane and 1,5-dioxynaphthalene (DNP)-containing macrocyclic polyethers as π-electron donor rings have been synthesized under mild conditions, employing Cu^+-catalyzed Huisgen 1,3-dipolar cycloaddition and Cu^(2+)-mediated Eglinton coupling in the final steps of their syntheses. Oligoether chains carrying terminal alkynes or azides were used as the key structural features in template-directed cyclizations of [2]pseudorotaxanes to give the [2]catenanes. Both reactions proceed well with precursors of appropriate oligoether chain lengths but fail when there are only three oxygen atoms in the oligoether chains between the DNP units and the reactive functional groups. The solid-state structures of the donor−acceptor [2]catenanes confirm their mechanically interlocked nature, stabilized by [π···π], [C−H···π], and [C−H···Ο] interactions, and point to secondary noncovalent contacts between 1,3-butadiyne and 1,2,3-triazole subunits and one of the bipyridinum units of the CBPQT^(4+) ring. These contacts are characterized by the roughly parallel orientation of the inner bipyridinium ring system and the 1,2,3-triazole and 1,3-butadiyne units, as well as by the short [π···π] distances of 3.50 and 3.60 Å, respectively. Variable-temperature ^1H NMR spectroscopy has been used to identify and quantify the barriers to the conformationally and co-conformationally dynamic processes. The former include the rotations of the phenylene and the bipyridinium ring systems around their substituent axes, whereas the latter are confined to the circumrotation of the CBPQT^(4+) ring around the DNP binding site. The barriers for the three processes were found to be successively 14.4, 14.5−17.5, and 13.1−15.8 kcal mol^(-1). Within the limitations of the small dataset investigated, emergent trends in the barrier heights can be recognized:  the values decrease with the increasing size of the π-electron-donating macrocycle and tend to be lower in the sterically less encumbered series of [2]catenanes containing the 1,3-butadiyne moiety

On the Production of Severely Deformed Workpieces in Large Scales: A Step Towards Industrialization

© 2019, The Author(s). Improvement of the functional properties of aluminium and its alloys by grain refinement is an effective way to increase their applications. The capability of severe plastic deformation methods to produce ultrafine-grained materials has been well established. However, their industrial application is limited because of the required additional equipment and limitation of the product size. Due to the direct extrusion characteristic of the simple shear extrusion (SSE) method and consequently the minimal additional tools and expenses, SSE is a good candidate for commercialization. The aim of this research is to scale up the SSE products to facilitate their potential use in practical applications. To overcome the limitation on the length of the plunger and reduce the load of the SSE process, a design is proposed in the current research. Microstructural investigations and mechanical tests of commercial pure aluminium (AA1050) workpieces confirm the effectiveness of the proposed design on the grain refinement and its capability to reduce the processing load

Evaluation of the immunity factors (THC, TPP, PO, SOD, POD) of shrimp fed with the algae Gracilaria corticata compared to shrimp fed without algae and exposed to white spot virus

White spot disease (WSD) is one of the shrimp deadliest viral diseases that causes heavy losses on all shrimp of Penaeid family. Most invertebrates are lacking adaptive immune system and its defense is the innate immune system that is as cellular and humoral, but a like immune system against white spot virus in shrimp was been detected. In this research, control and prevention of white spot disease in shrimp using algae Gracilaria corticata, investigated. About 300 vannamei shrimp were divided to 4 groups and fed by normal pellet and algae extract in 14 days. At the end of the fourteenth day half of the shrimp were challenged with acute white spot virus. After the fourteenth day in the days 0, 3, 9, 18 and 25 sampling were done from the hemolymph of survived shrimps and survival and immune factors were evaluated. Based on results, in the challenge test, shrimps that fed with algae extract has a significant survival rate than shrimp fed with commercial diet. Increased the Immune Factors from day one to day 25 observed during the test. Greatest amount of Immune Factors THC, TPP, SOD, POD and PO in T1 group were observed in day 25 of tests. This situation was also true for group2 (T2), but its rate significantly was less than group 1(T1)

The survey and identification source of white spot disease in shrimp Farm in Abadan area

In the summer of 2002 high mortality occurred in farm shrimp in Abadan area due to white spot disease. The main objective of this study was detection and identification the source of white spot syndrome virus. For this reason from 2004/11/4 until 2005/120/6 about 190 samples consisted of wild shrimp, crab, fish, and plankton collected and preserved in alcohol 90-75% for polymerase chain reaction (PCR).The samples transferred to the South Iranian Aquaculture Center in Ahwaz. The samples examined by commercial WSSV detection kit (Fast Target) and new kit design by Iranian Fisheries Research Organization (IFRO) and Biotechnology Research Center from Iran. The result from PCR showed the samples of Penaeus indicus brood stock and postlarvea, Parapenaeopsis stylifrus and Metapenaeus affinis was positive. The rest of samples did not show any sign of virus and they was negative by PCR. Because the disease outbreak occurred in 2002 and the samples collected in 2004, the situation of environmental in the area was changed and may be the virus disappears in the samples and died

Growth and survival rates, mean weight, food conversion ratio and total harvest in cultured Shrimp Litopenaeus vannamei in Iran

To introduce Litopenaeus vannamei to Iran as a cultured shrimp species, a experimental study was carried out to assess the effects of different stocking densities on growth rate, mean weight, survival rate, food conversion ratio and the total harvest of L. vannamei. Mee post-larval groups (P1,12) of L. vannamei (pond A: 20 PL/m2, pond B: 30 PL/m2 and pond C: 50 PL/m2) with average size 0.9cm and initial mean weight 0.01±0.005g were used in this study. The experiments were carried out in three replications in 9 earthen ponds each half a hectare in size in Khouzestan province, south of Iran during 110 days. The result showed there was no significant correlation (P>0.05) between stocking density and survival rate in the semi intensive culture condition. Mean survival rate among farms were greatest at the lowest density, where mean survival in pond A, B, and C was 88.6%, 83.3%, 73.3%, respectively but the differences were not significant (P>0.05). The results also showed there was no significant relationship (P>0.05) between growth rate and growth days in each experiment. The mean growth rate/days for ponds A, B, and C were calculated at 0.16g/day, 0.16g/day and 0.15g/day, respectively. The food conversion ratio in the end of the study period for ponds A, B and C was 1.01, 1.17 and 1.2, respectively. Shrimp production increased with an increase in stocking density when farm production at Pond A and B indicated a significant difference (P<0.05) compared to that of the pond C. The total shrimp production for ponds A, B and C was calculated at 2803kg/ha, 3146kg/ha and 3972kg/ha, respectively. The water temperature ranged between 28±3°C to 23±3°C, with the highest in July and lowest in September. Salinity ranged between 25±2ppt to 12±3ppt, pH ranged between 8.6±0.2 to 7.50.4 and dissolved oxygen ranged between 5.8± 0.4ppm to 5.3±0.3ppm throughout the study. The study proved that L. vannamei could adapt to common conditions in Iranian shrimp culture environment and also we showed that the species production was higher than the native species already under culture

A study on immunological factors in white spot vaccinated shrimp, Litopenaeus vannamei in comparison to none vaccinated groups

The aim of this study was to evaluate the efficacy of white spot virus vaccine produced by gamma irradiation in the face of Litopenaeus vannamei in comparison with Gracilaria corticata and Saccharomyces cerevisiae Seven hundred and twenty healthy shrimp SPF L. vannamei subadult with average weight of 10±1.02 g were collected and divided into 8 groups. The first group (T1) was fed with commercial pellet as control. The second group (T2) was fed with S. cerevisiae added to shrimp feed (1 g/Kg), the third group (T3) G. corticata so that algae Gracilaria were dried and added to shrimp feed at the rate of 1500 mg per kg and finally, the fourth group (T4) was vaccination group which the shrimp were exposed to the vaccine and injected intramuscularly gamma irradiant WSSV (1µl/gbw) for 10 days. The shrimps of all groups were then injected with WSSV and maintained for 25 days. Results indicated that the survival rates for groups T4, T3 T2 and T1 were 57.05±3.52%, 22.5±0.5%, 15±1.05% and 00.0±0%, respectively. Ultimately, at the end of the study the shrimp group T4 showed higher hematological data: THC, TPP, SOD, POD and PO. The study concluded that gamma irradiant WSSV is effective immunostimulants in shrimp L. vannamei and the immunity has better performances than those of the G. corticata and S. cerevisiae

Feasibility on cage culture of the orange-spotted grouper (Epinephelus coioides)

The present study was carried out to evaluate the possibility of rearing the orange-spotted grouper (E. coioides) juvenile to marketable size in buoyant cages in Khuzestan province coast waters. Juvenile fishes for the study prepared from Bandar-e-Imam Marine Fish Station and reared them in 5-ton fiber glass tank for one year period using common pellet feed and trash fish to reach 50 g mean weight. Young fishes were stocked in 6 rectangular cages (3×3×3 m) to assess their growth performance with two test feeds i.e. pellet feed and trash fish (3 cages for each treatment) with the density of 30 fish /m^3 (810 fish/cage) for 143 days rearing period (started on July). Better growth with significant difference (p0.05). Results also showed that the FCR for the trash fish was acceptable, and hence it is recommended to consider the trash fish price and its labour cost befor using it as the main diet in cage culture activity

Identification and characterization of pathogenic viruses in aquatic animal using advanced techniques in order to develop rapid diagnostic kit (shrimp viral disease kit as well as TSV, HPV and MBV )

Shrimp production increasing rapidly in the world and in2013 the production reaches 4.2 MT. In Iran the shrimp production is under development and estimated in 1393, 20 thousand tons produced. In this regards the important subject is health and disease in shrimp farm. The white spot syndrome virus for second time appears in chabahar and damage many farms. Because the aquaculture activity expand in the world in national, regional and international scale, many emerge disease are endanger. In this regard the viral disease is very important and not only decrease the production but also has a side effect in business and national economy. For control and prevention the viral disease, the accurate methods such as PCR kit were developed. In this project the PCR methods with sensitivity, specificity and efficacy was designed and used for detection viral disease. Many viruses have several serotypes and in different area maybe new serotype induce the disease. For this reason, the specific kit will be design. Three viruses consist of MBV, TSV and IHHNV are very pathogenic in shrimp farm and need the specific PCR kit for detection them. In this project the MBV virus was identified and designs a new primer with Oligo software and the primer amplified a part of DNA with 185 bp in the gel. The specificity and sensitivity of primer were checked by IQ2000 Kit and the primer used for detection unknown samples