Mechanical properties and water purification characteristics of natural jute fiber-reinforced non-cement alkali-activated porous vegetation blocks

This study reports the effects of the volume fraction of natural jute fiber and the content of the alkali activator on the physical and mechanical properties, sulfate ion resistance, and water purification characteristics of non-cement porous vegetation blocks. The volume fractions of the natural jute fiber were 0.0, 0.1, and 0.2 %, and the alkali activator was applied by replacing 5, 6, 7, 8, 9, and 10 % by weight of the blast-furnace slag. Void ratio, compressive strength, sulfate resistance, and water purification characteristics were characterized. The results indicate that increasing natural jute fiber and the alkali activator content increased the void ratio and improved compressive strength and sulfate resistance. pH was not affected by natural jute fiber content but increased with alkali activator content. At alkali activator contents of 9–10 %, the observed compressive strength was similar to that of cement blocks, whereas mixes with alkali activator contents of 8–10 % showed similar or greater void ratios than those of cement blocks. The compressive strength of the cement blocks decreased following immersion in sulfate solutions; however, the compressive strength of the mixes with the alkali activator and blast-furnace slag increased following exposure to sulfates. Water purification characteristics were examined by allowing water to filter through the blocks; the non-cement porous vegetation blocks reduced the suspended solids, 5-day biological oxygen demand, chemical oxygen demand, total nitrogen, and total phosphorous in the water by >40 %.     

RGO/Nylon-6 composite mat with unique structural features and electrical properties obtained from electrospinning and hydrothermal process

In this work, the reduced graphene oxide (RGO) sheets were effectively uploaded through nylon-6 fibers using combined process of electrospinning and hydrothermal treatment. Good dispersion of graphene oxide (GO) with nylon-6 solution could allow to upload GO sheets through nylon-6 fibers and facilitate the formation of spider-wave-like nano-nets during electrospinning. GO sheets present on/into nylon-6 spider-wave-like nano-nets were further reduced to RGO using hydrothermal treatment. The impregnated GO sheets into nylon-6 nanofibers and their reduction during hydrothermal treatment were confirmed by FE-SEM, TEM, FT-IR and Raman spectra. The electrical characteristics of pristine nylon-6, GO/nylon-6 and RGO/nylon-6 nanofibers were investigated and it was found that RGO/nylon-6 composite mat had better electrical conductivity than others. The formation of spider-wave-like nano-nets as well as indirect route of incorporation of RGO sheets on electrospun nylon-6 mat may open a new direction for future graphene/polymer electronics.     

Evaluation of dietary natural mineral materials as an antibiotic replacer on growth performance,non‐specific immune responses and disease resistance in rainbow trout,Oncorhynchus mykiss

We evaluated the effects of some dietary natural mineral materials as an antibiotic replacer based on growth performance, non‐specific immune responses and disease resistance in juvenile and subadult rainbow trout, Oncorhynchus mykiss. First experiment, juvenile rainbow trout averaging 2.7 ± 0.02 g (mean ± SD) were fed one of the six experimental diets; a basal commercial diet as a control (CON), CON with oxytetracycline (OTC), with yellow loess (YL), with Macsumsuk^® (MS), with Song‐Gang^® stone (SG) and with barley stone (BS) at 0.4% of each diet. At the end of 8‐week feeding trial, weight gain (WG), specific growth rate (SGR), feed efficiency (FE) and protein efficiency ratio (PER) of fish fed YL diet were significantly higher than those of fish fed CON diet. Non‐specific immune responses such as superoxide dismutase (SOD), myeloperoxidase (MPO), lysozyme (LYS) activity and oxidative radical production of fish fed YL diet were higher than those of fish fed CON diet. At the end of 15 days of challenge test with Aeromonas salmonicida, average cumulative survival rate of fish fed YL diet was significantly higher than that of fish fed BS and CON diets. However, there were no significant differences among fish fed YL, SG and OTC diets. Second experiment, subadult rainbow trout averaging 261.5 ± 3.5 g (mean ± SD) were fed one of the four experimental diets for 22 weeks: CON, and CON with OTC, YL or SG at 0.4% of each diet. At the end of feeding, growth performance of fish fed SG and YL diets was significantly higher than that of fish fed CON diet. Non‐specific immune responses in terms of SOD, MPO, LYS and NBT of fish fed SG and YL diets were significantly higher than those of fish fed CON diet. However, there were no significant differences among the fish fed YL, SG and OTC diets. The results indicate that dietary yellow loess or Song‐gang^® stone at 0.4% of diet could replace oxytetracycline in juvenile and subadult rainbow trout.     

Botanical origin and chemical composition of Brazilian propolis

Brazilian propolis has been classified into 12 groups based on physicochemical characteristics: five in the southern Brazil group (group 3), one in the southeastern Brazil group (group 12), and six in the northeastern Brazil group (group 6). The plant origins of these groups were investigated using reversed-phase high-performance thin-layer chromatography (RPHPTLC), reversed-phase high-performance liquid chromatography (RPHPLC), and gas chromatography-mass spectrometry (GC-MS). It was concluded that the origins of propolis group 3, group 6, and group 12 are resins of the poplar tree, Hyptis divaricata, and Baccharis dracunculifolia, respectively.     

Nitrite Toxicity and Methemoglobin Changes in Southern Flounder,Paralichthys lethostigma,in Brackish Water

This study was performed to estimate the nitrite toxicity to southern flounder, Paralichthys lethostigma, in brackish water (7.5 ppt of salinity). For a LC₅₀ test, 20 fingerlings (5.7 ± 0.4 cm) in each aquarium (15 L) were exposed to the concentrations of 0, 1, 5, 10, 15, 30, 60, 120, and 240 mg NO₂^?‐N/L in duplication for 10 d. Median lethal concentration at 96 h (96‐h LC₅₀) was calculated as 81.6 mg NO₂^?‐N/L. For a verification test, young flounder (164.2 ± 9.1 g) were exposed to a simulated culture condition in recirculating systems (1000 L). Sodium nitrite was not added to control system, whereas it was added to Treatment system 1 (TS 1) and Treatment system 2 (TS 2) to maintain nitrite concentrations of 20 and 30 mg NO₂^?‐N/L, respectively. The plasma nitrite concentrations of the young flounder in TS 1 and TS 2 were 4.5 and 6.6 mg NO₂^?‐N/L, respectively, after 2 wk. At this time, the methemoglobin percentages in TS 1 and TS 2 reached 85.8 and 89.7%, and survival rates were 37.5 and 25.0%, respectively. The results of these tests indicate that southern flounder do not concentrate nitrite in blood from the environment, but they seem to be more sensitive to nitrite compared with other species that do not concentrate nitrite.     

Cross-protective immunity and the serological classification system for Bacteroides nodosus

The relationship between the serological classification system for serogroup B and for serogroup H of Bacteroides nodosus and cross-protection between subgroups within these serogroups was examined. Protection against ovine footrot following vaccination was achieved against other subgroup strains provided sufficient cross-reactive antibody was induced by shared pilus antigens. Within serogroup B, better cross-protection against one subgroup was obtained with a pili vaccine than a whole cell vaccine which correlated with higher pilus antibody titres induced by the former. For serogroup H, a lack of cross-protection and serological reactivity between subgroups was demonstrated, which indicates that the prototype strain of subgroup H2 should be designated a new serogroup.     

The effect of an extended artificial photoperiod and gonadotrophin-releasing hormone infusions in inducing fertile oestrus in anoestrous mares

The occurrence of fertile oestrus early in the breeding season is of paramount importance to the Thoroughbred industry to facilitate early conception. This paper compares 2 techniques for inducing fertile oestrus in anoestrous mares using either an extended photoperiod alone or together with gonadotrophin-releasing hormone (GnRH) infusions. Eleven mares were placed under conditions of 16 h light and 8 h darkness and 5 of these were implanted with osmotic minipumps delivering approximately 100 ng GnRH/kg/h for 28 days (treated mares). The treated mares ovulated 27.7 days earlier than and conceived 32 days earlier than the 6 mares not given GnRH. GnRH-induced ovulations were followed by a competent luteal phase. The combination of GnRH pumps implanted 2 weeks before commencement of service together with extended photoperiod from July 1 has promise in assisting the stud breeder to improve reproductive efficiency on commercial stud farms.     

Antagonistic effects of yohimbine in pigs anaesthetised with tiletamine/zolazepam and xylazine

Twelve healthy two-month-old Landrace x Yorkshire pigs of both sexes were randomly assigned to receive either tiletamine and xylazine (zx) or zolazepam and xylazine followed 20 minutes later by yohimbine (zxy). The pigs' scores for immobilisation and analgesia, and their rectal temperature, heart rate, respiration rate, pO(2), pCO(2), alkaline phosphatase, aspartate aminotransferase, glucose and total plasma proteins were determined before and five, 25, 45, 65 and 85 minutes after the administration of the tiletamine/zolazepam and xylazine. The mean total scores for immobilisation and analgesia of the zxy pigs were significantly lower than those of the zx pigs after 85 minutes. The mean rectal temperatures of the zxy pigs were significantly lower than those of zx pigs after 25, 45 and 65 minutes. The mean respiratory rates of the zx pigs were significantly lower than those of zxy pigs after five minutes. The mean pCO(2) of the zxy pigs were significantly lower than those of zx pigs five minutes after the administration of yohimbine. The mean glucose concentration of the zxy pigs were significantly lower than those of zx pigs after 65 and 85 minutes. The mean concentration total protein of the zxy pigs were significantly lower than those of zx pigs throughout the period of anaesthesia. Both groups became laterally recumbent within three minutes. When recovering from anaesthesia, the pigs treated with yohimbine took significantly less time to achieve sternal recumbency (mean [sd] 52.2 [8.9] v 76.2 [20.6] minutes) and less time to be able to stand (mean [sd] 77.0 [9.8] v 98.7 [15.8] minutes), and walk (mean [sd] 81.3 [11.3] v 110.8 [18.6] minutes).