Effect of stocking density on the growth of Thai pangas, Pangasius sutchi (Fowler) in net cage fed on formulated diet

A three month long experiment was conducted to observe the effect of stocking density on the growth of Pangasius sutchi in net cages. The size of each cage was 1m³.The three stocking densities used were 40, 50 and 60 fishes/m³ and designated as treatment T1, T2 and T3 respectively. Each treatment had three replicates. All the fishes were of same age group having mean length and weight of 7.13 ± 1.37 cm and 2.46 ± 0.12 g respectively. The fish in all the net cages were fed a diet containing 34% protein. The result of the study showed that fish in the treatment T1 stocked at the rate of 40 fish/m³ resulted the best individual weight gain followed by T2 and T3 respectively. The specific growth rate (SGR) ranged between 3.51 and 3.09, the food conversion ratio (FCR) values ranged between 1.73 and 2.04 with treatment T1 resulting the lowest FCR. The protein efficiency ratios (PER) values were 1.69, 1.16 and 1.43 for treatment T1, T2 and T3 respectively. There was no significant (P>0.05) variation among the survival rates of fish which ranged between 92 and 95%. The net productions in different treatments were 2189, 2343, and 2283g for treatment T1, T2 and T3 respectively. The result of the present study indicated that the best individual growth of P. sutchi was obtained at a density of 40 fish/m³ but the highest total production was obtained at a stocking density of 50 fish/m³ in net cages

Effects of duckweed (Lemna minor) as dietary fishmeal substitute for silver barb (Barbodes gonionotus Bleeker)

A 60-day long growth trial was conducted to evaluate the suitability of duckweed Lemna minor as dietary fish meal substitute for silver barb (Borbodes gonionotus Bleeker). Five iso-nitrogenous diets were formulated to contain 35% protein and each treatment had three replicates with 15 fish in each aquarium with a mean initial weight of 1.5 ± 0.2 g. Duckweed was used in the experiment to replace 10, 20, 30 and 35% of the dietary fish meal in diet 2, 3, 4 and 5 respectively. Fish meal was used as the sole source of protein in control diet (Diet 1). Fish were fed three times daily at satiation level. In terms of growth, food conversion and protein utilization, the control diet and diet containing 17.07% duckweed showed the best (P<0.05) performance followed by diets containing 34.14%, 51.21% and 59.24% duckweed. Fish fed diets containing higher levels of duckweed had higher carcass moisture and lower lipid content compared to the control diet. Histopathological examination revealed abnormalities in the liver of fish fed diets containing higher inclusion of duckweed. It was noted that 10% of the dietary fish meal protein could be replaced by duckweed (L. minor) in the diet of silver barb (B. gonionotus)

Differential game model and coordination model for green supply chain based on green technology research and development

The purpose of this paper is to establish a green supply chain differential game model for green technology research and development based on a secondary green supply chain composed of a single manufacturer and a single retailer. It compares the differential game equilibrium solutions under centralized and decentralized decision-making. The green supply chain members are coordinated through the dynamic wholesale price mechanism, and numerical simulation is used as a methodology, to verify and explain the results. The study found that compared to decentralized decision-making, the level of green technology and the total profit of green channels are higher under centralized decision-making. When the coordination parameters are within a certain range, the dynamic wholesale price mechanism can coordinate the behavior of manufacturers and retailers. The result also discovers that under the dynamic wholesale price mechanism, with the increase of investment cost coefficient, or the increase of price sensitivity or the decrease of consumer's environmental awareness, the green technology level, product green degree, price, retailer's profit, and the total profit of green channel is decreased. In contrast, the wholesale price and manufacturer's profits are increased

A Study on Industrial Waste Effluents and Their Management at Selected Food and Beverage Industries of Bangladesh

Various types of waste effluents produced by two industries were studied to verify their environmental effects and to prepare a suggestion for management of those wastes. Two types of wastes were considered- wastewater and solid wastes. Analysis on three samples of wastewater was performed to determine the physical, chemical, organic and biological pollution. The pH values were 6.58, 6.75 &amp; 6.64; amount of TDS were 235, 241 &amp; 270 ppm; total hardness were 126, 123 &amp; 144 ppm; calcium hardness were 105, 99 &amp; 122 ppm, all the values of P-alkalinity were zero and values of M-alkalinity were 40, 40 &amp; 45 mg/l. Iron concentrations were 0.21, 0.18 &amp; 0.19 mg/l. Their Cl2 test proved absence of Cl2 Molecule. Only one sample was analyzed for bacterial viable count (44x105 cfu/ml), fungal test (fungi were absent), DO (6.8 mg/l), BOD (156 mg/1) and COD (267 mg/1). Results suggested that iron concentrations, pH values, TDS and DO were within the standard range. Level of total hardness, alkalinity, BOD, COD and total bacterial count exceeded level of standards. Their effects were evaluated from secondary data sources. Solid waste quality and the current onsite waste management facilities were studied through questionnaire survey and direct observations. Most of the cases, current waste management systems were old fashioned and indigenous. After studying literature on waste management procedures, a waste management plan for these industries has been prepared. Study results show that, these selected industries do produce few waste linked problems which can be minimized following some strict management measures

Association between clinically diagnosed lumbar intervertebral disc prolapse and magnetic resonance image findings

There are contradictory reports on the findings of magnetic resonance image (MRI) in lumbar intervertebral disc prolapse. A study was conducted on 54 patients using 3 of 4 clinical criteria (low back pain with radiation down to the lower limbs, radicular pain along specific dermatomes, positive straight leg raising test, presence of neurological symptoms and signs e.g. motor or sensory deficit and MRI of lumbosacral spine of the respondent). Evaluation of MRI of lumbosacral spine was done based on extent of disc prolapse, disc degeneration, nerve root compression neural foramen compromise. The logistic regression analysis between the findings of MRI and the clinical features show that there was a significant association in the neural foramen or lateral recess (Odd's ratio 7.106, p&lt;0.05), the root compression (p&lt;0.01) as well as the disc extrusion (p&lt;0.05). There was no statistical association between clinical levels and other MRI findings like disc protrusion and disc bulge (p value 0.21 and 0.14, respectively). The strength of agreement between clinical and MRI diagnosis level of disc prolapse was calculated using kappa statistics (k-value). The test revealed a very good agreement for L3/4 (k-value = 0.812) and good agreement for L4/5 and L5/SI  level (k-value 0.75 and 0.75 respectively) between these two procedures, suggesting that level of disc prolapse could be correctly  diagnosed without MRI findings.  In conclusion, clinically diagnosed levels associate well with MRI levels, but all MRI abnormalities do not have any clinical significance.

On the Digital Holographic Interferometry of Fibrous Material, I. Optical Properties of Polymer and Optical Fibers

The digital holographic interferometry (DHI) was utilized for investigating the optical properties of polymer and optical fibers. The samples investigated here were polyvinylidene fluoride (PVDF) polymer fiber and graded-index (GRIN) optical fiber. The phase shifting Mach-Zehnder interferometer was used to obtain five phase-shifted holograms, in which the phase difference between two successive holograms is pi/2, for each fiber sample. These holograms were recorded using a CCD camera and were combined to gain a complex wavefield, which was numerically reconstructed using the convolution approach into amplitude and phase distributions. The reconstructed phase distribution was used to determine the refractive index, birefringence and refractive index profile of the studied samples. The mean refractive index has been measured with accuracy up to 4 {\times} 10-4. The main advantage of DHI is to overcome the manual focusing limitations by means of the numerical focusing. The results showed accurate measurements of the optical properties of fibers.Comment: abstract, reference

Ethnic Association in Primary Systemic Vasculitis: A Systematic Review

Background: Literature described wide disparities in incidence and prevalence between different types of vasculitis. There were no comprehensive studies on ethnic or racial associations in all types of primary systemic vasculitis (PSV) in any published article, until this review commenced in 2020. The purpose of the review is to synthesize the evidence regarding the relation of ethnicity and the incidence and/or prevalence of different types of PSV. Methods: A total of 52 selected articles which include Clinical trials, cohorts, cross-sectional studies, case series, and case studies and have been published within the last 10 years in the human population, were reviewed by searching The Medline, PubMed, and Google Scholars databases using predefined keywords. The PRISMA diagrams were followed to identify relevant articles. The methodological qualities of the studies were assessed using the EPHPP tool. Finally, a summary of the evidence on the association between ethnic origin and PSV was painstakingly compiled. Results: The connection between ethnicity and different types of PSV has been found to be significantly diverse in this research such as vasculitis is more common in Asians and Scandinavians, Kawasaki disease and periarteritis nodules are more prevalent in Japanese and Alaska-natives, ANCA-associated vasculitis is more frequent in Caucasians, whereas Henoch-Schonlein purpura and Cogan syndrome more usual in Caucasians and Asians. Furthermore, Behçet's disease more commonly occurs on the "Silk Road", especially in Turkey. Conclusion: Genetic susceptibility and environmental elements could be the contributing factors to the global variation in the incidence and prevalence of primary systemic vasculitis

Plant pest surveillance: from satellites to molecules

Open Access Article; Published online: 15 Mar 2021Plant pests and diseases impact both food security and natural ecosystems, and the impact has been accelerated in recent years due to several confounding factors. The globalisation of trade has moved pests out of natural ranges, creating damaging epidemics in new regions. Climate change has extended the range of pests and the pathogens they vector. Resistance to agrochemicals has made pathogens, pests, and weeds more difficult to control. Early detection is critical to achieve effective control, both from a biosecurity as well as an endemic pest perspective. Molecular diagnostics has revolutionised our ability to identify pests and diseases over the past two decades, but more recent technological innovations are enabling us to achieve better pest surveillance. In this review, we will explore the different technologies that are enabling this advancing capability and discuss the drivers that will shape its future deployment