Chirality at metal and helical ligand folding in optical isomers of chiral bis(naphthaldiminato)nickel(II) complexes

Enantiopure bis[(R or S)-N-1-(Ar)ethyl-2-oxo-1-naphthaldiminato-κ2N,O]nickel(ii) complexes Ar = C6H5 (1R or 1S), p-OMeC6H4 (2R or 2S), and p-BrC6H4 (3R or 3S) are synthesized from the reactions between (R or S)-N-1-(Ar)ethyl-2-oxo-1-naphthaldimine and nickel(ii) acetate. Circular-dichroism spectra and their density-functional theoretical simulation reveal the expected mirror image relationship between the enantiomeric pairs 1R/1S and 3R/3S in solution. CD spectra are dominated by the metal-centered Λ- or Δ-chirality of non-planar four-coordinated nickel, this latter being in turn dictated by the ligand chirality. Single crystal structure determination for 1R and 1S shows that there are two symmetry-independent molecules (A and B) in each asymmetric unit that give a Z′ = 2 structure. Two asymmetric and chiral bidentate N^O-chelate Schiff base ligands coordinate to the nickel atom in a distorted square planar N2O2-coordination sphere. The conformational difference between the symmetry-independent molecules arises from the "up-or-down" folding of the naphthaldiminato ligand with respect to the coordination plane, which creates right- (P) or left-handed (M) helical conformations. Overall, the combination of ligand chirality, chirality at the metal and ligand folding gives rise to discrete metal helicates of preferred helicity in a selective way. Cyclic voltammograms (CV) show an oxidation wave at ca. 1.30 V for the [Ni(L)2]/[Ni(L)2]+ couple, and a reduction wave at ca. -0.35 V for the [Ni(L)2]/[Ni(L)2]- couple in acetonitrile

Niemann Pick disease: a rare lysosomal storage disease

Niemann Pick Disease (NPD) is a rare autosomal recessive lysosomal storage disease characterized by lysosomal lipid storage. The disease is caused by deficiency of enzyme, acid sphingomyelinase (ASM) which leads to accumulation of sphingomyelin & other lipids in reticuloendothelial cells of various organs like liver, spleen, bone marrow, lymph node, brain, nerves and kidney. Four types of the disease have been identified i.e. A, B, C and D. We report a case of Niemann Pick Disease type C. The patient was a 2.5 years female child who presented with developmental regression, recurrent seizures, failure to thrive and hepatospleenomegaly. Bone marrow (BM) aspiration was performed which showed hypercelluler marrow with few fat laden macrophage resembling foam cell that are characteristics of this disease. BSMMU J 2022; 15(2): 141-14

A study of electromagnetic fields in horn antennas containing two eielectrics

Due to the character of the original source materials and the nature of batch digitization, quality control issues may be present in this document. Please report any quality issues you encounter to [email protected], referencing the URI of the item.Not availabl

Axial propagation of neutron waves in heterogeneous media

A theoretical study of the axial propagation of plane-thermalneutron waves in a semi-infinite heterogeneous subcritical assembly containing cylindrical fuel rods in a square pattern is performed in the framework of the P-1 approximation to the Boltzmann equation. The method is based on a modified form of heterogeneous reactor theory due to Feinberg and Galanin. The analysis is first carried out in the one group P-1 approximation and then extended to age diffusion theory. Axial propagation of neutron waves is studied, analytically and numerically, by analyzing the time dependent part of the moderator flux in the assembly. On oscillating plane source of thermal neutrons placed at one face of the assembly is assumed to inject a plane wave of thermal neutrons which propagate along a direction parallel to the fuel rods. The thermalization effect is considered by assuming a time delay prior to appearance of the fission neutrons in the thermal group. The analysis predicts that the phase interference between the modes of propagation in the axial direction may five rise to resonances in the frequency response of the asymptotic moderator flux. A standing-wave-pattern is also predicted in the amplitude distribution of the oscillating part of the moderator flux in the axial direction. The relationship between the resonances and the system parameters are investigated. An experimental method which can be useful for the determination of the system parameters is suggested for systems in which the frequency response (of the amplitude and the phase) and the standing-wave-pattern can be measured

Response of rice to soil phosphorus levels

Due to the character of the original source materials and the nature of batch digitization, quality control issues may be present in this document. Please report any quality issues you encounter to [email protected], referencing the URI of the item.Not availabl

Axial propagation of neutron waves in heterogeneous media

A theoretical study of the axial propagation of plane-thermalneutron waves in a semi-infinite heterogeneous subcritical assembly containing cylindrical fuel rods in a square pattern is performed in the framework of the P-1 approximation to the Boltzmann equation. The method is based on a modified form of heterogeneous reactor theory due to Feinberg and Galanin. The analysis is first carried out in the one group P-1 approximation and then extended to age diffusion theory. Axial propagation of neutron waves is studied, analytically and numerically, by analyzing the time dependent part of the moderator flux in the assembly. On oscillating plane source of thermal neutrons placed at one face of the assembly is assumed to inject a plane wave of thermal neutrons which propagate along a direction parallel to the fuel rods. The thermalization effect is considered by assuming a time delay prior to appearance of the fission neutrons in the thermal group. The analysis predicts that the phase interference between the modes of propagation in the axial direction may five rise to resonances in the frequency response of the asymptotic moderator flux. A standing-wave-pattern is also predicted in the amplitude distribution of the oscillating part of the moderator flux in the axial direction. The relationship between the resonances and the system parameters are investigated. An experimental method which can be useful for the determination of the system parameters is suggested for systems in which the frequency response (of the amplitude and the phase) and the standing-wave-pattern can be measured

STRUCTURAL INTERRELATIONSHIPS OF VARIOUS SECTORS OF THE ECONOMY OF BANGLADESH WITH SPECIAL EMPHASIS ON AGRICULTURE

There is a great interdependence between various sectors of an economy. An input-output table describes social accounts for the whole economy and reflects the interdependence of industries. The total change of economy from any specified change in final demand in an industry is assessed by the extent of interaction of the sectors. Sectoral output, income and employment generated in the economy are used to policy decision regarding investment or other government expenditure on sectoral output, income and employment. Thus, the present study was undertaken with a view to find out the structural interrelationships among the different sectors and to assess the sectoral potentiality of the economy. The latest input-output table containing 79 sectors constructed by the Bangladesh Planning Commission was used. Manufacturing uses higher amounts of intermediate agricultural inputs and it is a dominant sector producing the highest total output (36.9 per cent of the total output). Among the agricultural production sectors, wheat, oilseeds, tobacco and major spices have high import contents whereas the agro-based manufacturing sectors have low import requirements. A strong interrelation exists between the manufacturing sectors and primary agricultural sectors which supply the basic raw materials to manufacturing sectors. The agro-processing industries generate higher income and employment whereas most of the manufacturing sectors other than agro-processing sectors show comparatively lower employment generation. The income and employment multiplier values were relatively much smaller for most of the primary sectors, service sectors and trade sectors

SOCIOECONOMIC FACTORS INFLUENCING NUTRITIONAL STATUS OF UNDER-FIVE CHILDREN OF AGRARIAN FAMILIES IN BANGLADESH: A MULTILEVEL ANALYSIS

The nutritional status of under five children is a sensitive sign of a country's health status as well as economic condition. This study investigated differential impact of some demographic, socioeconomic, environmental and health related factors on nutritional status among under five children in Bangladesh whose fathers' occupation was agriculture. The study used Bangladesh Demographic and Health Survey 2007 data. Bivariate analysis, multivariate analysis (Cox's linear logistic regression model) and two-level random intercept binary logistic regression analysis were used to identify the determinants of under-five malnutrition. The analyses revealed that 19.6 percent of the children were severely stunted, 29.4 percent were moderately stunted and 51 percent were not stunted. This study also found that 3.5 percent of the children were severely wasted, 16.5 percent were moderately wasted and 80 percent were not wasted. Furthermore, the analyses revealed that 14.5 percent of the children were severely underweight, 32.5 percent were moderately underweight and 53 percent children were not underweight. The main contributing factors for under five malnutrition were found to be child's age, birth order, mother's education, father's education, family wealth index, sanitation facility, place of delivery, place of residence and division. Community level variations were found significant for wasting only in the analyses

PRODUCTIVITY AND RESOURCE USE EFFICIENCY OF MILK PRODUCTION OF THE SMALL SCALE DAIRY FARMERS

The study investigated the productivity and resource use efficiency of milk production of small scale dairy farmers in Bangladesh. A total of 280 cattle farmers were interviewed in five different districts of Bangladesh. The selection of sample was done using stratified random sampling technique. Apart from descriptive analyses, two types of models such as CobbDouglas type stochastic frontier production function and conventional average Cobb-Douglas type income function was estimated. Milk production of crossbreed was found significantly higher than that of indigenous cow. Farmer's education was positively associated with technical efficiency in milk production. Some important predictors of household income were identified. Analyses further suggested that milk production of local breed and crossbred cow can be increased by 41% and 40%, respectively by increasing the farmer's technical efficiency with the same resource base and technologies. The study recommended that all the livestock farmers should be given training on technical aspects of milk production and livestock health with a view to increasing milk production

Designing a Reliable and Congested Multi-Modal Facility Location Problem for Biofuel Supply Chain Network

This study presents a mathematical model that designs a reliable multi-modal transportation network for a biofuel supply chain system while site-dependent facility failure and congestion are taken into consideration. The proposed model locates the multi-modal facilities and biorefineries and determines the optimal production, storage, and routing plans in such a way that the overall system cost is minimized. We propose a hybrid Constraint generation-based Rolling horizon algorithm to solve this challenging NP-hard problem. The performance of this algorithm is tested in a example case study with numerical analysis showing that the hybrid algorithm can find near-optimal solutions to large-scale problem instances in a reasonable amount of time. Results indicate that the effect of congestion reduces the usage of multi-modal facilities in the biofuel supply chain network while bio-refineries and multi-modal facilities tend to move away from coastal areas when disruption probabilities are taken into consideration