Biomonitoring potentially toxic elements in atmospheric particulate matter of greater Dhaka region using leaves of higher plants.

In this study, four different plant species, namely Artocarpus heterophyllus, Mangifera indica, Psidium guajava, and Swietenia mahagoni, were selected from seven different locations to assess the feasibility of using them as a cost-effective alternative for biomonitoring air quality. Atmospheric coarse particulate matter (PM10), soil samples, and leaf samples were collected from residential, industrial, and traffic-congested sites located in the greater Dhaka region. The heavy metal concentrations (Cd, Cr, Cu, Fe, Mn, Ni, Pb, and Zn) in the leaves of the different species, PM10, and soil samples were analyzed. The highest Pb (718 ng/m3) and Zn (15,956 ng/m3) concentrations were found in PM10 of Kodomtoli which is an industrial area. On the other hand, the highest Fe (6,152 ng/m3) and Ni (61.1 ng/m3) concentrations were recorded in the PM10 of Gabtoli, a heavy-traffic area. A significant positive correlation (r = 0.74; p < 0.01) between Pb content in plant leaves and PM fraction was found which indicated that atmospheric PM-bound Pb may contribute to the uptake of Pb by plant leaves. The analysis of the enrichment factor (EF) revealed that soils were contaminated with Cd, Ni, Pb, and Zn. The abaxial leaf surfaces of Psidium guajava growing at the polluted site exhibited up to a 40% decrease in stomatal pores compared to the control site. Saet's summary index (Zc) demonstrated that Mangifera indica had the highest bioaccumulation capacity. The metal accumulation index (MAI) was also evaluated to assess the overall metal accumulation capacity of the selected plants. Of the four species, Swietenia mahagoni (3.05) exhibited the highest MAI value followed by Mangifera indica (2.97). Mangifera indica and Swietenia mahagoni were also found to accumulate high concentrations of Pb and Cr in their leaves and are deemed to be good candidates to biomonitor Pb and Cr contents in ambient air.

A potential toxicological risk assessment of heavy metals and pesticides in irrigated rice cultivars near industrial areas of Dhaka, Bangladesh.

Rice intake represents a significant pathway through which humans accumulate heavy metals. This study presents a comprehensive analysis of heavy metal and pesticide contamination in rice cultivars irrigated with industrial wastewater near Dhaka, Bangladesh, a region heavily influenced by industrial activities. This study employed a unique methodology that not only quantified the concentrations of heavy metals and pesticide residues in rice grains but also extended to evaluating the physicochemical properties of rice stems, husks, soil, and irrigation water. The findings revealed alarmingly high levels of heavy metals such as lead, cadmium, chromium, nickel, and mercury in the soil and irrigation water, with concentrations in some cases exceeding the World Health Organization safety thresholds by 2 to 15 times. Notably, the rice grains also exhibited significant contamination, including substantial amounts of diazinon and fenitrothion pesticides, exceeding the established safety limits. The study employed hazard quotients (HQs) and cancer risk (CR) assessments to evaluate the potential health risks associated with the consumption of contaminated rice. The results indicated HQ values were greater than 1 for rice grains across the sampled fields, suggesting a considerable non-carcinogenic health risk, particularly from lead exposure, which was found at levels twice the standard limit in all the sampling fields. Moreover, the CR values for As, Pb, Cd, Co, and Mn highlighted a significant carcinogenic risk in several instances.

Electrodeposition of iron from 1-ethyl-3-methylimidazolium trifluoromethanesulfonate and reverse microemulsions of Triton X-100.

Electrodeposition of iron (Fe) was investigated in three different media, namely a hydrophilic ionic liquid (IL), 1-ethyl-3-methylimidazolium trifluoromethanesulfonate, conventional reverse microemulsion (RME)/reverse micellar solution, and IL-based RME of a non-ionic surfactant, Triton X-100, with a view to electrodepositing iron with desired morphology. Electrochemical behaviour of Fe2+ was studied using cyclic voltammetric technique with a copper electrode as the working electrode. Electrochemical reduction of Fe2+ in all the studied media was found to be an electrochemically irreversible, diffusion-controlled process. Successful potentiostatic electrodeposition of metallic iron was performed in all the studied media on copper substrate using bulk electrolysis method. The obtained iron electrodeposits were characterized using a scanning electron microscope and an X-ray diffractometer. The controlled diffusion of Fe2+ towards electrode surface in all the media resulted in the formation of nanoparticles of iron, but compact layers of granular nanoparticles could be achieved from both the conventional and IL-based RME systems. The IL-based microemulsions synergistically combined the advantageous features of both the IL and RME and showed promise for tuning the size, shape, and morphology of the electrodeposited iron.

Dissolution of cellulose in imidazolium-based double salt ionic liquids.

The dissolution of cellulose in double salt ionic liquids (DSILs) was studied in detail and compared with the dissolution in individual constituent ionic liquids (ILs). The DSILs, [C4mim](CH3CO2)xCl1-x (x is the mole fraction of the single component ILs), were synthesized using acetate and chloride salts of 1-butyl-3-methylimidazolium. These DSILs were then used for the investigation of the solubility of cellulose in the whole mole fraction range. Commercial cellulose (CC) powder, kraft pulp (KP), and prehydrolysis kraft pulp (PHKP) of jute were chosen as cellulose sources. The solubility of cellulose increased with an increasing temperature for [C4mim](CH3CO2)0.6Cl0.4 and with increasing amount of [C4mim]Cl in DSILs. The maximum solubility of CC powder was 32.8 wt% in [C4mim](CH3CO2)0.6Cl0.4 at 100 °C, while for KP and PHKP, solubilities were 30.1 and 30.5 wt%, respectively under the identical condition. Cellulose could be regenerated from the DSILs using water as an antisolvent. Structure, morphology, and thermal stability of the regenerated cellulosic materials were analyzed. DSILs could be recycled >99 % without a discernible change in structure. This work demonstrates that DSILs display enhanced solubility over ILs system and have potential as a chemical processing methodology.

Clinical anatomy of the head region of the black bengal goat in Bangladesh / Anatomía clínica de la región de la cabeza de la cabra negra bengal en Bangladesh

The study involved the measurements of some clinically important landmarks for regional anesthesia in the maxillary and mandibular regions of head of fifty Black Bengal (BB) goats. The distance from facial tuberosity to the infra-orbital canal and from the latter to the root of the alveolar tooth directly ventral to it were 1.85 cm and 1.75 cm respectively. Both the distances from facial tuberosity to infra-orbital canal and from infra-orbital canal to the root of the alveolar tooth are of clinical important even in live animal as a guide for tracking infra-orbital nerve because of facial tuberosity. The distance between the lateral end of the alveolus of the incisor tooth to the mental foramen was 2.11 cm and are from the mental foramen to the caudal mandibular border was 11.69 cm and important for the regional anesthesia of mental nerve. The length and maximum height of the mandibles were 14.21 cm and 8.83 cm respectively. The distance from Caudal border of mandible to below mandibular foramen was 1.47 cm, while the distance from the mandibular foramen to the base of the mandible, Caudal border of mandibular to the level of mandibular foramen and mandibular foramen to border of mandibular angle were 3.64cm, 0.90 cm and 2.65 cm respectively. Parameters regarding mandible are of c linical important landmarks and will be guide for the regional anesthesia of mandibular nerve block. However, these data was discussed with regard to their application in proper tracking of infra-orbital, mental and mandibular nerves in aid of regional anesthetic procedures for the clinical affection around the head of the Black Bengal goat.

El estudio incluyó la medición de algunos puntos anatómicos de importancia clínica para la anestesia regional en las regiones superior e inferior de la cabeza de cincuenta cabras Negras de Bengal (BB). La distancia desde la tuberosidad facial hasta el canal infraorbitario y de éste a la raíz del diente alveolar directamente ventral a él fueron 1,85 cm y 1,75 cm, respectivamente. Tanto las distancias desde la tuberosidad facial hasta el canal infraorbitario y desde el canal infraorbitario a la raíz del diente alveolar fueron importancia clínica en animales vivos como una guía para el seguimiento del nervio infraorbitario a través de la tuberosidad facial. La distancia entre el extremo lateral de los alvéolos de los dientes incisivos al foramen mental fue de 2,11 cm y desde el foramen mental al borde mandibular caudal fue 11,69 cm y es importante para la anestesia regional del nervio mentoniano. La longitud y la altura máxima de las mandíbulas fueron 14,21 cm y 8,83 cm respectivamente. La distancia desde el borde caudal de la mandíbula por debajo del foramen mandibular fue de 1,47 cm, mientras que la distancia desde el foramen mental hasta la base de la mandíbula, desde el borde caudal de la mandíbula a nivel del foramen mandibular y del foramen mandibular hasta el borde del ángulo mandibular fueron 3,64cm , 0,90 cm y 2,65 cm, respectivamente. Los parámetros en relación con la mandíbula son puntos anatómicos de importancia clínica y sirven de guía para la anestesia regional del bloqueo del nervio mandibular. No obstante, estos datos fueron discutidos en relación a su aplicación en el seguimiento adecuado de las infraestructuras de los nervios infraorbitario, mental y mandibular en ayuda a procedimientos anestésicos regionales para el uso clínico alrededor de la cabeza de cabra de Bengal Negra.