Remediation techniques for elimination of heavy metal pollutants from soil: A review.

Contaminated soil containing toxic metals and metalloids is found everywhere globally. As a consequence of adsorption and precipitation reactions, metals are comparatively immobile in subsurface systems. Hence remediation techniques in such contaminated sites have targeted the solid phase sources of metals such as sludges, debris, contaminated soils, or wastes. Over the last three decades, the accumulation of these toxic substances inside the soil has increased dramatically, putting the ecosystem and human health at risk. Pollution of heavy metal have posed severe impacts on human, and it affects the environment in different ways, resulting in industrial anger in many countries. Various procedures, including chemical, biological, physical, and integrated approaches, have been adopted to get rid of this type of pollution. Expenditure, timekeeping, planning challenges, and state-of-the-art gadget involvement are some drawbacks that need to be properly handled. Recently in situ metal immobilization, plant restoration, and biological methods have changed the dynamics and are considered the best solution for removing metals from soil. This review paper critically evaluates and analyzes the numerous approaches for preparing heavy metal-free soil by adopting different soil remediation methods.

Molecular detection of Leishmania species in human and animals from cutaneous leishmaniasis endemic areas of Waziristan, Khyber Pakhtunkhwa, Pakistan

Objectives:To detect Leishmania species in human patients, animal reservoirs and Phlebotomus sandflies in Waziristan, Pakistan.Methods:Tissue smears and aspirates from 448 cutaneous leishmaniasis (CL) suspected patients were analyzed. To sort out role of the reservoir hosts, skin scrapings, spleen and liver samples from 104 rodents were collected. Furthermore, buffy coat samples were obtained from 60 domestic animals. Sandflies were also trapped. All human, animals and sandfly samples were tested by microscopy, kinetoplastic PCR and internal transcribed spacer 1 (ITS1) PCR followed by restriction fragment length polymorphism for detection of Leishmania species.Results:An overall prevalence of 3.83% and 5.21% through microscopy and ITS1 PCR respectively was found. However, the statistically non-significant correlation was found between area, gender, and number of lesions. The presence of rodents, sandflies, domestic animals and internally displaced people increased the risk of CL. Using ITS1-PCR-RFLP, Leishmania tropica (L. tropica) was confirmed in 106 samples while 25 of the isolates were diagnosed as Leishmania major (L. major). Similarly, 3/104 rodents were positive for L. major and 14 pools of DNA samples containing Phlebotomus sergenti sandflies were positive for L. tropica. None of samples from domestic animals were positive for leishmaniasis.Conclusions:In the present study, L. tropica and L. major are found to be the main causative agents of CL in study area. Movement of internally displaced people from CL endemic areas presents a risk for nearby CL free areas. To the best of our knowledge, we report for the first time L. major infection in rodents (Rattus rattus) and L. tropica in Phlebotomus sergenti sandflies trapped in Waziristan, Pakistan.

Molecular detection of Leishmania species in human and animals from cutaneous leishmaniasis endemic areas of Waziristan, Khyber Pakhtunkhwa, Pakistan

Objectives: To detect Leishmania species in human patients, animal reservoirs and Phlebotomus sandflies in Waziristan, Pakistan. Methods: Tissue smears and aspirates from 448 cutaneous leishmaniasis (CL) suspected patients were analyzed. To sort out role of the reservoir hosts, skin scrapings, spleen and liver samples from 104 rodents were collected. Furthermore, buffy coat samples were obtained from 60 domestic animals. Sandflies were also trapped. All human, animals and sandfly samples were tested by microscopy, kinetoplastic PCR and internal transcribed spacer 1 (ITS1) PCR followed by restriction fragment length polymorphism for detection of Leishmania species. Results: An overall prevalence of 3.83% and 5.21% through microscopy and ITS1 PCR respectively was found. However, the statistically non-significant correlation was found between area, gender, and number of lesions. The presence of rodents, sandflies, domestic animals and internally displaced people increased the risk of CL. Using ITS1-PCR-RFLP, Leishmania tropica (L. tropica) was confirmed in 106 samples while 25 of the isolates were diagnosed as Leishmania major (L. major). Similarly, 3/104 rodents were positive for L. major and 14 pools of DNA samples containing Phlebotomus sergenti sandflies were positive for L. tropica. None of samples from domestic animals were positive for leishmaniasis. Conclusions: In the present study, L. tropica and L. major are found to be the main causative agents of CL in study area. Movement of internally displaced people from CL endemic areas presents a risk for nearby CL free areas. To the best of our knowledge, we report for the first time L. major infection in rodents (Rattus rattus) and L. tropica in Phlebotomus sergenti sandflies trapped in Waziristan, Pakistan.

Phase diagram of the Shastry-Sutherland Kondo lattice model with classical localized spins: a variational calculation study.

We study the Shastry-Sutherland Kondo lattice model with additional Dzyaloshinskii-Moriya (DM) interactions, exploring the possible magnetic phases in its multi-dimensional parameter space. Treating the local moments as classical spins and using a variational ansatz, we identify the parameter ranges over which various common magnetic orderings are potentially stabilized. Our results reveal that the competing interactions result in a heightened susceptibility towards a wide range of spin configurations including longitudinal ferromagnetic and antiferromagnetic order, coplanar flux configurations and most interestingly, multiple non-coplanar configurations including a novel canted-flux state as the different Hamiltonian parameters like electron density, interaction strengths and degree of frustration are varied. The non-coplanar and non-collinear magnetic ordering of localized spins behave like emergent electromagnetic fields and drive unusual transport and electronic phenomena.

First report on molecular characterization of Leishmania species from cutaneous leishmaniasis patients in southern Khyber Pakhtunkhwa province of Pakistan

OBJECTIVE@#To report presence of Leishmania major in Khyber Pakhtunkhwa of Pakistan, where cutaneous leishmaniasis (CL) is endemic and was thought to be caused by Leishmania tropica only.@*METHODS@#Biopsy samples from 432 CL suspected patients were collected from 3 southern districts of Khyber Pakhtunkhwa during years 2011-2016. Microscopy on Giemsa stained slides were done followed by amplification of the ribosomal internal transcribed spacer 1 gene.@*RESULTS@#Leishmania amastigotes were detected by microscopy in 308 of 432 samples (71.3%) while 374 out of 432 samples (86.6%) were positive by ribosomal internal transcribed spacer 1 PCR. Subsequent restriction fragment length polymorphism confirmed L. tropica in 351 and L. major in 6 biopsy samples.@*CONCLUSIONS@#This study is the first molecular characterization of Leishmania species in southern Khyber Pakhtunkhwa. It confirmed the previous assumptions that anthroponotic CL is the major CL form present in Khyber Pakhtunkhwa province. Furthermore, this is the first report of L. major from a classical anthroponotic CL endemic focus identified in rural areas of Kohat district in southern Khyber Pakhtunkhwa.

First report on molecular characterization of Leishmania species from cutaneous leishmaniasis patients in southern Khyber Pakhtunkhwa province of Pakistan

Objective To report presence of Leishmania major in Khyber Pakhtunkhwa of Pakistan, where cutaneous leishmaniasis (CL) is endemic and was thought to be caused by Leishmania tropica only. Methods Biopsy samples from 432 CL suspected patients were collected from 3 southern districts of Khyber Pakhtunkhwa during years 2011–2016. Microscopy on Giemsa stained slides were done followed by amplification of the ribosomal internal transcribed spacer 1 gene. Results Leishmania amastigotes were detected by microscopy in 308 of 432 samples (71.3%) while 374 out of 432 samples (86.6%) were positive by ribosomal internal transcribed spacer 1 PCR. Subsequent restriction fragment length polymorphism confirmed L. tropica in 351 and L. major in 6 biopsy samples. Conclusions This study is the first molecular characterization of Leishmania species in southern Khyber Pakhtunkhwa. It confirmed the previous assumptions that anthroponotic CL is the major CL form present in Khyber Pakhtunkhwa province. Furthermore, this is the first report of L. major from a classical anthroponotic CL endemic focus identified in rural areas of Kohat district in southern Khyber Pakhtunkhwa.