Date palm-magnetized biochar for in-situ stabilization of toxic metals in mining-polluted soil: evaluation using single-step extraction methods and phytoavailability.

Mining activities provide a pathway for the entry and accumulation of various heavy metals in soil, which ultimately leads to severe environmental pollution. Utilization of various immobilizing agents could restore such contaminated soils. Therefore, in this study, date palm-derived biochars (BCs: produced at 300 °C, 500 °C and 700 °C) and magnetized biochars (MBCs) were employed to stabilize heavy metals (Cd, Pb, Cu and Zn) in mining polluted soil. Metal polluted soil was amended with BCs and MBCs at w/w ratio of 2% and cultivated with wheat (Triticum aestivum L.) in a greenhouse. After harvesting, dry and fresh biomass of plants were recorded. The soil and plant samples were collected, and the concentrations of heavy metals were measured after extracting with water, DTPA (diethylenetriaminepentaacetic acid), EDTA (ethylenediaminetetraacetic acid), and acetic acid. BCs and MBCs resulted in reduced metal availability and uptake, with higher fresh and dry biomass (>36%). MBCs showed maximum decrease (>70%) in uptake and shoot concentration of metals, as these reductions for Cd and Pb reached below the detection limits. Among all single-step extractions, the DTPA-extractable metals showed a significant positive correlation with shoot concentrations of tested metals. Thus, the synthesized BCs and MBCs could effectively be used for stabilizing heavy metals and improve plant productivity in multi-contaminated soils. However, future studies should focus on long term field trials to restore contaminated mining soils using modified biochars.

This study has demonstrated the performance of magnetized biochars for in-situ stabilization of toxic metals (Cd, Pb, Cu and Zn) in mining polluted soil by single extraction method. All the produced BCs and magnetized BCs showed great potential in immobilizing the metals and reducing their availability in soil, consequently decreasing their shoot concentration and plant uptake. Significant negative correlations were observed between soil pH and metal extraction from applied extraction methods such as water soluble, DTPA, and EDTA extractions. We found DTPA as a suitable extractant for investigating metal uptake in plant in multi-contaminated soils. Treatments with MBCs showed maximum decrease in plant uptake and concentration of studied metals. Thus, application of MBCs could efficiently immobilize soil heavy metals.

Potential short-term negative versus positive effects of olive mill-derived biochar on nutrient availability in a calcareous loamy sand soil.

In the present work, the olive mill solid waste (OMSW)-derived biochar (BC) was produced at various pyrolytic temperatures (300-700°C) and characterized to investigate its potential negative versus positive application effects on pH, electrical conductivity (EC), and nutrients (P, K, Na, Ca, Mg, Fe, Mn, Zn, and Cu) availability in a calcareous loamy sand soil. Therefore, a greenhouse pot experiment with maize (Zea mays L.) was conducted using treatments consisting of a control (CK), inorganic fertilizer of NPK (INF), and 1% and 3% (w/w) of OMSW-derived BCs. The results showed that BC yield, volatile matter, functional groups, and zeta potential decreased with pyrolytic temperature, whereas BC pH, EC, and its contents of ash and fixed carbon increased with pyrolytic temperature. The changes in the BC properties with increasing pyrolytic temperatures reflected on soil pH, EC and the performance of soil nutrients availability. The BC application, especially with increasing pyrolytic temperature and/or application rate, significantly increased soil pH, EC, NH4OAc-extractable K, Na, Ca, and Mg, and ammonium bicarbonate-diethylenetriaminepentaacetic acid (AB-DTPA)-extractable Fe and Zn, while AB-DTPA-extractable Mn decreased. The application of 1% and 3% BC, respectively, increased the NH4OAc-extractable K by 2.5 and 5.2-fold for BC300, by 3.2 and 8.0-fold for BC500, and by 3.3 and 8.9-fold for BC700 compared with that of untreated soil. The results also showed significant increase in shoot content of K, Na, and Zn, while there was significant decrease in shoot content of P, Ca, Mg, and Mn. Furthermore, no significant effects were observed for maize growth as a result of BC addition. In conclusion, OMSW-derived BC can potentially have positive effects on the enhancement of soil K availability and its plant content but it reduced shoot nutrients, especially for P, Ca, Mg, and Mn; therefore, application of OMSW-derived BC to calcareous soil might be restricted.

Awareness, perceptions and beliefs about physiotherapy held by physicians working in Saudi Arabia: a cross-sectional study.

[Purpose] Over the years physiotherapy has been recognized as a popular mode of treatment that decreases the disability and dependency rate of patients. However, there is still a need for its recognition in multidisciplinary health care structures. If a physician were well aware of how a physical therapist could help with treatment if patients and prevent complications, hospital patient load could be decreased to a greater extent. The aim of this study was to study the awareness, perception and beliefs of physicians working in Saudi Arabia about physiotherapy. [Subjects and Methods] Three hundred fifteen members of the Saudi Commission for Health Specialties (SCFHS) with different specialties, nationalities, designation, and work experience, working in various hospitals in 5 regions of Saudi Arabia were invited to participate in this study. A 22-item questionnaire was used for data collection including sections on physicians' demographics, educational levels and knowledge about physiotherapy. [Results] After applying the inclusion and exclusion criteria, data from 280 respondents was used for analysis. Seventy-five percent of respondents reported to having some knowledge of physiotherapy, and 11% of them referred patients to physiotherapy departments regularly, while 14% referred patients occasionally. To the best of our knowledge, this is first study performed in Saudi Arabia to evaluate awareness of physicians about the physiotherapy profession. [Conclusion] The results of this study highlight the need to organize various workshops and lectures about the effectiveness of physiotherapy in various diseases for physicians, on a regular basis, to update them with evidence-based treatment. It is the responsibility of physical therapists to raise the perceptions of other healthcare professionals about their profession.

Amnesia due to fornix infarction.

Background and Purpose-The fornix connects various structures involved in memory. We report a patient with anterograde amnesia after an acute ischemic infarct in the anterior fornix. Case Description-A 71-year-old female with acute-onset amnesia had neuroimaging studies showing ischemic infarction of both columns and the body of the fornix and the genu of the corpus callosum. Neuropsychological evaluation revealed anterograde amnesia without evidence of callosal disconnection. The patient showed marked improvement in her memory function on the follow-up visit. Conclusions-Amnesia in this case is likely due to infarction of the anterior fornix structures.