Assessment of Hg speciation changes in the sedimentary rock record from thermal desorption characteristics

Sedimentary mercury (Hg) has become a widely used proxy for paleo-volcanic activity. However, scavenging and drawdown of Hg by organic-matter (OM) and sulfides are important non-volcanic factors determining variability in such records. Most studies, therefore, normalize total Hg (HgT) to a Hg “host-phase” proxy (e.g., HgT/TOC for OM, HgT/TS for sulfides), with the dominant host-phase determined based on the strongest observed (linear) correlations. This approach suffers from various non-linearities in Hg-host-phase behavior and does not account for succession-level, let alone sample-level, Hg speciation changes. Thermal desorption characteristics or “profiles” (TDPs) for many Hg species during pyrolysis analysis are well-established with applications including distinguishing between OM-bound Hg and different Hg sulfides and oxides in (sub-)recent sediments. We explore the use of TDPs for geological sediment (rock) samples and illustrate the presence of multiple release phases (Hg species)—correlated to geochemical host-phase—in (almost) all the 65 analyzed Tithonian (146–145 Ma) silt and mudrock samples. By quantifying the Hg in each release phase for every sample, we find TOC concentration may determine ∼60% of the variability in the first (lower temperature) Hg TDP release phase: a stark difference with the total Hg released from these samples, where ∼20% of variation is explained by TOC variability. TDPs provide insight on sample-level Hg speciation and demonstrate that, while the common assumption of single-phase Hg speciation in sedimentary rocks is problematic, differences in Hg speciation can be detected, quantified, and accounted for using commonly applied techniques—opening potential for routine assessment

Immunological and Neurological Manifestations of COVID-19: An Intimate Relationship

Background: COVID-19 has superseded all medical scientific challenges in 2020. It presented with a range of respiratory involvement from the mild upper respiratory tract to severe pneumonia with ARDS. A percentage of these patients manifested variable neurological presentations expanding the challenges of patients’ assessment, care, and management. Objective: To discuss the neurological manifestations and the possible immunopathology of COVID-19. Methods: A literature search was performed in the PubMed database for the relevant articles published in English language between April 9th , 2020 and June 1, 2020. Few papers were extracted from Google Scholar and pre-print material as well. The keywords used to perform search included “COVID-19,” “SARS Cov2,” “neurological manifestations,” and “immunology and pathology of COVID-19”. However, animal studies were excluded in the neurological manifestations, and the final number of literature search outcome was 27 articles. Results: The immunopathology involves angiotensin-converting enzyme (ACE) receptor 2 and spike protein S1. COVID-19 has a tremendous affinity to the ACE2 receptor. The status of secondary hemophagocytic lymphohistiocytosis (sHLH) and the cytokine storm lead to different organ damage and the corresponding clinical manifestations. The documented neurological manifestations mainly include acute ischemic stroke, hemorrhagic stroke, temporal lobe, thalamic encephalitis, and one case of Guillain-Barre Syndrome, in addition to agitation, headache, and seizures. Conclusion: Although the intimate relationship between the neurons and the immune activation is the basic concept of COVID-19 immunopathology, the definite routes of entry to the neuronal cells are yet to be disclosed. Acute stroke, myositis, headache, and meningoencephalitis are the most common types of complications of COVID-19 so far

Roadway traffic sound measured up on a high-rise building - the sound-level's statistical normality

Percentile-value ceilings/thresholds have been mandated by governments around the world on roadway traffic sound-level. Such percentile values, by definition, change with the sound-level’s underlying probability distribution, i.e., the same percentile can imply different percentile values for different probability distributions. Whether the underlying probability distribution is Gaussian or not for the roadway traffic sound-level: contrary reports populate the open literature but such reports are typically weak in statistical rigor. This decades-long but ongoing debate will be surveyed comprehensively in this paper for the first time in the open literature. Then, this paper will present two new datasets measured in two separate evenings at exactly the same location up in a high-rise building, and will employ the Jarque-Bera hypothesis test to rigorously show that neither dataset is Gaussian

Visualisation of a three-dimensional (3D) object’s optimal reality in a 3D map on a mobile device

Prior research on the subject of visualisation of three-dimensional (3D) objects by coordinate systems has proved that all objects are translated so that the eye is at the origin (eye space). The multiplication of a point in eye space leads to perspective space, and dividing perspective space leads to screen space. This paper utilised these findings and investigated the key factor(s) in the visualisation of 3D objects within 3D maps on mobile devices. The motivation of the study comes from the fact that there is a disparity between 3D objects within a 3D map on a mobile device and those on other devices; this difference might undermine the capabilities of a 3D map view on a mobile device. This concern arises while interacting with a 3D map view on a mobile device. It is unclear whether an increasing number of users will be able to identify the real world as the 3D map view on a mobile device becomes more realistic. We used regression analysis intended to rigorously explain the participants’ responses and the Decision Making Trial and Evaluation Laboratory method (DEMATEL) to select the key factor(s) that caused or were affected by 3D object views. The results of regression analyses revealed that eye space, perspective space and screen space were associated with 3D viewing of 3D objects in 3D maps on mobile devices and that eye space had the strongest impact. The results of DEMATEL using its original and revised version steps showed that the prolonged viewing of 3D objects in a 3D map on mobile devices was the most important factor for eye space and a long viewing distance was the most significant factor for perspective space, while large screen size was the most important factor for screen space. In conclusion, a 3D map view on a mobile device allows for the visualisation of a more realistic environment

Numerical simulation of heat pipes in different applications

Nowadays heat pipes are considered to be popular passive heat transfer technologies due to their high thermal performance. The heat pipe is a superior heat transfer apparatus in which latent heat of vaporization is employed to transfer heat for an extended distance under a limited operating temperature difference. Numerical simulation of heat transfer devices is a principal step before implementing in real-life applications as many parameters can be tested in cost-and time-effective behaviors. The present study provides a review of the numerical simulations of various heat pipes in different applications such as cooling of electronic components, heating, ventilation, and air conditioning (HVAC), nuclear reactors, solar energy systems, electric vehicles, waste heat recovery systems, cryogenic, etc. Firstly, this work introduces a background about the main components of heat pipes such as an evacuated tube, wick, and working fluid. The fluid flow and thermal performance characteristics of heat pips are discussed, considering the optimum parameters. Finally, the critical challenges and recommendations for future work encountering the broad application of heat pipes are thoroughly studied

Optimalisasi Lahan Pekarangan Dalam Upaya Peningkatan Ketahanan Pangan Tingkat Keluarga Dengan Sistem Budidaya Tanaman Vertikultur Dan Konvensional

Permukiman di Kawasan perkotaan pada umumnya memiliki lahan pekarangan yang tidak luas rata-rata 100 m2 – 250 m2 dengan luas bangunan rata-rata 36 m2 – 100 m2. Dengan sisa luas yang masih tersedia sangat memungkinkan dimanfaatkan untuk melakukan budidaya tanaman pangan dalam pemenuhan kebutuhan sehari-sehari rumah tangga. Pembudidayaan tanaman pangan dapat dilakukan secara vertikal memanfaatkan material lokal dan bahan-bahan limbah yang tersedia. Berbagai jenis tanaman yang dapat dibudidayakan diantaranya tanaman bayam merah, patcoy, selada, kangkung darat, sawi, jahe merah, jahe biasa, temulawak, kunyit, serai, kates jepang dan kencur. Dalam meningkatkan kesuburan pertumbuhan tanaman menggunakan pupuk organik dan untuk mencegah serangan hama menggunakan pestisida nabati yang dibuat langsung menggunakan bahan-bahan alamiah. Metode yang digunakan dalam budidaya tanaman dipekarangan yaitu vertikultur dan konvensional. Metode vertikulturul yaitu dengan membuat rangka-rangka/pagar vertikal dengan penyangga berupa kolom-kolom yang dibuat dari bambu dengan jarak kolom dan tinggi rangka disesuiaikan dengan ruang yang tersedia. Wadah tanaman menggunakan botol-botol plastik air mineral dan kaleng-kaleng bekas dan diikatkan pada rangka/pagar. Sementara untuk metode konvensional dengan melakukan penanaman sistem tumpangsari yang langsung ditanam pada tanah. Pupuk dan insektisida dibuat dengan memanfaatkan bahan alamiah yang mudah diperoleh dapat berupa limbah organik dan bahan-bahan kebutuhan sehari-hari. Hasil yang diperoleh dalam pelaksanaan kegiatan yaitu masyarakat perkotaan dapat mengenal dan menerapkan system budidaya tanaman secara vertikultur dan konvensional dalam memanfaatkan ruang-ruang kosong di pekarangan. Selain itu masyarakat juga dapat membuat pupuk organik dan insektisida organik memanfaatkan bahan-bahan sehari-hari yang tersedia di rumah tangga. Sementara hasil budidaya tanaman yang dibudidayakan dimanfaatkan untuk kebutuhan bersama masyarakat setempat dan menjadi kebun percontohan

Mitigating negative impact of salinity on berseem (Trifolium alexandrinum) by foliar application of salicylic acid

Salicylic acid (SA) is a plant growth regulator known to take part in defense responses against different types of stresses, including salt stress. In this study, the role of foliar applied SA in improving the growth of berseem variety ‘Anmol’ under salt stress was examined. Plants were sown in plastic pots in the sand. Plants were treated with different concentrations of salinity (0, 60 mM and 120 mM NaCl) and salicylic acid (0, 100 mg L-1 and 150 mg L-1) was applied as a foliar spray. Salinity stress significantly reduced root and shoot fresh and dry weight, root and shoot length, photosynthetic pigments including Chl. a, b, a/b, total soluble proteins, total amino acids and uptake of K+ and Ca2+ ions in root and shoot tissues. Exogenous application of salicylic acid improved growth traits including shoot length, shoot fresh weight, root length, root fresh and weight, shoot dry weight, pigments contents (Chl. a, a/b and carotenoids). Total soluble protein and amino acid contents, activities of antioxidants peroxidase (POD), superoxide dismutase (SOD) and catalase (CAT) were also enhanced by the foliar spray of SA under saline and non-saline conditions. SA played a crucial role in lowering Na+ and Cl− ions content in shoot and root tissues while enhancing the uptake of K+ and Ca2+ ions. The study revealed that 100 mg L-1 SA treatment significantly influenced several plant parameters, including shoot length (8 cm), root length 6.7 cm, chlorophyll (1.2 mg/g FW), total soluble proteins (0.8 mg/g FW) and total amino acids (2.5 mg/g FW), SOD (1.22 U/mg protein), CAT (1.75 U/mg FW), potassium ions (29 mg/g DW), and calcium ions (43 mg/g DW) during salinity stress. Therefore, field use of SA (100 mg L-1) is recommended to enhance the growth of berseem and other fodder crops in saline soils