Influence of substitutions and Sintering Aids on Structural and Electromagnetic Properties of NiCuZn Ferrite

NiCuZn ferrite is the most important magnetic materials used for the manufacturing of multilayer chip inductors. The present work is focused on the influence of substitutions and sintering aids on electromagnetic properties of NiCuZn ferrite. (Ni0.8−xCu0.2Znx)Fe2O4 ferrites with 0.45≤x≤0.60 compositions were studied to optimize Zn concentration. The effects of Mg2+ substitution for Ni2+ and La3+, Sm3+ substitutions for Fe3+ on the electromagnetic properties of optimized NiCuZn ferrite were investigated. The effects of sintering aids like V2O5, Bi2O3 and MoO3 on the densification kinetics and electromagnetic properties of the ferrite were also investigated. Ferrite specimens were synthesized by nitrate-citrate sol-gel auto combustion process. Nanocrystalline ferrite powder was successfully synthesized by self propagating combustion method. The process resulted in the formation of nano-sized (19-22 nm), highly reactive (specific surface area- 40-50 m2/gm) and crystalline spinel ferrite powders. The ferrite powders also showed good sinterability at around <950°C. On the basis of good permeability as well as resistivity,Ni0.25Cu0.2Zn0.55)Fe2O4 composition was optimized. The composition showed, initial permeability of about 111 and the resistivity of about 8.9 MΩ-cm at 100 kHz with frequency stability up to ~10 MHz. An improved electromagnetic property of the Mg substituted ferrite was found in (Ni0.07Mg0.18Cu0.2Zn0.55)Fe2O4 nominal composition. The initial permeability, saturation magnetization and resistivity were of about 2420, 85 emu/gm and 10 MΩ- cm at 100 kHz respectively in this composition. The improved electromagnetic properties of the composition might be due to the lowering of magnetostriction constant by Mg substitution and partly due to better densification. La substitution in the ferrite mainly produced grain boundary secondary phase LaFeO3. However, bulk density and grain size of the ferrite increased with La vii substitution up to 3.75 atom%. A significant increase in initial permeability (~ 424),saturation magnetization (~ 66 emu/gm) and resistivity (~ 69 MΩ-cm at 100 kHz) was found in (Ni0.25Cu0.2Zn0.55)La0.025Fe1.975O4 composition. The increased permeability might be due to the combined effect of increased grain size, increased densification, decreased anisotropy and compressive macro-stresses, etc. The La solubility in the ferrite lattice was very low (~ 0.1 atom/unit cell). The Sm substitution showed the formation of secondary phase SmFeO3 in the ferrites. Bulk density and grain size of the ferrites increased with increasing Sm substitution up to 2.5 atom%. Electromagnetic properties were maximized in (Ni0.25Cu0.2Zn0.55)Sm0.05Fe1.95O4 composition. An initial permeability of about 312,saturation magnetization of about 70 emu/gm and resistivity of about 54 MΩ-cm at 100 kHz were measured in the composition. V2O5 exhibited better densification behavior among all sintering aids with an onset sintering temperature of ~ 825°C. The electromagnetic properties of the ferrite were also better in this V2O5 doped ferrites

Evaluation of Serum Vitamin B12 and Vitamin D Levels in Infertile Males with Suboptimal Semen Parameters- A Pilot Study from Eastern India

Introduction: According to World Health Organization (WHO), infertility is a disease defined by the inability to conceive a child after one year or more of unprotected and regular sexual intercourse. Not only female partner is responsible but male partner related factors play a crucial role in infertility. A key role of vitamin D in male reproductive organs has been suggested. Role of vitamin B12 in spermatogenesis has also been emphasised. Aim: To delineate if there is any significant association between serum vitamin B12 and vitamin D levels with semen parameters among infertile males belonging to the Eastern India. Materials and Methods: This cross-sectional study was conducted in Department of Biochemistry at Institute of Post Graduate Medical Education and Research and Seth Sukhlal Karnani Memorial Hospital, Kolkata, West Bengal, India, from May 2020 to July 2021. Fifty two infertile males of 25 to 40 years of age, with suboptimal semen parameters (semen volume, sperm count, sperm motility and sperm morphology were considered) were selected. Fasting (12 hours) blood samples were collected for estimation of serum vitamin B12 and vitamin D levels. Significance of association between each parameter with serum vitamin B12 and vitamin D levels was determined using Chi-square test and Fisher’s-exact test. Results were analysed using Statistical Package for Social Sciences (SPSS) version 25.0. A p-value less than 0.05 was considered as statistically significant. Results: Low serum vitamin D levels (<20 ng/mL) were detected in 10 (83.33% ) subjects with low semen volume and in 15 (65.21%) With low sperm count. No significant statistical association was found for vitamin D levels with semen volume and sperm count. Among subjects with abnormal sperm motility and morphology, low vitamin D levels were found in 37 (75.51%) and 16 (69.56%), respectively. A significant statistical association was found between vitamin D level and sperm motility (p-value=0.005) but not with sperm morphology. Amongst subjects with low semen volume and low sperm count, low vitamin B12 levels (<200 pg/ mL) were seen in 5 (41.6%) and 15 (65.21%), respectively. A significant statistical association was found between vitamin B12 level and sperm count (p-value=0.003). Among subjects with abnormal sperm motility and morphology, low vitamin B12 levels were present in 19 (38.77%) and 13 (56.52%) and there was a significant association between the variables p-value=0.037 and p-value=0.049, respectively. Conclusion: It can be concluded that vitamin B12 and vitamin D levels in infertile male subjects disturb normal physiological mechanisms required for being fertile. Hence, vitamin B12 and vitamin D supplementation may be suggested for improvement of semen quality

Gate-to-grave assessment of plastic from recycling to manufacturing of TENG: a comparison between India and Singapore

This study assesses the viability of recycled plastic-based triboelectric nanogenerators (TENGs) for sustainable energy harvesting in India and Singapore, concurrently examining plastic waste management. Using material flow analysis and life cycle assessment, the findings revealed that in Singapore, waste-to-energy incineration has a lower environmental impact than landfilling and mechanical recycling, attributed to natural gas usage. In India, recycling offsets impacts from incineration and landfilling, contributing to a lower net environmental impact. Economic performance of a TENG module from PET recyclates showed a 20% carbon footprint reduction when scaling up from lab to industrial “freeze-drying” processes. Key challenges in TENG manufacturing processes are also assessed for future development. This research highlights the potential of recycled plastic-based TENGs in sustainable energy and waste management

Large Mass Diphotons From Relativistic Heavy Ion Collisions

We evaluate the production of large mass diphotons from quark annihilation at BNL RHIC and CERN LHC energies from central collisions of gold nuclei. The collision is assumed to lead to either a thermally and chemically equilibrated quark gluon plasma, or a free-streaming quark gluon gas having an identical initial entropy, or a chemically equilibrating quark gluon system, with the same entropy at $T=T_c$. We also obtain an estimate of hard photon pairs from initial state quark annihilation and find that the thermal production dominates the yield up to $M \approx$ 4 GeV at RHIC, and up to 6 GeV at LHC. A simulation study of decay versus thermal diphotons is presented.Comment: Latex file; to appear in Physics Letters

Leishmania donovani Isolates with Antimony-Resistant but Not -Sensitive Phenotype Inhibit Sodium Antimony Gluconate-Induced Dendritic Cell Activation

The inability of sodium antimony gluconate (SAG)-unresponsive kala-azar patients to clear Leishmania donovani (LD) infection despite SAG therapy is partly due to an ill-defined immune-dysfunction. Since dendritic cells (DCs) typically initiate anti-leishmanial immunity, a role for DCs in aberrant LD clearance was investigated. Accordingly, regulation of SAG-induced activation of murine DCs following infection with LD isolates exhibiting two distinct phenotypes such as antimony-resistant (SbRLD) and antimony-sensitive (SbSLD) was compared in vitro. Unlike SbSLD, infection of DCs with SbRLD induced more IL-10 production and inhibited SAG-induced secretion of proinflammatory cytokines, up-regulation of co-stimulatory molecules and leishmanicidal effects. SbRLD inhibited these effects of SAG by blocking activation of PI3K/AKT and NF-κB pathways. In contrast, SbSLD failed to block activation of SAG (20 µg/ml)-induced PI3K/AKT pathway; which continued to stimulate NF-κB signaling, induce leishmanicidal effects and promote DC activation. Notably, prolonged incubation of DCs with SbSLD also inhibited SAG (20 µg/ml)-induced activation of PI3K/AKT and NF-κB pathways and leishmanicidal effects, which was restored by increasing the dose of SAG to 40 µg/ml. In contrast, SbRLD inhibited these SAG-induced events regardless of duration of DC exposure to SbRLD or dose of SAG. Interestingly, the inhibitory effects of isogenic SbSLD expressing ATP-binding cassette (ABC) transporter MRPA on SAG-induced leishmanicidal effects mimicked that of SbRLD to some extent, although antimony resistance in clinical LD isolates is known to be multifactorial. Furthermore, NF-κB was found to transcriptionally regulate expression of murine γglutamylcysteine synthetase heavy-chain (mγGCShc) gene, presumably an important regulator of antimony resistance. Importantly, SbRLD but not SbSLD blocked SAG-induced mγGCS expression in DCs by preventing NF-κB binding to the mγGCShc promoter. Our findings demonstrate that SbRLD but not SbSLD prevents SAG-induced DC activation by suppressing a PI3K-dependent NF-κB pathway and provide the evidence for differential host-pathogen interaction mediated by SbRLD and SbSLD

Systematics of Anti magnetic rotation in even-even Cd isotopes

The lifetimes for the high spin levels of the yrast band of $^{110}$Cd has been measured. The estimated B(E2) values decrease with increase in angular momentum. This is the characteristic of Anti magnetic rotation as reported in $^{106,108}$Cd. However, alignment behavior of $^{110}$Cd is completely different from its even-even neighbors. A model based on classical particle plus rotor has been used to explore the underlying systematics and develop a self consistent picture for the observed behavior of these isotopes.Comment: 18 pages including 6 figures. Accepted to be published in PLB, with some modification in the tex

Drying Shrinkage of slag blended fly ash geopolymer concrete cured at room temperature

Recent studies have shown that blending of ground granulated blast furnace slag (GGBFS) with low-calcium fly ash can have significant effects on the setting and early strength development of geopolymers cured at room temperature. This paper presents the shrinkage behaviour of geopolymer concrete mixtures in which class F fly ash was replaced with 10% or 20% GGBFS and the sodium silicate to sodium hydroxide (SS/SH) ratio was either 1.5 or 2.5. Shrinkage of 4 geopolymer and 1 ordinary Portland cement (OPC) concrete mixtures cured at room temperature were studied. Comparisons are made between the shrinkage behaviours of geopolymer concretes with different mixture proportions and those of the OPC concrete. It was found that shrinkage decreased with the increase of slag content and decrease of SS/SH ratio in geopolymer concrete cured at room temperature. The shrinkage of geopolymer concrete up to the age of 180 days was found to be comparable to that of OPC concrete of similar compressive strength. Thus, shrinkage of geopolymer concrete could be reduced to values within the limit recommended in the Australian Standards for normal OPC concrete

High-Throughput Screening for Bacterial Glycosyltransferase Inhibitors

This work is licensed under a Creative Commons Attribution 4.0 International License.The enteropathogenic and enterohemorrhagic Escherichia coli NleB proteins as well as the Salmonella enterica SseK proteins are type III secretion system effectors that function as glycosyltransferase enzymes to post-translationally modify host substrates on arginine residues. This modification is unusual because it occurs on the guanidinium groups of arginines, which are poor nucleophiles, and is distinct from the activity of the mammalian O-linked N-acetylglucosaminyltransferase. We conducted high-throughput screening assays to identify small molecules that inhibit NleB/SseK activity. Two compounds, 100066N and 102644N, both significantly inhibited NleB1, SseK1, and SseK2 activities. Addition of these compounds to cultured mammalian cells was sufficient to inhibit NleB1 glycosylation of the tumor necrosis factor receptor type 1-associated DEATH domain protein. These compounds were also capable of inhibiting Salmonella enterica strain ATCC 14028 replication in mouse macrophage-like cells. Neither inhibitor was significantly toxic to mammalian cells, nor showed in vitro cross-reactivity with the mammalian O-linked N-acetylglucosaminyltransferase. These compounds or derivatives generated from medicinal chemistry refinements may have utility as a potential alternative therapeutic strategy to antibiotics or as reagents to further the study of bacterial glycosyltransferases.National Institute of Allergy and Infectious Diseases grant number AI127973COBRE P20GM113117COBRE P20GM103638CMLD Legacy (GM111385) gran

The Versatile Approach: A Novel Single Incision Combined with Anterior and Posterior Approaches for Decompression and Instrumented Fusion to Treat Tuberculosis of the Thoracic Spine

Study DesignRetrospective case series.PurposeTo describe a novel single incision that combines anterior and posterior approaches for decompression and instrumented fusion to treat tuberculosis of the thoracic spine and study the neurological and radiological outcomes.Overview of LiteratureTuberculosis of the spine remains a major health issue in many developing countries. The options for treating tuberculosis of the thoracic spine include the anterior, posterior, and combined approaches, each with its advantages and disadvantages.MethodsTotally, 143 patients with tuberculosis of the thoracic spine were surgically treated using the “Versatile approach”. Posterior fixation was performed using sublaminar wires and a Hartshill rectangle in all patients. Anterior reconstruction was accomplished using bone graft harvested from autologous rib, iliac crest, or fibula.ResultsThe study included 45 males and 98 females, with a mean age of 33.18±18.65 years (range, 3–82 years) and a mean follow-up of 60.23±24.56 months (range, 18–156 months). Kyphosis improved from a mean value of 24.02 preoperatively to 10.25 postoperatively. A preoperative neurological deficit was observed in 131 patients, with 130 patients regaining ambulatory power. No patient had deterioration of neurological status following surgery. Fusion was achieved in all cases. The visual analogscale score improved from an average score of 7.02 preoperatively to 1.51 at final follow-up. Eight patients had superficial macerations, which healed spontaneously. One patient had buckling of the anterior graft, and one patient had implant breakage following road traffic accident.ConclusionsThe “Versatile approach” is an effective, single-stage, single-incision method that combines anterior and posterior approaches for the surgically treating tuberculosis of the thoracic spine. It offers the advantage of direct visualization for decompression and reconstruction of the anterior and posterior vertebral columns, thus providing an excellent, long-lasting clinical outcome

High-Throughput Screening for Bacterial Glycosyltransferase Inhibitors

The enteropathogenic and enterohemorrhagic Escherichia coli NleB proteins as well as the Salmonella enterica SseK proteins are type III secretion system effectors that function as glycosyltransferase enzymes to post-translationally modify host substrates on arginine residues. This modification is unusual because it occurs on the guanidinium groups of arginines, which are poor nucleophiles, and is distinct from the activity of the mammalian O-linked N-acetylglucosaminyltransferase. We conducted high-throughput screening assays to identify small molecules that inhibit NleB/SseK activity. Two compounds, 100066N and 102644N, both significantly inhibited NleB1, SseK1, and SseK2 activities. Addition of these compounds to cultured mammalian cells was sufficient to inhibit NleB1 glycosylation of the tumor necrosis factor receptor type 1-associated DEATH domain protein. These compounds were also capable of inhibiting Salmonella enterica strain ATCC 14028 replication in mouse macrophage-like cells. Neither inhibitor was significantly toxic to mammalian cells, nor showed in vitro cross-reactivity with the mammalian O-linked N-acetylglucosaminyltransferase. These compounds or derivatives generated from medicinal chemistry refinements may have utility as a potential alternative therapeutic strategy to antibiotics or as reagents to further the study of bacterial glycosyltransferases