Quantification of Non-stoichiometry and Impurities in Transparent YAG Ceramics by Laser-induced Breakdown Spectroscopy (LIBS)

Transparent ceramics are an important class of optical materials with applications in street-lighting, high-strength windows, electro- and magneto-optical isolators, high-power laser gain media and nuclear radiation detectors. Compared to single-crystal growth, ceramic processing enables size scalability, near net-shape forming and prevents issues associated with dopant segregation and inhomogeneity, such as stress-induced birefringence and wavefront distortions. The fabrication of high optical grade ceramics by route of powder sintering, relies on a controlled set of techniques preventing the formation of scattering centers (pores and secondary phases) and harmful point defects (color centers, charge-carrier trapping sites). This thesis work investigates a novel approach in assisting the fabrication of yttrium aluminum garnet (YAG, Y3Al5O12) transparent ceramics, an important laser material, and minimizing the presence of these defects. As a line compound in the Al2O3-Y2O3 phase diagram, YAG has little tolerance for excess of either yttrium or aluminum oxides. What is more, the estimated compositional range of the garnet phase, (5/3-0.03) \u3c Al/Y \u3c (5/3+0.008), which is at the root of fabrication inconsistencies, challenges the sensitivity of most analytical techniques. We have evaluated the use of laser-induced breakdown spectroscopy (LIBS), a rapid, cost effective, non-destructive, and versatile technique, in the determination of stoichiometry and impurities at the various stages of the ceramic fabrication, i.e. in powders, green and sintered bodies. It was found that enough sensitivity and accuracy can be achieved on a custom-built system to discern 0.3 mole percent in the Al/Y ratio. To understand the influence of the plasma temperature on the ratio of the atomic emission lines of Al and Y species, simulations of YAG-based laser-induced plasmas were performed. The results have guided our experimental protocol by showing that above 12000 K, the Al/Y intensity ratio and thus the sensitivity of the measurement increases sharply with plasma temperature. In addition, we show that LIBS can be used to monitor the concentrations of unintentional trace impurities along those of sintering additives (SiO2) customarily used for the removal of porosity during firing. Hence, we reveal, for example, that less than 30% of SiO2 remains in the final ceramic due to evaporation during high temperature sintering. This work not only extends the range of capabilities of LIBS by showing how highly sensitive quantification of major elements can be performed in insulating materials, but also provides a new set of tools for estimating the range of solid-state solutions in advanced materials and understanding the densification of ceramics. We foresee that such capability will be invaluable for quality control purposes and in areas where fine and reproducible compositional tuning (defect engineering) is needed

The impact of therapy on the quality of life in asymptomatic patients with freshly detected hypertension

Background: Hypertension is an commonly encountered disease which adversely affect  all aspects of quality of life (QoL). The existing studies are confounded by the presence of multiple comorbidities and inclusion of elderly, which by themselves impairs the QoL. There is thus a need to study the impact of hypertension on QoL, in isolation.Method: This is a single center, prospective, intention to treat, observation study. The aim of the study is to evaluate the change in the QoL over six months, in newly diagnosed asymptomatic patients of hypertension. The tools used to assess the QoL included World Health Organisation’s Quality of Life Questionnaire (WHOQOL- BREF) and Short Form-36 (SF-36).Result: A total of 232 patients (172 males and 60 females) were enrolled in the study. The mean age was 44.66 years. A total of 102 patients (43.97%) had stage-1 and 130 patients (56.03%) had stage-2 hypertension. The female gender is associated with a higher likelihood of presentation with stage-2 hypertension. The male cohort had a better baseline QoL. The desired blood pressures was achieved in 40.52%. With therapy, the QoL improved significantly; sub-hoc analysis showed, the improvement was higher in males and those with stage-1 hypertension. There is an inverse relationship between the QoL and requirement for higher number of antihypertensive mediations.Conclusions: In patients with asymptomatic primary hypertension, treatment improves all aspects of QoL. The factors adversely affecting the QoL include female gender, higher stage of hypertension, poor blood pressure control and requirement of higher numbers of antihypertensive medicine

The existence of common fixed point theorems of generalized contractive mappings in cone metric spaces

The purpose of this paper is to the study of the existence of common fixed point theorem for a sequence of self maps satisfying generalized contractive condition for a cone metrice space and obtains some new results in it. Also the paper contains generalized fixed point theorems of [10, 13, 19] and many others from the current literature.

Unique Fixed Point Theorems for Generalized Weakly Contractive Condition in Ordered Partial Metric Spaces

The aim of this paper to prove some fixed point theorems for generalized weakly contractive condition in ordered partial metric spaces. The result extend the main theorems of Nashine and altun[17] on the class of ordered partial metric ones. Keywords: - Partial metric, ordered set, fixed point, common fixed point. AMS subject classification: - 54H25, 47H10, 54E5

ENHANCED USER PLANE SELECTION FUNCTIONALITIES IN 5G DEPLOYMENTS

Within a 3rd Generation Partnership Project (3GPP) fifth generation (5G) environment, a number of user plane challenges may arise. For example, in order to achieve minimum latency in a 5G environment, it is critical to have the same User Plane Function (UPF) for both a Serving Gateway (SGW) control plane (SGW-C) function and a packet data network (PDN) Gateway (PGW) control plane (PGW-C) function call leg. Additionally, in order to handle the scale of user plane traffic in a 5G environment, the user planes must be as efficient and as optimized as possible regarding data packet processing while at the same time the control plane also needs to establish a mobile session as quickly as possible with minimum latency. To address the type of challenges that were described above, various solutions are provided herein through several techniques. A first technique, among other things, ensures a configuration-agnostic UPF selection (which does not depend upon static configuration in multiple places) which may be performed dynamically based on UPF profiles. A second technique, among other things, not only improves upon control path session setup time by removing unwanted delays every time a handover is processed, but also uplifts the UPF processing capacity by converging different legs of the same call at the same node. Features such as these are critically important to make the 5G story a success

Aphid gene expression following polerovirus acquisition is host species dependent

Upon acquisition of persistent circulative viruses such as poleroviruses, the virus particles transcytose through membrane barriers of aphids at the midgut and salivary glands via hemolymph. Such intricate interactions can influence aphid behavior and fitness and induce associated gene expression in viruliferous aphids. Differential gene expression can be evaluated by omics approaches such as transcriptomics. Previously conducted aphid transcriptome studies used only one host species as the source of virus inoculum. Viruses typically have alternate hosts. Hence, it is not clear how alternate hosts infected with the same virus isolate alter gene expression in viruliferous vectors. To address the question, this study conducted a transcriptome analysis of viruliferous aphids that acquired the virus from different host species. A polerovirus, cotton leafroll dwarf virus (CLRDV), which induced gene expression in the cotton aphid, Aphis gossypii Glover, was assessed using four alternate hosts, viz., cotton, hibiscus, okra, and prickly sida. Among a total of 2,942 differentially expressed genes (DEGs), 750, 310, 1,193, and 689 genes were identified in A. gossypii that acquired CLRDV from infected cotton, hibiscus, okra, and prickly sida, respectively, compared with non-viruliferous aphids that developed on non-infected hosts. A higher proportion of aphid genes were overexpressed than underexpressed following CLRDV acquisition from cotton, hibiscus, and prickly sida. In contrast, more aphid genes were underexpressed than overexpressed following CLRDV acquisition from okra plants. Only four common DEGs (heat shock protein, juvenile hormone acid O-methyltransferase, and two unannotated genes) were identified among viruliferous aphids from four alternate hosts. Gene ontology (GO) enrichment analysis and Kyoto Encyclopedia of Genes and Genomes (KEGG) annotations indicated that the acquisition of CLRDV induced DEGs in aphids associated with virus infection, signal transduction, immune systems, and fitness. However, these induced changes were not consistent across four alternate hosts. These data indicate that alternate hosts could differentially influence gene expression in aphids and presumably aphid behavior and fitness despite being infected with the same virus isolate

Shisham (Dalbergia sissoo) decline by dieback disease, root pathogens and their management: a review

Shisham or sissoo (Dalbergia sissoo) is an important multipurpose tree with great economic importance, but this tree has been infected by various root pathogens. This review article shows the works conducted on root pathogens and die back disease of Shisham and their management. Around seventy-one endophytic fungus has been found in sissoo trees in Nepal. Several fungi, including, Fusarium solani, F. oxysporum, Ganoderma lucidum, Phellinus gilvus, Polypours gilvus, Rhizoctonia solani, Polyporus spongiosum, etc. cause sissoo diseases. Ganoderma Lucidum and F. Solani are two main pathogenic agents in Shisham, all of which causes root rot and vascular wilt diseases, and are the causes for the large-scale death of this tree species. Root rot ganoderma is wide spread in both natural and plant-based forests. Older trees in Shisham are usually attacked by these pathogens and cause large-scale death. However, when sissoo is grown as a re-forested pure plant without the removal of the stumps or root of the initial plant, a serious problem of root rot can develop. Field sanitation and proper management of field are necessary to control the fungal diseases of Shisham. Another deleterious disease of  Shisham is dieback disease, where sissoo plantations have been confirmed to this disease when the infected trees begin to get dry from the top. There is no suitable solution for control of dieback of Shisham. There is a need of developing resistant varieties and to improve the quality of seed. This review may be useful tool for Forest Pathologists and other persons who are working in forestry and natural conservation sectors. &nbsp

Intussusception due to non Hodgkin’s lymphoma; different experiences in two children: two case reports

In children, non-Hodgkin’s lymphoma has been found to be the lead point in intussusception involving the terminal ileum. We present here two cases of ileal primary non-Hodgkin’s lymphoma which presented as intussusception, highlighting the differing presentations of these children and their outcome, with a brief review of the literature