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The study presents integrated palynofacies, organic carbon isotope, and biomarker data to reconstruct palaeoenviromental setting for the Permian sediments (borehole MGK-6) of the Kachinapalli block of the Godavari Valley Coalfield, southern India. The palynofacies data reveal three distinct palynofacies (A–C) as follows. Palynofacies A is dominated by abundant arborescent vegetation (glossopterids and conifers) along with structured organic matter, suggesting freshwater forest swamps in proximal settings. Palynofacies B is dominated by abundant degraded organic matter and amorphous organic matter, suggesting lakeshore/flooded palaeomires in slightly dismal settings. It has a high water level in the hinterland, which enables bacterial degradation of organic matter and establishes low-oxygenation conditions within the water column. These conditions would have provided grounds for the accumulation of either degraded or amorphous organic matter. Palynofacies C is dominated by the abundance of charcoal/opaque phytoclasts, indicating prolonged transportation or post-depositional alteration, suggesting a highly-oxidizing condition in distal settings. The bulk organic δ13C range (−25.1‰ to −20.9‰) in the borehole MGK-6 is in close agreement with the global Permian records. This study also shows a weak but statistically significant correlation with the major forms of palynofacies A and C. The interlinked behaviour of bulk organic δ13C and palynofacies suggests that the changes in palaeobiogeography/palaeodepositional settings were most likely driven by the change in mean annual precipitation. The biomarker study shows the presence of n-alkane from C 15 to C 31 with unimodal and bimodal distribution patterns, revealing the source materials as vascular plants and microbially-altered organic matter. The combined palynofacies, organic carbon isotope, and biomarker data provide vital clue to salient findings for the development of environmental conditions of Godavari Valley Coalfield during lower Gondwana sedimentation. [ABSTRACT FROM AUTHOR]

Palynological data were analyzed to determine the age and depositional settings of the Jangareddygudem area in Godavari Graben, South India. The abundance of coniferous pollen grains (Araucariacites spp., Podocarpidites spp., and Callialasporites spp.) as well as pteridophytic and bryophytic trilete spore characterizes the palynofloral assemblage. The First Occurrences (FOs) of biostratigraphically significant palynomorphs taxa have been identified, which allowed us to assign the studied stratigraphic sequence to the upper Aptian–lower Albian. Recovered palynoassemblages are compared with other contemporaneous assemblages from different Gondwana continents. Palynofacies research supports hetero-lithic shelf (proximal shelf) rock formation with gradual and continuous sediment input under dysoxic to anoxic conditions. The recovered palynomorphs consistently suggest cool and humid climates during rock deposition, favoring the formation and development of a dense canopy of luxurious coniferous forests near the coast. • Palynostratigraphic studies indicated Late Aptian–Early Albian age. • Palynofacies studies indicated the existence of cool-humid conditions. • Marine palynomorphs depicted the deposition under marine settings. • Low energy environment and high influx rate has been documented. • Dysoxic–anoxic conditions are suggested in heterolithic proximal shelf of basin. [ABSTRACT FROM AUTHOR]

Abstract High responsivity UV photodetector has been realized by fabricating single crystalline epitaxial GaN-based devices grown on silicon substrate by using molecular beam epitaxy system. The influence of trap states existing within the forbidden gap on GaN-based optoelectronic devices has been investigated. The quality and performance of the fabricated GaN based UV photodetector with distinct AlN buffer layer grown at low and high substrate temperature are substantiated. A detailed analysis reveals that high temperature buffer can yield improved crystalline quality of GaN with similar morphological properties as compared to buffer layer grown at low temperature. However, the distinct buffer layer influence the optical properties as the photoluminescence analysis explains that both the films possess superior band-to-band edge emission where GaN grown with high temperature AlN buffer consists of dominant acceptor defect states in comparison to GaN with low temperature AlN buffer layer. The existence of acceptor states has been accredited by the presence of Ga vacancy related states in the band gap. The fabricated devices yield high photoresponsivity of 2.1 and 1.5 A/W at 1 V from GaN films bearing low and high accepter defect states which explain a clear correlation of device performance with trap states within the band-gap region. [ABSTRACT FROM AUTHOR]

Graphical abstract Highlights • The Callovian-Kimmeridgian age has been assigned to the Tabbowa sediments. • Palynoflora can be correlated with Murospora florida Zone of India and Australia. • Palynoflora shows close phytogeographic relationship in Middle to Late Jurassic. • Sedimentological studies directly corroborate with the palynofacies study. Abstract The palynological study of the Tabbowa sediments from Sri Lanka reveals predominant Jurassic gymnospermous pollen assemblage (Araucariacites australis , A. cooksonii , A. fissus and Callialasporites dampieri with spore Murospora florida) belongs to the Callovian-Kimmeridgian age. The collective palynoflora can be correlated to the Classopollis – Araucariacites – Shanbeipollenites assemblage zone of Africa and the Murospora florida zone of the Indian subcontinent and Australia, showing close phytogeographic relationships from the middle to late Jurassic periods. Palynofacies and sedimentological investigations inferred oxic-dysoxic conditions that prevailed when the sediments and organic matter deposited in shallow brackish water conditions in a fluvio-deltaic environment. [ABSTRACT FROM AUTHOR]

The continental sequences of Gondwana deposits from the Chintalapudi sub-basin of the Godavari Graben, South India have been palynologically investigated to explore the Permian–Triassic palynoflora. Total 11 distinct palynoassemblages belonging to the Asselian-Sakmarian (I, II), Artinskian (III, IV), Guadalupian (V, VI), Lopingian (VII, VIII, IX), Induan (X) and Olenekian (XI) age have been documented. The palynological studies support the existence of the two coal-bearing horizons in the Chintalapudi sub-basin, one in the Karharbari and Barakar formations (Sakmarian-Artinskian) while other in the Raniganj Formation (Guadalupian-Lopingian). The lack of the Upper Barakar and Barren Measures (Roadian) palynoflora indicates apparent discordance in stratigraphic sequence in this sub-basin. Presently studied the Permian-Triassic palynofloral transition has been found akin to the palynoflora of the Salt Range, Madagascar, Antarctica, Australia and South Africa. The palynofloral correlation supports the presence of Guttulapollenites palaeophytogeographic province in the Gondwana during the Guadalupian– Lopingian. The Guttulapollenites palaeophytogeographic province co-exists with the Glossopteris megafloral province and extends from the Salt Range in the north to Amery Basin in the south, Mid Zambesi-Luangwa Basin in the west to Satpura-Wardha-Godavari Basin in the east. [ABSTRACT FROM AUTHOR]

The novel coronavirus disease 2019 (COVID-19) deeply affected all forms of long-term care for older adults, highlighting infection control issues, provider and staff shortages, and other challenges. As a comparatively new, community-based long-term care option, the Program of All-Inclusive Care for the Elderly (PACE) faced unique challenges. This project investigated the impact of COVID-19 on operations in all PACE programs in one US state. Qualitative study. Structured interviews with administrators of all 12 PACE programs in North Carolina. Interviews were conducted December 2020 to January 2021 by trained interviewers over Zoom; they were transcribed, coded, and qualitatively analyzed using thematic analysis. Reported COVID-19 infection rates among PACE participants for 2020 averaged 12.3 cases, 4.6 hospitalizations, and 1.9 deaths per 100 enrollees. Six themes emerged from analyses: new, unprecedented administrative challenges; insufficient access to and integration with other health care providers; reevaluation of the core PACE model, resulting in a transition to home-based care; reorientation to be more family-focused in care provision; implementation of new, creative strategies to address participant and family psychological and social well-being in the home; and major reconfiguration of staffing, including transitions to new and different roles and a concomitant effort to provide support and relief to staff. While facing many challenges that required major changes in care provision, PACE was successful in mounting a COVID-19 response that upheld safety, promoted the physical and mental well-being of participants, and responded to the needs of family caregivers. Administrators felt that, after the pandemic, the PACE service model is likely to remain more home-based and less reliant on the day center than in the past. As a result, PACE may have changed for the better and be well-positioned to play an expanded role in our evolving long-term care system. [ABSTRACT FROM AUTHOR]

A mucocoele or extravasation of mucus is common in minor salivary glands, but unusual in major ones. Those from the submandibular gland are a diagnostic challenge and conventional management includes excision of the associated gland. We describe a 27-year-old man with a mucocoele of the submandibular gland that presented as a lateral cervical swelling and looked like a plunging ranula. The cystic lesion was completely excised and, to our knowledge, this is the first published case in which the submandibular gland was saved with no recurrence up to two years postoperatively. [ABSTRACT FROM AUTHOR]

Abstract: The evolutionary history of thecamoebians (testate amoebae) extends back to the Neoproterozoic Era. However, until now, these have had a restricted, discontinuous and modest record across the world. The studied sediment of Raniganj Formation (Godavari Graben), Andhra Pradesh, India has been assigned as Late Permian on the basis of co-occurring age-diagnostic Late Permian palynomorphs. About sixteen thecamoebian species and one taxon incertae sedis have been recorded here in the palynological slides on the basis of shell morphology and morphometry. Out of these, five belong to the family Arcellidae, seven to Centropyxidae, two to Trigonopyxidae, one to Difflugiidae, one to Plagiopyxidae, and one is regarded incertae sedis. The morphometric characteristics of fossil forms resemble their corresponding extant species studied from ecologically diverse fresh water wetlands in India. In general, the ratio of shell diameter and aperture diameter of Late Permian fossil and extant specimens show significant correlation in all the studied species. Except that, the ratio of shell length and breadth is the distinguishing feature between Centropyxis aerophila and C. aerophila ‘sylvatica’, rather than the ratio of shell length and longest diameter of the shell aperture in both fossil and extant forms. The study elucidates the minimal morphological evolution in thecamoebians and their survival during mass extinction periods and stressful environmental conditions over the geological timescale. [Copyright &y& Elsevier]

Abstract: Godavari Graben, one of the biggest basins among several Gondwana basins of India, holds a unique position not only because of its geographical location in South India, but also due to the presence of almost complete succession from Permian to Cretaceous sediments. The Graben is traversed by many small faults due to which the dating and correlation of coal bearing horizons is difficult in this area. As palynology is one of the most reliable parameter for dating, correlation and characterization of continental deposits, palynological studies have been carried out in order to date and correlate the coal bearing horizons of Gundala, Mamakannu and Kachinapalli areas from Lingala–Koyagudem coalbelt of Godavari Graben. The distributional pattern of various palynotaxa has suggested the occurrence of eight distinct palynozones in five borecores of Gundala (MLG-23, MLG-24, and MLG-28), Mamakannu (MMK-19) and Kachinapalli (MGK-6) areas. These palynozones are comparable to Talchir, Lower Karharbari, Upper Karharbari, Barakar and Raniganj palynoflora of Indian Lower Gondwana. Palynozone-1 is equivalent to Parasaccites Assemblage of Talchir Palynoflora; Palynozone-2 is correlatable with Callumispora + Parasaccites Assemblage of Lower Karharbari palynoflora; Palynozone-3 corresponds well with Parasaccites + Scheuringipollenites Assemblage of Upper Karharbari palynoflora; Palynozone-4 is comparable to Scheuringipollenites Assemblage of Barakar palynoflora; Palynozone-5 is correlatable with Faunipollenites + Striatopodocarpites Assemblage of Raniganj palynoflora; Palynozone-6 is comparable with Striasulcites Assemblage of Raniganj palynoflora; Palynozone-7 shows its equivalence with Parasaccites Assemblage of Raniganj palynoflora and Palynozone-8 corresponds well with the Crescentipollenites Assemblage of Raniganj palynoflora. On the basis of palynofloral evidences, it has been suggested that palaeoclimate during Palynozone 1–3 was cool but humidity was more in Palynozone-3 in comparison to Palynozone-2. Warmer phase started during Palynozone-4 with thick coal deposits, while Palynozones 5–8 representing Raniganj palynoflora indicate warm climate with very high humidity. [Copyright &y& Elsevier]

Due to the incessant increase in harmful electromagnetic pollution, microwave-absorbing materials (MAMs) are in great demand, and the present work is dedicated to meeting these requirements. Mg–Zr-doped Ni–Zn spinel ferrites Ni 0.6 Zn 0.4 (MgZr) x Fe 2-2 x O 4 (x = 0.05–0.20, Δ x = 0.05) have been successfully synthesized by a sol-gel citrate precursor route. The synthesized ferrites have been structurally characterized by X-ray diffraction (XRD) analysis, and their morphological structure has been confirmed by scanning electron microscopy (SEM). The complex electromagnetic parameters, determined by employing a vector network analyzer (VNA), are found to be enhanced with the addition of Mg and Zr. High dielectric and magnetic losses are observed for all of the samples. Among the various samples prepared in the series of Mg–Zr-doped Ni–Zn spinel ferrites, reflection loss (RL) as low as −35.10 dB has been obtained at a matching frequency of 10.552 GHz for the composition with x = 0.10 at a matching thickness of 4 mm. • Mg–Zr-doped Ni–Zn spinel ferrites Ni 0.6 Zn 0.4 (MgZr) x Fe 2-2 x O 4 (x = 0.05, 0.10, 0.15, 0.20) have been successfully synthesized. • Structural and electromagnetic parameters are enhanced upon doping with Mg and Zr. • A reflection loss of −35.10 dB has been achieved at a matching frequency of 10.552 GHz and a thickness of 4 mm. • The −10 dB absorption bandwidth corresponds to 2.8 GHz for the composition with x = 0.10. • The sample with x = 0.10 is best suited to serve as a microwave-absorbing material. [ABSTRACT FROM AUTHOR]

InN direct band gap semiconductor is a promising material in the nitride family for high power and high frequency optoelectronic devices. However, the reports on photo-sensing ability of the material are limited with photoresponsivity < 1 A/W only. Here, we report fast photoresponse from high quality molecular beam epitaxy grown InN islands delivering photoresponsivity of 13.5 A/W, about 30 times higher than the recently reported InN based photodetector operating in the near infrared spectral range. The ultra-broadband response with high photoresponsivity from visible to near infrared spectral range is experimentally demonstrated. To the best of our knowledge, this study presents the working of a photodetector having fast response (38 μs) and high photo detectivity (5.5 × 10 10 W -1 Hz 1/2 cm) operating at room temperature. The device yields a quiet prompt saturation and decay under periodic illumination which demonstrate excellent stability and reliability of the device with switching time. The sub-linear dependent photocurrent on the bias voltage and incident power offers good tunability for multipurpose applications. This is the first report on ultra-broadband spectral range of InN based photodetectors that open up opportunities for developing the next generation high efficiency photodetectors. [ABSTRACT FROM AUTHOR]

Current transport through a unique structure design employing high quality GaN based heterostructure with sharp interfaces has been investigated. A novel approach of structure design has been adopted to enhance the current transport in GaN heterostructures with a specific number of barrier layers of AlN which includes Single Barrier Heterostructure (SBH) and Double Barrier Heterostructure (DBH) devices. The high band gap AlN can act as a barrier for current conduction between GaN layers and help in effectively enhancing the current transport in the device through tunneling phenomena. A highly enhanced current transport in comparison with No Barrier Heterostructure (NBH) has been observed in SBH and a further improvement is perceived in DBH. Moreover, the phenomenon of current conduction is explained through drift-diffusion model, in which current enhancement upon subsequent addition of high bandgap barrier layer has resulted in localized high electric field and thus charge carrier velocity overshoots. Further, this has also been explained via quantum model, by interference of transmitted and reflected electron wave at interfaces. UV photodetectors using such heterostructure designs with and without AlN barrier layers in metal-semiconductor-metal geometry have been fabricated. The UV photodetection device developed using DBH yields photoresponsivity 80 times higher as compared to NBH device under UV illumination (325 nm). Employment of such structures will enable scaling up the production of highly efficient optoelectronic devices. [ABSTRACT FROM AUTHOR]

The present article reports electronic structure, chemical and defect states analysis of Quasi-continuous GaN film, nanoflowers decorated nanostructured GaN and nanoflowers decorated AlGaN/GaN heterostructure. The nanostructured GaN and AlGaN surfaces were decorated with nanoflowers having a size variation between 200 and 400 nm. Extensive photoemission analysis was performed to analyse surface chemistry and electronic structure and their correlation with surface morphology. Indication of free electron accumulation was perceived by the observed downwards band bending at the interface of AlGaN/GaN heterostructure. The optical response inveterate defects minimization in nanoflower decorated GaN and AlGaN/GaN heterostructure and the presence of minimum residual stress. [ABSTRACT FROM AUTHOR]

The electronic structure and surface properties of epitaxial GaN films grown on r- and a-plane sapphire substrates were probed via spectroscopic and microscopic measurements. X-ray photoemission spectroscopic (XPS) measurements were performed to analyse the surface chemistry, band bending and valence band hybridization states. It was observed that GaN/a-sapphire display a downward band bending of 0.5 eV and possess higher amount of surface oxide compared to GaN/r-sapphire. The valence band (VB) investigation revealed that the hybridization corresponds to the interactions of Ga 4s and Ga 4p orbitals with N 2p orbital, and result in N2p–Ga4p, N2p–Ga4s ∗ , mixed and N2p–Ga4s states. The energy band structure and electronic properties were measured via ultraviolet photoemission spectroscopic (UPS) experiments. The band structure analysis and electronic properties calculations divulged that the electron affinity and ionization energy of GaN/a-sapphire were 0.3 eV higher than GaN/r-sapphire film. Atomic Force Microscopic (AFM) measurements revealed faceted morphology of GaN/r-sapphire while a smooth pitted surface was observed for GaN/a-sapphire film, which is closely related to surface oxide coverage. [ABSTRACT FROM AUTHOR]

Highlights: [•] Late Permian age has been assigned to the sediments based on palynological dating. [•] Correlation with Late Permian palynoflora from other Gondwanan continents. [•] Development in a forest swamp has been deduced by palaeobotanical affinities. [•] Anaerobic reducing water logged peat-forming conditions are inferred by palynofacies analysis. [ABSTRACT FROM AUTHOR]

Abstract: The protein acetyltransferase (MTAase) function of glutamine synthetase of Mycobacterium smegmatis was established earlier. In this paper, studies were undertaken to examine MTAase function of recombinant glutamine synthetase (rGlnA1) of Mycobacterium tuberculosis, which showed >80% similarity with M. smegmatis GlnA. The specificity of MTAase to several acyl derivative of coumarins was examined. The results clearly indicated that MTAase exhibited differential specificities to several acyloxycoumarins. Further, MTAase was also found capable of transferring propionyl and butyryl groups from propoxy and butoxy derivatives of 4-methylcoumarin. These observations characterized MTAase in general as a protein acyltransferase. MTAase catalyzed acetylation of GST by 7,8-diacetoxy-4-methylcoumarin (DAMC), a model acetoxy coumarin was confirmed by MALDI-TOF-MS as well as western blot analysis using acetylated lysine polyclonal antibody. In order to validate the active site of rGlnA1 for TAase activity, effect of DAMC and L-methionine-S-sulfoximine (MSO) on GS and TAase activity of rGlnA1 were studied. The results indicated that the active sites of GS and TAase were found different. Acetyl CoA, a universal biological acetyl group donor, was also found to be a substrate for MTAase. These results appropriately characterize glutamine synthetase of Mtb exhibiting transacylase action as a moonlighting protein. [Copyright &y& Elsevier]

Abstract: A phytochemical investigation of the stems of Piper galeatum yielded one novel amide, 1-(3′-hydroxy-5′-methoxycinnamoyl)-piperidine (5) along with four known compounds, i.e. β-sitosterol (1), cyclostachine-A (2), piperine (3) and piperolein-B (4). The structures of all the five compounds, isolated for the first time from this plant were unambiguously established on the basis of their detailed spectral analysis. The structure of cyclostachine-A (2) was confirmed by X-ray crystallographic studies and structures of known compounds were confirmed by comparison of their physical and/or chemical data with those reported in the literature, which were in complete agreement. Additionally, the crude extracts as well as the isolated pure compounds were screened for their activity to inhibit TNFα (tumour necrosis factor-α)- induced expression of cell adhesion molecule ICAM-1 (intercellular adhesion molecule-1) on the surface of human umbilical vein endothelial cells (HUVECs). Among all, β-sitosterol (1) was found to be the most active compound, which was taken for further studies. β-sitosterol also significantly inhibited the TNFα-induced expression of VCAM-1 and E-selectin, which also play key role in various inflammatory diseases. The functional correlation of cell adhesion molecules inhibition was assessed by cell adhesion assay using human neutrophils. We found that β-sitosterol significantly blocks the adhesion of neutrophils to endothelial monolayer. To elucidate the molecular mechanism of inhibition of cell adhesion molecules, we investigated the status of nuclear transcription factor-κB (NF-κB) and were able to establish that β-sitosterol significantly blocked the TNFα-induced activation of NF-κB. [ABSTRACT FROM AUTHOR]