Gradual Evolution Research Articles

PSR J0026−1955: A curious case of evolutionary subpulse drifting and nulling

ABSTRACT PSR J0026−1955 was independently discovered by the Murchison Widefield Array recently. The pulsar exhibits subpulse drifting, where the radio emission from a pulsar appears to drift in spin phase within the main pulse profile, and nulling, where the emission ceases briefly. The pulsar showcases a curious case of drift rate evolution as it exhibits rapid changes between the drift modes and a gradual evolution in the drift rate within a mode. Here, we report new analysis and results from observations of J0026−1955 made with the upgraded Giant Metrewave Radio Telescope at 300–500 MHz. We identify two distinct subpulse drifting modes: A and B, with mode A subcategorized into A0, A1, and A2, depending upon the drift rate evolutionary behaviour. Additionally, the pulsar exhibits short and long nulls, with an estimated overall nulling fraction of ∼58 per cent, which is lower than the previously reported value. Our results also provide evidence of subpulse memory across nulls and a consistent behaviour where mode A2 is often followed by a null. We investigate the drift rate modulations of J0026−1955 and put forward two different models to explain the observed drifting behaviour. We suggest that either a change in polar gap screening or a slow relaxation in the spark configuration could possibly drive the evolution in drift rates. J0026−1955 belongs to a rare subset of pulsars which exhibit subpulse drifting, nulling, mode changing, and drift rate evolution. It is therefore an ideal test bed for carousel models and to uncover the intricacies of pulsar emission physics.

Urban expansion of Korhogo City (Côte d’Ivoire) using gis and nocturnal remote sensing

Temporal data series of stable Artificial Lights At Night (ALAN) obtained from sources such as DMSP/OLS and VIIRS/DNB provide valuable insights into the dynamics of urban expansion. This study introduces a novel methodology for characterizing urban boundaries, which combines textural analysis utilizing the Co-occurrence matrix and urban surface delineation employing the Wombling contour detection algorithm. Applying this method to the city of Korhogo in northern Côte d'Ivoire, the findings reveal an irregular and gradual evolution of urban surfaces between 1992 and 2012, with a rate of change of 35 km2. However, starting from 2012, a rapid urbanization process is observed, continuing until 2020, characterized by an evolution rate of approximately 45 km2. Considering the significant urban expansion witnessed in the city of Korhogo, it is imperative to implement appropriate urban management strategies and measures for ecosystem protection.

The evolution of global cross-border R&D investment: A network analysis integrating geographical thinking

As one of the manifestations of economic globalization, cross-border research and development (R&D) investment of multinational enterprises (MNEs) has become an important way for innovation resources to flow in the world and constitute a worldwide R&D network. The country's position within the network has undergone a gradual evolution, but fewer studies have concentrated on the alterations to the network structure they have brought about and the factors affecting them. Our study of global cross-border R&D investment sheds light on the interactions of the global network within its singular context of country-level determinants, its internal network structure and geographical patterns. The findings suggest that global cross-border R&D investment has formed a stable geographical distribution pattern, and a complete but heterogeneous network structure, including a hierarchical structure and a core-periphery structure, while country features such as technological strength, skill levels, market potential, and economic development not only set the pace of cross-border R&D investment, but that they also influence both the network structure and the power positions of each node. Implications are discussed.

Structures and stabilities of UPbn (n ≤ 18) clusters: A first-principles global optimization calculation

Endohedrally doped clusters have received much attention because they can act as superatoms and have great potential as the building blocks for cluster-assembled materials. We have carried out a comprehensive study based on the combination of the particle swarming optimization algorithm and the relativistic density functional theory, to obtain geometric structures and stabilities of lead (Pb) clusters doped with one uranium (U) atom. A gradual evolution pattern was observed with the increasing number of Pb atoms, from exohedrally doped structures to quasi-endohedral structures, and finally to endohedrally doped structures. At least 12 and 11 Pb atoms were necessary to encapsulate the U atom completely in the calculation without and with the spin-orbit coupling (SOC) effect respectively. The UPb16 cluster was represented as a highly stable endohedral cage structure with the U atom around its center. In addition, the crucial role of the SOC effect was emphasized. We hope that our findings will provide a fundamental understanding of actinide-doped lead clusters, which may be quite different from their light element analogues.

Elucidating Individual Magnetic Contributions in Bi-Magnetic Fe3 O4 /Mn3 O4 Core/Shell Nanoparticles by Polarized Powder Neutron Diffraction.

Heterogeneous bi-magnetic nanostructured systems have had a sustained interest during the last decades owing to their unique magnetic properties and the wide range of derived potential applications. However, elucidating the details of their magnetic properties can be rather complex. Here, a comprehensive study of Fe3 O4 /Mn3 O4 core/shell nanoparticles using polarized neutron powder diffraction, which allows disentangling the magnetic contributions of each of the components, is presented. The results show that while at low fields the Fe3 O4 and Mn3 O4 magnetic moments averaged over the unit cell are antiferromagnetically coupled, at high fields, they orient parallel to each other. This magnetic reorientation of the Mn3 O4 shell moments is associated with a gradual evolution with the applied field of the local magnetic susceptibility from anisotropic to isotropic. Additionally, the magnetic coherence length of the Fe3 O4 cores shows some unusual field dependence due to the competition between the antiferromagnetic interface interaction and the Zeeman energies. The results demonstrate the great potential of the quantitative analysis of polarized neutron powder diffraction for the study of complex multiphase magnetic materials.

Hope and Despair: Understanding Change in Turkey-EU Relations

Joining the European Union has been a long-lasting priority in Turkish foreign policy and one which has fluctuated from relatively short episodes of hope to longer periods of frustration or even despair. The article reviews the intensity, drivers and justification of change during five critical periods: the 1959 application for association that led to the signature in 1963 of the Treaty of Ankara; the request for full membership in 1987 that led to the signature of the Customs Union in 1995; the Helsinki decision in 1999 to grant Turkey candidate status; the unenthusiastic opening of the accession negotiations in 2005; and the gradual evolution toward a transactional cooperation ever since, which coexists with signs of an increasingly adversarial relationship. Foreign policy changes in Turkey are one of the factors explaining the evolution of this relationship. This article emphasizes the need to take into consideration foreign policy changes in the EU and within some of its member states, as well as global and regional transformations. It also points out the extraordinary resilience of EU-Turkey relations, and how pragmatic, ideational and normative arguments have so far contributed to avoidance of an abrupt divorce.

High-pressure-induced electronic and structural transition of superatoms.

High pressure has been recognized as an important tool in molecule and materials research, and thus, it is expected to be used to understand the evolution of electronic states and geometric structures in superatoms. In this work, by studying three characteristic axial compressions on a typical endohedral metallofullerene superatom U@C28 with Td symmetry, we find that the triplet ground electronic state is preserved when the compression moves along the direction that reduces the symmetry to D2d, but the electronic state of the structure compressed along the direction of symmetry reduction to C2v or Cs is transformed into a singlet. The transition is attributed to the distinction in the response of electron spin to different axial compressions, which results in a change in the electron occupation mode of the system. Furthermore, we also confirm the gradual evolution from stereo to near-plane superatoms and the connection between their electron structures. This is reflected in the fact that the electron density distributions of the superatomic molecular orbitals (SAMOs) with extension along the restricted degrees of freedom (Dz2, Fz3 SAMOs) gradually contract, and the delocalization destruction of special orbitals is associated with this freedom. In addition, Raman and ultraviolet-visible spectra show a hyperchromic effect and redshift of characteristic peaks during axial compression, which are expected to be used for fingerprinting the superatomic planarization. Therefore, our work provides new insights based on high pressure for future research toward the discovery of physical properties and applications of superatoms.

Design and development of SS316L-IN718 functionally graded materials via laser powder bed fusion

In this study, the capability of the standard laser powder bed fusion process for the fabrication of SS316L-IN718 functionally graded materials with different designs was investigated. In addition to the successful demonstration of producing dense parts with minimal defects, the gradual evolution of the solidification structure from cellular to the dendritic, the smooth distribution of constituent elements, and the orientation and grain growth in the build direction were analyzed and discussed. Finally, we report that the gradient design with a 50 wt% mixed intermediate zone and optimum processing condition showed the best mechanical properties with a tensile strength of about 610 MPa and 31.5 % total elongation.

Multiple ridge subduction processes in the southern Altaids: Implications from clinopyroxene chemistry and Sr–Nd–Hf isotopes of late carboniferous Nb-enriched, magnesian diorite-andesites in West Junggar, NW China

Magnesian (Mg# > 45) and/or Nb-rich (Nb > 6 ppm) dioritic-andesitic rocks have been identified in the Mayile area of southern West Junggar, Northwest China. A systematic petrological, geochronological, whole-rock geochemical, Sr–Nd–Hf isotope, and clinopyroxene chemistry study was conducted to constrain the petrogenesis, mantle source, and P–T conditions of magmas as well as the tectonomagmatic processes in the southern Paleo-Asian Ocean subduction zone. Mayile dioritic-andesitic rocks generated in the Late Carboniferous (306–312 Ma) have a high SiO2 content (52.3–63.2 wt%) and high Mg# (46–66) as well as sanukitic-like low LaN/YbN and Sr/Y ratios. They have high Nb contents (6.27–11.6 ppm) and Nb/U (9–18) ratios and are Nb-enriched sanukitic high-Mg andesites (HMAs). Clinopyroxene thermobarometry indicates that the parental magma of the Mayile HMAs experienced a high-temperature (1137–1199 °C) and shallow-level (0.8–0.17 GPa) partial melting in a mantle wedge. They have εNd(t) (+5.14 to +6.42), εHf(t) (+8.8 to +14.4), and zircon εHf(t) (+9.4 to +15.8) values and a slightly high (87Sr/86Sr)t ratio ranging from 0.703214 to 0.704140 relative to normal mid-ocean ridge basalt (N-MORB). The results suggest that West Junggar was dominated by continuous records of sanukitic rocks hinting at multiple ridge subduction processes in the southern Altaids. We reconstructed the subduction history of the Junggar Ocean in the Carboniferous-Permian from these particular observations in West Junggar, and gained insight into the gradual evolution of the tectonic setting, which transitioned from normal intraoceanic subduction to hot subduction of the young oceanic lithosphere from the Early to Late Carboniferous, with subsequent ridge subduction occurring mainly in the Late Carboniferous.

Genomic characteristics of a novel emerging PRRSV branch in sublineage 8.7 in China.

Porcine reproductive and respiratory syndrome virus (PRRSV) has caused serious economic losses to the pig industry worldwide. During the continuous monitoring of PRRSV, a new PRRSV strain type with novel characteristics was first identified in three different regions of Shandong Province. These strains presented a novel deletion pattern (1 + 8 + 1) in the NSP2 region and belonged to a new branch in sublineage 8.7 based on the ORF5 gene phylogenetic tree. To further study the genomic characteristics of the new-branch PRRSV, we selected a sample from each of the three farms for whole-genome sequencing and sequence analysis. Based on the phylogenetic analysis of the whole genome, these strains formed a new independent branch in sublineage 8.7, which showed a close relationship with HP-PRRSV and intermediate PRRSV according to nucleotide and amino acid homology but displayed a completely different deletion pattern in NSP2. Recombinant analysis showed that these strains presented similar recombination patterns, all of which involved recombination with QYYZ in the ORF3 region. Furthermore, we found that the new-branch PRRSV retained highly consistent nucleotides at positions 117-120 (AGTA) of a quite conserved motif in the 3'-UTR; showed similar deletion patterns in the 5'-UTR, 3'-UTR and NSP2; retained characteristics consistent with intermediate PRRSV and exhibited a gradual evolution trend. The above results showed that the new-branch PRRSV strains may have the same origin and be similar to HP-PPRSV also evolved from intermediate PRRSV, but are distinct strains that evolved simultaneously with HP-PRRSV. They persist in some parts of China through rapid evolution, recombine with other strains and have the potential to become epidemic strains. The monitoring and biological characteristics of these strains should be further studied.

INTEGRATION OF TERRESTRIAL LASER SCANNING AND SMARTPHONE LIDAR: THE CASE STUDY OF LIDZBARK CASTLE

Abstract. In many cases, archaeological research allows to explain the history and evolution of heritage buildings. To support these studies, the availability of reliable 3D representations of such buildings has already been shown to be of remarkable importance. Thanks to the development of Terrestrial Laser Scanning (TLS) and close-range photogrammetric techniques, the generation of such 3D representations by means of remote sensing techniques has become quite common nowadays. While TLS can still be considered as the state-of-the-art method for generating accurate building geometric models, acquisition methods based on the use of mobile devices is becoming a quite attractive solution in order to speed up the survey while also enabling an easier data acquisition on certain narrow places. Despite a plethora of mobile mapping tools is currently available on the market, smartphones are clearly the most widely used smart mobile device in the world, being an ideal solution in terms of usability, portability, and spread. Motivated by this observation and by the recent availability of smartphones provided with Light Detection and Ranging (LiDAR) sensors, this paper aims at investigating the effectiveness of the integration of traditional TLS with smartphone LiDAR on the survey of the castle in Lidzbark Warminski, which dates back to the mid-fourteenth century. TLS, with the scanner set on a standard tripod, was used to scan easily accessible places. TLS mounted on a dedicated tripod, patented by the co-authors of the project was used for less easy-to-reach places. Finally, smartphone LiDAR enabled 3D data acquisition on very hard-to-reach locations, e.g. excavation areas. The model obtained by integrating the data acquired by all the considered methods allowed to properly describe all the area of interest of the castle, being usable for the technical documentation of such historic building. The obtained model significantly advanced the state of knowledge about the castle in Lidzbark Warminski. As a result of the work, many traces of the history of the complex were discovered, proving its gradual evolution.

An Overview of 10 Years of Activity of a Molecular Laboratory for Buruli Ulcer Diagnosis at a Field Hospital in Benin.

Buruli ulcer (BU) is a neglected tropical disease caused by Mycobacterium ulcerans. Early diagnosis is crucial to prevent morbidity. In November 2012, a field laboratory fully equipped for the rapid on-site quantitative PCR (qPCR) diagnosis of M. ulcerans was established at the Buruli ulcer treatment center (CDTLUB) center in Pobè Benin, a region where BU is endemic. We describe its first 10 years of activity and its gradual evolution into an expert laboratory for BU diagnosis. From 2012 to 2022, the laboratory analyzed 3,018 samples from patients attending consultations for suspected BU at the CDTLUB in Pobè. Ziehl-Neelsen staining and qPCR targeting the IS2404 sequence were performed. Since 2019, the laboratory has also received and analyzed 570 samples from other centers. The laboratory confirmed the diagnosis of BU by qPCR for 39.7% samples: M. ulcerans DNA was detected in 34.7% of swabs, 47.2% of all fine needle aspiration samples (FNA) and 44.6% of all skin biopsy specimens. Positive Ziehl-Neelsen staining results were obtained for 19.0% samples. Bacterial load, estimated by qPCR, was significantly greater for the Ziehl-Neelsen-positive samples than for Ziehl-Neelsen-negative samples, and detection rates were highest for FNA samples. Overall, 26.3% of the samples received from other centers were positive for BU. Most of these samples were sent by the CDTLUBs of Lalo, Allada, and Zagnanado, Benin. The establishment of the laboratory in the CDTLUB of Pobè has been a huge success. Optimal patient care depends on the close proximity of a molecular biology structure to BU treatment centers. Finally, FNA should be promoted among caregivers. IMPORTANCE Here, we describe the first 10 years of activity at a field laboratory established at the Buruli ulcer treatment center (CDTLUB) in Pobè, Benin, a country in which Mycobacterium ulcerans is endemic. Between 2012 and 2022, the laboratory analyzed 3,018 samples from patients consulting the CDTLUB of Pobè with a suspected clinical BU. Ziehl-Neelsen staining and qPCR targeting the IS2404 sequence were performed. In total, 39.7% of samples tested positive by qPCR and 19.0% tested positive by Ziehl-Neelsen staining. Detection rates were highest for FNA samples, and the bacterial loads estimated by qPCR were significantly higher for Ziehl-Neelsen-positive samples than for Ziehl-Neelsen-negative samples. Since 2019, the laboratory has also analyzed 570 samples received from outside the CDTLUB of Pobè, 26.3% of which were positive for BU. Most of these samples were sent by the CDTLUBs of Lalo, Allada, and Zagnanado in Benin. The establishment of the laboratory in the CDTLUB of Pobè has been a huge success, with major benefits for both the medical staff and patients. Our findings illustrate that the usefulness and feasibility of having a diagnostic center in rural Africa, where the disease is endemic, is a key part of optimal patient care, and that FNA should be promoted to increase detection rates.

Medical image categorization combining image segmentation and machine learning

The death rate has increased in recent years due to the rising prevalence of encephaloma tumors across all age brackets. Because of their complex structure and background noise, tumors are difficult to detect in medical imaging and require a great deal of time and effort on the part of professionals. This is crucial since locating the tumor early on is key to successful treatment. Scans can detect and even forecast the presence of cancer at a variety of stages. A combination of these scans with segmentation and relegation techniques can aid in a rapid diagnosis, saving valuable time for the treating physician. Due to the complex nature of tumors and the gradual evolution of noise in MR imaging data, physical tumor identification has become a complicated and time-consuming process for medical professionals. Hence, early detection and localization of the tumor site is essential. Using segmentation and relegation techniques, medical imaging can pinpoint cancer tumors at multiple stages for a precise diagnosis. This study presents a machine learning-based method for automatically segmenting and labelling MRI scans of the brain to help in the detection of malignant growths. In addition, this framework employs a number of machine learning algorithms for tasks including image pre-processing, segmentation, feature extraction, and classification, including Nave Bayes, Nearest Neighbours, and Decision Table.

Spin excitation continuum to topological magnon crossover and thermal Hall conductivity in Kitaev magnets

There has been great interest in identifying a Kitaev quantum spin liquid state in frustrated magnets with bond-dependent interactions. In particular, the experimental report of a half-quantized thermal Hall conductivity in $\alpha$-RuCl$_3$ in the presence of a magnetic field has generated excitement as it could be strong evidence for a field-induced chiral spin liquid. More recent experiments, however, provide a conflicting interpretation advocating for topological magnons in the field-polarized state as the origin of the non-quantized thermal Hall conductivity observed in their experiments. An inherent difficulty in distinguishing between the two scenarios is the phase transition between a putative two-dimensional spin liquid and the field-polarized state exists only at zero temperature, while the behaviour at finite temperature is mostly crossover phenomena. In this work, we provide insights into the finite temperature crossover behavior between the spin excitation continuum in a quantum spin liquid and topological magnons in the field-polarized state in three different theoretical models with large Kitaev interactions. These models allow for a field-induced phase transition from a spin liquid (or an intermediate field-induced spin liquid) to the field-polarized state in the quantum model. We obtain the dynamical spin structure factor as a function of magnetic field using molecular dynamics simulations and compute thermal Hall conductivity in the field-polarized regime. We demonstrate the gradual evolution of the dynamical spin structure factor exhibiting crossover behaviour near magnetic fields where zero-temperature phase transitions occur in the quantum model. We also examine nonlinear effects on topological magnons and the validity of thermal Hall conductivity computed using linear spin wave theory. We discuss the implications of our results to existing and future experiments.

Eurooptimism and Euroscepticism on the Example of the British Labour Party, Liberal Democrats and Scottish National Party

In this article, the three British parties in terms of their attitudes towards the EU are analysed. British parties are not homogenous with no single position on Europe being dominant. Nevertheless, there has been a rise of Euroscepticism across all political parties regardless of their affiliation in the recent years. Brexit referendum has become a ‘point of no return’ since no political force in Britain has questioned British exit from the EU and its results. The debate has switched to the conditions on which the post-Brexit UK collaborates with the EU but there is no discussion whether Britain needs to return to the EU. It is a question of whether British interests have been taken into account and how close the relationship with the Europeans should be. The research reflects gradual evolution of the three British parties (Labour Party, the Liberal Democrats, and the Scottish National Party) and their attitudes towards European integration. It is shown that the Labour Party and the Liberal Democrats had a U-turn on key policies such as free movement of people or joining the Eurozone whereas the Scottish National Party reinvented itself and became a proponent of the European integration (with some reservations). The author tries to answer the question of whether the above parties could have prevented Brexit.

Surfacing woman-consciousness in Reza de Wet’s On the Lake

Reza de Wet is one of South Africa’s most acclaimed and translated playwrights. On the Lake is one of her most under-researched plays. It forms part of a trilogy of Chekhov-sequels all of which premiered in South Africa before they were eventually published by the Brittain based Oberon Books in 2002 as A Russian Trilogy, thereby reconsolidating De Wet’s international stature. On the Lake’s Chekhovian source text is The Seagull. De Wet crops Chekhov’s dozen-plus cast of characters to five, restricting them to female characters, all contained in the framing perspective of a protagonist-cum-centre-of-consciousness, underlining as such her surfacing of Chekhov’s concern with throttled female artistic agency. On the Lake is discussed here as De Wet’s dramatization of the co-incidence and correlation of a woman’s artistic awakening with psycho-sexual emancipation amidst and at odds with a patriarchal regime. De Wet recasts The Seagull’s Nina Mikhailovna Zaryechnaia as the protagonist in On the Lake and dramatizes her gradual evolution from an actress into a playwright and her shedding of her emotional dependence on her former lovers. On the Lake is read in comparison with an unpublished draft of it that offers insight into De Wet’s writing process and the motivations underlying the final published version. I make a case for De Wet’s optimism regarding the artistic and psychological self-actualization that her protagonist achieves. In view of De Wet’s resistance to the moniker feminism, Curb’s term woman-conscious theatre is engaged to place De Wet’s project in a wider field of woman-centred drama.

Emergence of Dynamically-Disordered Phases During Fast Oxygen Deintercalation Reaction of Layered Perovskite.

Determination of a reaction pathway is an important issue for the optimization of reactions. However, reactions in solid-state compounds have remained poorly understood because of their complexity and technical limitations. Here, using state-of-the-art high-speed time-resolved synchrotron X-ray techniques, the topochemical solid-gas reduction mechanisms in layered perovskite Sr3 Fe2 O7- δ (from δ ∼ 0.4 to δ = 1.0), which is promising for an environmental catalyst material is revealed. Pristine Sr3 Fe2 O7- δ shows a gradual single-phase structural evolution during reduction, indicating that the reaction continuously proceeds through thermodynamically stable phases. In contrast, a nonequilibrium dynamically-disordered phase emerges a few seconds before a first-order transition during the reduction of a Pd-loaded sample. This drastic change in the reaction pathway can be explained by a change in the rate-determining step. The synchrotron X-ray technique can be applied to various solid-gas reactions and provides an opportunity for gaining a better understanding and optimizing reactions in solid-state compounds.

Epigenetic Modifications in Prostate Cancer Metastasis and Microenvironment

The gradual evolution of prostate tissue from benign tumor to malignant lesion or distant metastasis is driven by intracellular epigenetic changes and the tumor microenvironment remodeling. With the continuous study of epigenetic modifications, these tumor-driving forces are being discovered and are providing new treatments for cancer. Here we introduce the classification of epigenetic modification and highlight the role of epigenetic modification in tumor remodeling and communication of the tumor microenvironment.

Gradual evolution of hydrogen-bonding patterns with the carbamoylcyanonitrosomethanide anion in a series of aliphatic diammonium salts.

Developing the structures of organic materials that rely on the hydrogen bonding of multifunctional substrates is often complicated due to a competition between various possible motifs. In this context, the illustrative case of the carbamoylcyanonitrosomethanide anion, [ONC(CN)-C(O)NH2]-, suggests sufficient control over the crystal lattice with a set of supramolecular synthons, which are specific to all the present nitroso, carbamoyl and cyano groups. The structures of the carbamoylcyanonitrosomethanide salts of ethane-1,2-diammonium, C2H10N22+·2C3H2N3O2-, (1), piperazine-1,4-diium, C4H12N22+·2C3H2N3O2-, (2), butane-1,4-diammonium, C4H14N22+·2C3H2N3O2-, (3), and hexane-1,6-diammonium, C6H18N22+·2C3H2N3O2-, (4), reveal two- and three-dimensional hydrogen-bonded frameworks governed by a set of site-selective interactions. The strongest N-H...O hydrogen bonds [N...O= 2.6842 (17)-2.8718 (17) Å, mean 2.776 (2) Å] are associated with the polarized ammonium N-H donors and nitroso O-atom acceptors, which sustain invariant motifs in the form of nitroso/ammonium dimers. Subtle structural changes within this series of compounds concern the rupture of some weaker interactions, i.e. mutual hydrogen bonds of the carbamoyl groups in (1)-(3) [N...O= 2.910 (2)-2.9909 (18) Å; mean 2.950 (2) Å] and carbamoyl/nitrile hydrogen bonds in (1), (2) and (4) [N...N= 2.936 (2)-3.003 (3) Å, mean 2.977 (2) Å], providing a gradual evolution of the hydrogen-bonding pattern. A hierarchy of the synthons involving three different groups could be applicable to supramolecular synthesis with polyfunctional methanide species, suggesting also a degree of control over layered and interpenetrated hydrogen-bonded networks.

Primary Myelofibrosis with Extramedullary Hematopoiesis – A Case Report with a Review of Literature

Primary myelofibrosis (PMF) is the least common of all myeloproliferative neoplasms (MPNs), characterized by a neoplastic transformation of early hematopoietic stem cells, predominantly megakaryocytes and granulocytes. The disease shows gradual evolution from an initial prefibrotic stage to an overt fibrotic stage. Janus kinase (JAK) 2, CALR, and MPL mutations are most common in nonchronic myeloid leukemia MPNs but are not always present. Ineffective marrow hematopoiesis leads to extramedullary hematopoiesis and associated symptoms such as splenomegaly, hepatomegaly, anemia, and pro-inflammatory cytokines-induced constitutional symptoms. The WHO criteria, 2016, consider the combination of clinical, morphological, and molecular genetics features for the diagnosis of the condition. Currently, Dynamic International Prognostic Scoring System is most widely used to predict the prognosis. Here, we report the case of a 63-year-old male diagnosed with the rare disease PMF with extramedullary hematopoiesis and bleeding gastric varices. PMF was diagnosed by bone marrow biopsy showing diffuse fibrosis, positive JAK2-V617F mutation in genetic analysis, negative Philadelphia chromosome, pancytopenia, splenomegaly, and raised leukocyte dehydrogenase.