Frustrated spin ladder with alternating spin-1 and spin-1/2 rungs

We study the impact of the diagonal frustrating couplings on the quantum phase diagram of a two-leg ladder composed of alternating spin-1 and spin-1/2 rungs. As the coupling strength is increased the system successively exhibits two gapped paramagnetic phases (a rung-singlet and a Haldane-like non-degenerate states) and two ferrimagnetic phases with different ferromagnetic moments per rung. The first two states are similar to the phases studied in the frustrated spin-1/2 ladder, whereas the magnetic phases appear as a result of the mixed-spin structure of the model. A detailed characterization of these phases is presented using density-matrix renormalization-group calculations, exact diagonalizations of periodic clusters, and an effective Hamiltonian approach inspired by the analysis of numerical data. The present theoretical study was motivated by the recent synthesis of the quasi-one-dimensional ferrimagnetic material Fe$^{II}$Fe$^{III}$ (trans-1,4-cyclohexanedicarboxylate) exhibiting a similar ladder structure.Comment: 10 pages, 8 figure

Antiferromagnetic sawtooth chain with spin-½ and spin-1 sites

We study the low-energy properties of a sawtooth chain with spin-1's at the bases of the triangles and spin-½'s at the vertices of the triangles. The spins have Heisenberg antiferromagnetic interactions between nearest neighbors, with a coupling J2 between a spin-1 and a spin-½, and a coupling J1=1 between two spin-1's. Analysis of the exact diagonalization data for periodic chains containing up to N=12 unit cells shows that the ground state is a singlet for exchange couplings up to approximately J2=3.8, whereas for larger J2 the system exhibits a ferrimagnetic ground state characterized by a net ferromagnetic moment per unit cell of ½. In the region of small interactions J2, the mixed spin sawtooth chain maps on to an effective isotropic spin model representing two weakly interacting and frustrated spin-½ Heisenberg chains composed of spin-½ sites at odd and even vertices, respectively. Finally, we study the phenomenon of a macroscopic magnetization jump which occurs if a magnetic field is applied with a value close to the saturation field for J2=2

Strategies Towards the Synthesis of Staurosporine Indolocarbazole Alkaloid and Its Analogues

In this Chapter we revisit the main strategies used for years in synthesizing staurosporine indolocarbazole alkaloid and its analogues, which are promising compounds for treating cancer. In addition to describing the details of the synthesis strategies, including the key challenges that had to be faced, we offer a historical perspective of the development in the field

Analgesic and anti-inflammatory properties of the aqueous extract leaves of Murraya koenigii linn in small animal models

Background: The present study was carried out to evaluate the analgesic activity of aqueous extract leaves of Murraya koenigii linn in Albino rats using tail flick method, Eddy’s hot plate methods and anti-inflammatory activity in Carrageenan induced paw edema in rats.Methods: The analgesic activity was evaluated using Eddy’s hot plate induced hyperalgesia and tail flick method, which served as thermal induced pain, where the animal were placed on the hot plate and the reaction time to (lick the paw/jump out) from the hot plate was observed, 0, 30, 60, 90 mins. Murraya 300 mg, 600 mg/kg/body weight (BW) and ibuprofen (5 mg/kg BW) was administered per oral. The anti-inflammatory activity was measured by Carrageenan induced paw edema volumes at 0, 1, 2, 3 and 4 hrs using mercury plethysmometer, which served as chemical induced pain models.Results:  The mean reaction time in Murraya at a dose of 600 mg/kg at 0 min 5.45±0.72, at 30 mins 6.52±1.03, at 60 mins 7.6±0.81, at 90 mins 8.8±0.63 respectively. The mean reaction time increased significantly with Murraya at dose of 600 mg/kg when compared with control.In the ibuprofen group, the mean reaction time at 0 hr was 0.28±0.04, at 1 hr 0.34±0.05, at 2 hrs 0.46±0.03, at 3 hrs 0.61±0.05, at 4 hrs 0.76±0.05. The mean reaction time Murraya in group 600 mg/kg at 0 hr 0.27±0.04, at 1 hrs 0.39±0.03, at 2 hrs 0.48±0.06, at 3 hrs 0.68±0.05, at 6 hrs 0.80±0.03, respectively.Conclusions: The results indicate that the aqueous extract of Murraya (leaf) extract revealed significant analgesic and anti-inflammatory in thermal and chemical induced pain models

Renormalization group study of the Kondo problem at a junction of several Luttinger wires

We study a system consisting of a junction of N quantum wires, where the junction is characterized by a scalar S-matrix, and an impurity spin is coupled to the electrons close to the junction. The wires are modeled as weakly interacting Tomonaga-Luttinger liquids. We derive the renormalization group equations for the Kondo couplings of the spin to the electronic modes on different wires, and analyze the renormalization group flows and fixed points for different values of the initial Kondo couplings and of the junction S-matrix (such as the decoupled S-matrix and the Griffiths S-matrix). We generally find that the Kondo couplings flow towards large and antiferromagnetic values in one of two possible ways. For the Griffiths S-matrix, we study one of the strong coupling flows by a perturbative expansion in the inverse of the Kondo coupling; we find that at large distances, the system approaches the ferromagnetic fixed point of the decoupled S-matrix. For the decoupled S-matrix with antiferromagnetic Kondo couplings and weak inter-electron interactions, the flows are to one of two strong coupling fixed points in which all the channels are strongly coupled to each other through the impurity spin. But strong inter-electron interactions, with K_\rho < N/(N+2), stabilize a multi-channel fixed point in which the coupling between different channels goes to zero. We have also studied the temperature dependence of the conductance at the decoupled and Griffiths S-matrices.Comment: Revtex4, 16 pages including 6 figure

Phytochemical and Anti-Inflammatory Evaluation of Herbal Gel Prepared from Bark Extract of Mesua Ferrea Linn

The present research work involves formulation of herbal gel containing stem bark extracts of Mesua ferrea Linn and its evaluation for in vitro anti-inflammatory activity. The gel formulations were prepared using ethanolic extracts along with different polymer. The physiochemical parameters of formulations like; pH, viscosity and spreadability etc. also evaluated. Phytochemical analysis revealed presence of phenols, flavonoids and alkaloids, etc. The ethanolic extracts showed appreciable anti-inflammatory activity compared to the standard drug. Study confirmed that potential anti-inflammatory formulation can be developed from bark extract of Mesua ferrea Linn.&nbsp;&nbsp; Keywords: Mesua ferrea Linn., Anti-inflammatory, Herbal Gel, Phytochemical, Albumin denaturation

Immunohistochemical Expression of Anaplastic Lymphoma Kinase in Invasive Breast Carcinomas- A Retrospective Study

Introduction: Breast carcinoma remains one of the most common causes of mortality among female cancer patients inspite of improvements in treatment modalities. Increased survival rate can be achieved by identification of new targeted therapies. Anaplastic Lymphoma Kinase (ALK) alterations are present in many solid and haematological tumours indicating its role in pathogenesis and treatment. There are studies regarding the expression of ALK in few breast cancers but its importance was not clearly mentioned. Hence, identification of ALK overexpression in breast cancers, particularly in Triple Negative Breast Cancers (TNBC) might play a role in their chemotherapy with the help of ALK inhibitors. Aim: To study the ALK expression in different subtypes of invasive carcinomas of breast. Materials and Methods: This was a retrospective cross-sectional study conducted in the Department of Pathology at Great Eastern Medical School (GEMS) and Hospital, Srikakulam, Andhra Pradesh, India, from January 2022 to July 2022. The data of 60 patients, from January 2021 to December 2021 was retrieved using Hospital Information Management System (HIMS) and the Haematoxylin and Eosin (H&E)-stained slides and formalin fixed paraffin embedded tissue blocks of breast tumour were retrieved and reviewed. Estrogen receptor (ER), Progesterone receptor (PR) and Human Epidermal growth factor Receptor 2 (HER2) immunostains were performed and categorised based on molecular classification as Luminal, Her2 and Triple negative. ALK Staining was performed on all cases and its expression was studied. Statistical Package for Social Sciences (SPSS) software version 2.0 was used for analysis of data. Mean with standard deviation is used for quantitative variables and prevalence, ratio is used for quantitative variables. Chi-square test and Fischer exact test were used for detecting significance. The p-value <0.05 was considered as significant. Results: Out of 60 cases, majority (N=22; 36.66%) of patients were in the age group of 51-60 years. The mean tumour size was 3.2±0.5 cm. The most common histological type was invasive breast carcinoma, No Special Type (N=44; 73.34%). Majority of the tumours showed grade 1 and 2 with 24 (40%) and 25 (41.67%) cases, respectively. A total of 30 cases (50%) of tumours belonged to stage T2. Luminal molecular subtype was the most common 31 (51.67%) cases followed by TNBC, 16 (26.67%) cases and Her2neu 13 (21.67%) cases. Among all the cases, ALK overexpression was seen in 17 (28.33%) cases and among different molecular subtypes, its expression was seen in 5 (8.33%) cases of Luminal type, 3 (5.0%) cases of HER2 type and in 9 (15.0%) cases of TNBC cases. Conclusion: Immunohistochemical analysis showed ALK over expression in a substantial proportion of cases and possibly plays a significant role in aggressive behaviour of breast cancer. ALK inhibitors offer an opportunity to treat aggressive subtypes of breast cancer

Preclinical formulation for the pharmacokinetics and efficacy of GBO-006, a selective polo like kinase 2 (PLK2) inhibitor for the treatment of triple negative breast cancer

GBO-006 was shown to be a highly specific and selective PLK2 inhibitor that promoted mitotic arrest in various cancer cell lines, subsequently resulting in their apoptotic death. Intraperitoneal alternate day dosing of GBO-006 using 100 % DMSO as formulation showed significant tumor regression in xenograft models, demonstrating proof of concept of PLK2 inhibition in vivo. These studies necessitated the development of a suitable and GRAS (generally considered as safe) preformulation for pharmacokinetic and efficacy studies. GBO-006 possesses challenging physicochemical and biopharmaceutical properties like poor solubility in aqueous media, low permeability and a crystalline nature. Different methods like cosolvency, complexation and micellar solubilization were employed to improve the solubility of GBO-006. A strategy of co-solvency is used to solubilize the GBO-006 up to 10 mg/mL. A formulation with 20 % DMSO, 40 % PEG 400, 30 % of 100 mM citrate buffer (pH 3.0) and 10 % solutol displayed clear solution without any visual precipitation of the drug even after 2 weeks of storage. GBO-006 showed moderate clearance in rat and high systemic clearance in mouse and dog. It showed poor oral bioavailability across all species. Intraperitoneal dosing of GBO-006 demonstrated the linear exposure. GBO-006 showed significant inhibition of tumor progression

A candidate relativistic tidal disruption event at 340 Mpc

We present observations of an extreme radio flare, VT J024345.70-284040.08, hereafter VT J0243, from the nucleus of a galaxy with evidence for historic Seyfert activity at redshift $z=0.074$. Between NRAO VLA Sky Survey observations in 1993 to VLA Sky Survey observations in 2018, VT J0243 rose from a ${\sim}$GHz radio luminosity of $\nu L_\nu \lesssim 10^{38}$ erg s$^{-1}$ to $\nu L_\nu{\sim}10^{40}$ erg s$^{-1}$, and still continues to brighten. The radio spectral energy distribution (SED) evolution is consistent with a nascent jet that has slowed over ${\sim}3000$ days with an average $0.1 < \langle \beta \rangle < 0.6$. The jet is energetic (${\sim}10^{51-52}$ erg), and had a radius ${\sim}0.7$ pc in Dec. 2021. X-ray observations suggest a persistent or evolving corona, possibly associated with an accretion disk, and IR and optical observations constrain any high-energy counterpart to be sub-Eddington. VT J0243 may be an example of a young, off-axis radio jet from a slowly evolving tidal disruption event. Other more mysterious triggers for the accretion enhancement and jet launching are possible. In either case, VT J0243 is a unique example of a nascent jet, highlighting the unknown connection between supermassive black holes, the properties of their accretion flows, and jet launching.Comment: 20 pages, 5 figures, 3 tables. Submitted to Ap