Thermomechanically-controlled Processing for Producing Ship-building Steels

The thermomechanically-controlled processing of a newly developed high-strength lowalloy steel has been designed in such a way that the problems, normally faced in producing thequench and tempered steels, have been mitigated and the final product (steel plates) are available in as rolled condition rather than quench and tempered steels.A low-carbon, low-alloy steel having nickel, chromium, copper, niobium, boron, has been designed for ease of welding, improved weldability over the conventional steels, and responsiveto the thermomechanically-controlled processing. A number of laboratory-scale batches of the alloy were made with different combinations of thermomechanically-controlled processingparameters. The different thermomechanically-controlled processing parameters studied include (i) slab-reheating temperature,~ (ii). def.orm ation above recrvstallisation temperature, (iii)deformation below recrystallisation temperature, and (iv) finish-rolling temperature. The thermomechanically-processed steel plates, under certain combinations of  thermomechanically-controlled ~rocessi-ne.o arameters. showed excellent combination of imvact and tensile n.r on. erties. In this paper, the microstructure-property correlation has been made to throw light on the type of microstructure required to obtain such superior package of mechanical properties. Further, the optimised laboratory-scale thermomechanically-controlled processing parameters, which were used to process newer hatches of the steel made through industrial route, have delivered encouraging results

Description of Two New Species of Phleobum Haldar and Chakraborty, 1974 along with a Major Taxonomic Revision of the Genus

Two new species of Phleobum (Apicomplexa: Eugregarinida: Hirmocystidae) are described from adult grasshoppers in Kalyani, India. Phleobum globuloepimeritum n. sp. is described from Oxya hyla hyla (Insecta: Orthoptera: Acrididae) and Phleobum elliptica n. sp. from Atractomorpha crenulata (Insecta: Orthoptera: Pyrgomorphidae). In P. globuloepimeritum, the trophozoites are solitary, orangecoloured, have a maximum length of 352 μm with a hyaline globular epimerite and the protomerite in satellite is characteristically flanged. The gametocyst is orange, orbicular, averaging 300 × 250 μm in size, dehiscing through a pore after 50 h. The oocysts are uniformly smooth, ellipsoidal, measuring 9 × 5 μm. In P. elliptica trophozoites are also solitary, orange-coloured, having a maximum length of 157 μm with triangular epimerites. The protomerite flange is typically a bowel-shaped collar. The gametocyst is yellow-orange, ellipsoidal, averaging 240 × 165 μm and dehisces through a pore after 72 h, releasing smooth-walled, ellipsoidal, uniformly shaped oocysts measuring 5 × 3 μm. The two new species share traits, which define the genus such as: gamonts in association, satellites with characteristic flange and gametocysts dehiscence through a single pore. The epimerite of P. globuloepimeritum is hyaline and globular, which is unique among members of the genus. The gametocyst of P. elliptica is notably ellipsoidal. Basing on observation on all the described and present two species, generic characters of the genus Phleobum have been redefined. The genus is also transferred from the family Didymophyidae to the family Hirmocystidae as the gametocysts in all the species of Phleobum dehisce through a pore

Two New Species of Myxobolus Bütschli, 1882 (Myxozoa: Myxosporea: Bivalvulida) from Food Fishes of West Bengal, India – a Light and Scanning Electron Microscopy Study

Two new myxozoan species – Myxobolus analfinus sp. n. and Myxobolus debsantus sp. n. are described from Heteropneustes fossilis (Bloch) and Catla-Rohu hybrid carp [Male parent fish Catla catla (Hamilton Buchanan) × Female parent fish Labeo rohita (Hamilton- Buchanan)], respectively. Spores of Myxobolus analfinus are oval with slightly acuminate anterior end and large prominent intercapsular notch. On the other hand, in Myxobolus debsantus spores are spherical to oval with intercapsular notch and posterior sutural markings. In both the myxobolid species polar capsules are unequal. The detailed light microscopic and SEM structures and measurements of these two myxozoans are given

Impaired skin wound healing in peroxisome proliferator–activated receptor (PPAR)α and PPARβ mutant mice

We show here that the α, β, and γ isotypes of peroxisome proliferator–activated receptor (PPAR) are expressed in the mouse epidermis during fetal development and that they disappear progressively from the interfollicular epithelium after birth. Interestingly, PPARα and β expression is reactivated in the adult epidermis after various stimuli, resulting in keratinocyte proliferation and differentiation such as tetradecanoylphorbol acetate topical application, hair plucking, or skin wound healing. Using PPARα, β, and γ mutant mice, we demonstrate that PPARα and β are important for the rapid epithelialization of a skin wound and that each of them plays a specific role in this process. PPARα is mainly involved in the early inflammation phase of the healing, whereas PPARβ is implicated in the control of keratinocyte proliferation. In addition and very interestingly, PPARβ mutant primary keratinocytes show impaired adhesion and migration properties. Thus, the findings presented here reveal unpredicted roles for PPARα and β in adult mouse epidermal repair

Skeletal muscle metastases in neuroblastoma share common progenitors with primary tumor and biologically resemble stage MS disease

IntroductionWhile subcutaneous metastases are often observed with stage MS neuroblastoma, an entity that usually resolves spontaneously, skeletal muscle metastases (SMM) have been rarely described. The purpose of this retrospective study was to investigate the significance of SMM in neuroblastoma.Patients and methodsSeventeen patients with neuroblastoma SMM were diagnosed at a median age of 4.3 (0.1-15.6) months. All had SMM at diagnosis and metastases at other sites. Fifteen (88%) had ≥ 2 SMM in disparate muscle groups. One, 14, and 2 patients had low, intermediate, and high-risk disease respectively. Fifteen tumors had favorable histology without MYCN amplification, and 2 were MYCN-amplified. Most SMM (80%; n=12/15 evaluated) were MIBG-avid.ResultsOnly 1 patient (with MYCN-non-amplified neuroblastoma) had disease progression. All survive at median follow-up of 47.9 (16.9-318.9) months post-diagnosis. Biological markers (histology, chromosomal and genetic aberrations) were not prognostic. Whole genome sequencing of 3 matched primary and SMM lesions suggested that both primary and metastatic tumors arose from the same progenitor. SMM completely resolved in 10 patients by 12 months post-diagnosis. Of 4 patients managed with watchful observation alone without any cytotoxic therapy, 3 maintain complete remission with SMM resolving by 5, 13, and 21 months post-diagnosis respectively.ConclusionsChildren with neuroblastoma SMM have an excellent prognosis, with a clinical course suggestive of stage MS disease. Based on these results, the initial management of infants with non-MYCN-amplified NB with SMM could be watchful observation, which could eliminate or reduce exposure to genotoxic therapy

Photodynamic Treatment Induces an Apoptotic Pathway Involving Calcium, Nitric Oxide, p53, p21-Activated Kinase 2, and c-Jun N-Terminal Kinase and Inactivates Survival Signal in Human Umbilical Vein Endothelial Cells

Photodynamic treatment (PDT) elicits a diverse range of cellular responses, including apoptosis. Previously, we showed that PDT stimulates caspase-3 activity, and subsequent cleavage and activation of p21-activated kinase 2 (PAK2) in human epidermal carcinoma A431 cells. In the current study, pretreatment with nitric oxide (NO) scavengers inhibited PDT-induced mitochondrial membrane potential (MMP) changes, activation of caspase-9, caspase-3, p21-activated protein kinase 2 (PAK2) and c-Jun N-terminal kinase (JNK), and gene expression of p53 and p21 involved in apoptotic signaling. Moreover, PAK2 activity was required for PDT-induced JNK activation and apoptosis. Inhibition of p53 mRNA expression using small interfering RNA (siRNA) additionally blocked activation of PAK2 and apoptosis induced by PDT. Importantly, our data also show that PDT triggers cell death via inactivation of ERK-mediated anti-apoptotic pathway. PDT triggers cell death via inactivation of the HSP90/multi-chaperone complex and subsequent degradation of Ras, further inhibiting anti-apoptotic processes, such as the Ras→ERK signal transduction pathway. Furthermore, we did not observe two-stage JNK activation for regulation of PAK2 activity in the PDT-induced apoptotic pathway in HUVECs, which was reported earlier in A431 cells. Based on the collective results, we have proposed a model for the PDT-triggered inactivation of the survival signal and apoptotic signaling cascade with Rose Bengal (RB), which sequentially involves singlet oxygen, Ca2+, NO, p53, caspase-9, caspase-3, PAK2, and JNK

Understanding the Role of PknJ in Mycobacterium tuberculosis: Biochemical Characterization and Identification of Novel Substrate Pyruvate Kinase A

Reversible protein phosphorylation is a prevalent signaling mechanism which modulates cellular metabolism in response to changing environmental conditions. In this study, we focus on previously uncharacterized Mycobacterium tuberculosis Ser/Thr protein kinase (STPK) PknJ, a putative transmembrane protein. PknJ is shown to possess autophosphorylation activity and is also found to be capable of carrying out phosphorylation on the artificial substrate myelin basic protein (MyBP). Previous studies have shown that the autophosphorylation activity of M. tuberculosis STPKs is dependent on the conserved residues in the activation loop. However, our results show that apart from the conventional conserved residues, additional residues in the activation loop may also play a crucial role in kinase activation. Further characterization of PknJ reveals that the kinase utilizes unusual ions (Ni2+, Co2+) as cofactors, thus hinting at a novel mechanism for PknJ activation. Additionally, as shown for other STPKs, we observe that PknJ possesses the capability to dimerize. In order to elucidate the signal transduction cascade emanating from PknJ, the M. tuberculosis membrane-associated protein fraction is treated with the active kinase and glycolytic enzyme Pyruvate kinase A (mtPykA) is identified as one of the potential substrates of PknJ. The phospholabel is found to be localized on serine and threonine residue(s), with Ser37 identified as one of the sites of phosphorylation. Since Pyk is known to catalyze the last step of glycolysis, our study shows that the fundamental pathways such as glycolysis can also be governed by STPK-mediated signaling

Terminal Deoxynucleotidyl Transferase: The Story of A Misguided DNA Polymerase

Nearly every DNA polymerase characterized to date exclusively catalyzes the incorporation of mononucleotides into a growing primer using a DNA or RNA template as a guide to direct each incorporation event. There is, however, one unique DNA polymerase designated terminal deoxynucleotidyl transferase that performs DNA synthesis using only single-stranded DNA as the nucleic acid substrate. In this chapter, we review the biological role of this enigmatic DNA polymerase and the biochemical mechanism for its ability to perform DNA synthesis in the absence of a templating strand. We compare and contrast the molecular events for template-independent DNA synthesis catalyzed by terminal deoxynucleotidyl transferase with other well-characterized DNA polymerases that perform template-dependent synthesis. This includes a quantitative inspection of how terminal deoxynucleotidyl transferase binds DNA and dNTP substrates, the possible involvement of a conformational change that precedes phosphoryl transfer, and kinetic steps that are associated with the release of products. These enzymatic steps are discussed within the context of the available structures of terminal deoxynucleotidyl transferase in the presence of DNA or nucleotide substrate. In addition, we discuss the ability of proteins involved in replication and recombination to regulate the activity of the terminal deoxynucleotidyl transferase. Finally, the biomedical role of this specialized DNA polymerase is discussed focusing on its involvement in cancer development and its use in biomedical applications such as labeling DNA for detecting apoptosis

Measurement of anti-3He nuclei absorption in matter and impact on their propagation in the Galaxy

In our Galaxy, light antinuclei composed of antiprotons and antineutrons can be produced through high-energy cosmic-ray collisions with the interstellar medium or could also originate from the annihilation of dark-matter particles that have not yet been discovered. On Earth, the only way to produce and study antinuclei with high precision is to create them at high-energy particle accelerators. Although the properties of elementary antiparticles have been studied in detail, the knowledge of the interaction of light antinuclei with matter is limited. We determine the disappearance probability of anti-3He when it encounters matter particles and annihilates or disintegrates within the ALICE detector at the Large Hadron Collider. We extract the inelastic interaction cross section, which is then used as an input to the calculations of the transparency of our Galaxy to the propagation of anti-3He stemming from dark-matter annihilation and cosmic-ray interactions within the interstellar medium. For a specific dark-matter profile, we estimate a transparency of about 50%, whereas it varies with increasing anti-3He momentum from 25% to 90% for cosmic-ray sources. The results indicate that anti-3He nuclei can travel long distances in the Galaxy, and can be used to study cosmic-ray interactions and dark-matter annihilation