SOUTH CHINA SEA: THE CHINESE APPROACH

The international community has shown considerable interest in China's assertiveness in the South China Sea in recent times. The objective of this study is to examine the strengths and weaknesses that form the foundation of Chinese strategies, and decipher the underlying motives and strategies employed by China in its pursuits. The paper evaluates China's current position in the South China Sea and its effects on regional stability and global geopolitics. The findings reveal that China follows a holistic approach with significant infrastructure, diplomatic, and regional geopolitical gains. These efforts expose risks such as regional alliance tensions, international legal framework complexity and though rare but potential armed engagements.   Bibliography Entry Hussain Awan SI (M), Sajjad. 2023. "South China Sea: The Chinese Approach." Margalla Papers 27 (2): 44-59

SOUTH CHINA SEA: THE CHINESE APPROACH

The international community has shown considerable interest in China's assertiveness in the South China Sea in recent times. The objective of this study is to examine the strengths and weaknesses that form the foundation of Chinese strategies, and decipher the underlying motives and strategies employed by China in its pursuits. The paper evaluates China's current position in the South China Sea and its effects on regional stability and global geopolitics. The findings reveal that China follows a holistic approach with significant infrastructure, diplomatic, and regional geopolitical gains. These efforts expose risks such as regional alliance tensions, international legal framework complexity and though rare but potential armed engagements.   Bibliography Entry Hussain Awan SI (M), Sajjad. 2023. "South China Sea: The Chinese Approach." Margalla Papers 27 (2): 44-59

Thermal Model of Rotary Friction Welding for Similar and Dissimilar Metals

Friction welding is one of the foremost welding processes for similar and dissimilar metals. Previously, the process has been modeled utilizing the rudimentary techniques of constant friction and slip-stick friction. The motivation behind this article is to present a new characteristic for temperature profile estimation in modeling of the rotary friction welding process. For the first time, a unified model has been exhibited, with an implementation of the phase transformation of similar and dissimilar materials. The model was generated on COMSOL Multiphysics® and thermal and structural modules were used to plot the temperature curve. The curve for the welding of dissimilar metals using the model was generated, compared and analyzed with that of practical curves already acquired through experimentation available in the literature, and then the effect of varying the parameters on the welding of similar metals was also studied

Observation of Temperature-Induced Crossover to an Orbital-Selective Mott Phase in Ax_{x}Fe2−y_{2-y}Se2_2 (A=K, Rb) Superconductors

In this work, we study the A$_{x}$Fe$_{2-y}$Se$_2$ (A=K, Rb) superconductors using angle-resolved photoemission spectroscopy. In the low temperature state, we observe an orbital-dependent renormalization for the bands near the Fermi level in which the dxy bands are heavily renormliazed compared to the dxz/dyz bands. Upon increasing temperature to above 150K, the system evolves into a state in which the dxy bands have diminished spectral weight while the dxz/dyz bands remain metallic. Combined with theoretical calculations, our observations can be consistently understood as a temperature induced crossover from a metallic state at low temperature to an orbital-selective Mott phase (OSMP) at high temperatures. Furthermore, the fact that the superconducting state of A$_{x}$Fe$_{2-y}$Se$_2$ is near the boundary of such an OSMP constraints the system to have sufficiently strong on-site Coulomb interactions and Hund's coupling, and hence highlight the non-trivial role of electron correlation in this family of iron superconductors

Spectral Evidence for Emergent Order in Ba1−x_{1-x}Nax_xFe2_2As2_2

We report an angle-resolved photoemission spectroscopy study of the iron-based superconductor family, Ba$_{1-x}$Na$_x$Fe$_2$As$_2$. This system harbors the recently discovered double-Q magnetic order appearing in a reentrant C$_4$ phase deep within the underdoped regime of the phase diagram that is otherwise dominated by the coupled nematic phase and collinear antiferromagnetic order. From a detailed temperature-dependence study, we identify the electronic response to the nematic phase in an orbital-dependent band shift that strictly follows the rotational symmetry of the lattice and disappears when the system restores C$_4$ symmetry in the low temperature phase. In addition, we report the observation of a distinct electronic reconstruction that cannot be explained by the known electronic orders in the system

Master of mimicry: Rare primary cutaneous anaplastic large cell lymphoma presenting as fungating parotid tumor–case report and review

Introduction Primary cutaneous anaplastic large cell lymphomas (PC-ALCL) are rare. They fall within non-Hodgkin's lymphomas spectrum. Commonly misdiagnosed, this malignancy involving the skin has favorable prognosis. To the best of our knowledge, this is the first reported case of PC-ALCL involving the parotid gland. This clinical presentation can mislead surgeons. We highlight this diagnostic conundrum. Case presentation A 73-year-old gentleman presented with two painless, ulcerating nodules over the right pre-auricular and angle of the mandible. Prior to that, he had right pre-auricular swelling that enlarged over a year. Skin nodules erupted few weeks before seeking treatment. Computed Tomography scan reported homogenously enhancing masses at posterior part of parotid gland's superficial lobe with diffuse lobe enlargement and no regional lymphadenopathy. A hypodense lesion at the liver indicated metastasis. Biopsy revealed PC-ALCL. He responded well to chemotherapy. Discussion PC-ALCL commonly presents as solitary nodules that can ulcerate over the head and neck region. Reports of PC-ALCL involving the eyelids, lips, and breast were found in our literature review. Multifocal lesions occur in 20% of cases. Malignant parotid tumors are aggressive and require parotidectomy which carry the risk of facial nerve injury. Treatment of PC-ALCL however, is local excision and radiotherapy for solitary lesions; and chemotherapy for those with extracutaneous spread. The 5-year survival rate is 90% in PC-ALCL. Conclusion PC-ALCL is a master of mimicry. To prevent serious morbidity, awareness regarding this entity as a differential diagnosis compared to the common malignant parotid tumors need to be raised

Tandem quadruplication of HMA4 in the zinc (Zn) and cadmium (Cd) hyperaccumulator noccaea caerulescens

Zinc (Zn) and cadmium (Cd) hyperaccumulation may have evolved twice in the Brassicaceae, in Arabidopsis halleri and in the Noccaea genus. Tandem gene duplication and deregulated expression of the Zn transporter, HMA4, has previously been linked to Zn/Cd hyperaccumulation in A. halleri. Here, we tested the hypothesis that tandem duplication and deregulation of HMA4 expression also occurs in Noccaea. A Noccaea caerulescens genomic library was generated, containing 36,864 fosmid pCC1FOSTM clones with insert sizes ~20–40 kbp, and screened with a PCR-generated HMA4 genomic probe. Gene copy number within the genome was estimated through DNA fingerprinting and pooled fosmid pyrosequencing. Gene copy numbers within individual clones was determined by PCR analyses with novel locus specific primers. Entire fosmids were then sequenced individually and reads equivalent to 20-fold coverage were assembled to generate complete whole contigs. Four tandem HMA4 repeats were identified in a contiguous sequence of 101,480 bp based on sequence overlap identities. These were flanked by regions syntenous with up and downstream regions of AtHMA4 in Arabidopsis thaliana. Promoter-reporter b-glucuronidase (GUS) fusion analysis of a NcHMA4 in A. thaliana revealed deregulated expression in roots and shoots, analogous to AhHMA4 promoters, but distinct from AtHMA4 expression which localised to the root vascular tissue. This remarkable consistency in tandem duplication and deregulated expression of metal transport genes between N. caerulescens and A. halleri, which last shared a common ancestor >40 mya, provides intriguing evidence that parallel evolutionary pathways may underlie Zn/Cd hyperaccumulation in Brassicaceae