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Self-organized criticality emerges in dynamical complex systems driven out of equilibrium and characterizes a wide range of classical phenomena in physics, geology, and biology. We report on a quantum coherence-controlled self-organized critical transition observed in the light localization behavior of a coherence-driven nanophotonic configuration. Our system is composed of a gain-enhanced plasmonic heterostructure controlled by a coherent drive, in which photons close to the stopped-light regime interact in the presence of the active nonlinearities, eventually synchronizing their dynamics. In this system, on the basis of analytical and corroborating full-wave Maxwell-Bloch computations, we observe quantum coherence-controlled self-organized criticality in the emergence of light localization arising from the synchronization of the photons. It is associated with two first-order phase transitions: one pertaining to the synchronization of the dynamics of the photons and the second pertaining to an inversionless lasing transition by the coherent drive. The so-attained light localization, which is robust to dissipation, fluctuations, and many-body interactions, exhibits scale-invariant power laws and absence of finely tuned control parameters. We also found that, in this nonequilibrium dynamical system, the effective critical "temperature" of the system drops to zero, whereupon one enters the quantum self-organized critical regime.

A circularly polarized compact two-port MIMO antenna is presented along with asymmetrical CPW feed and a novel decoupling structure. The asymmetric CPW feed of the antenna is improving the impedance matching significantly and shifting the operating band towards the lower frequency. The novel inverted Z-shaped decoupling is used to enhance the isolation which mitigates the surface wave effectively between two antennas. The triangular-shaped inductive stubs are unified in the inverted Z-shaped decoupling structure which is used to perturb the surface wave movement and to influence the circular polarization (CP) behaviour in the two-port antenna. MIMO antenna obtains the 10 dB impedance bandwidth (IBW) from 6.38 GHz to 6.84 GHz along with minimum port isolation of 30 dB. The 3-dB axial ratio (AR) is obtained from 6.59 to 6.84 GHz frequency which is 52.1% of the total 10 dB IBW of the antenna. The proposed work can be prominent for super-extended C-band of satellite communication and Wi-Fi 6E U-NII6 and U-NII7 communication. [ABSTRACT FROM AUTHOR]

The establishment of regional groupings has become increasingly common, especially amongst developing countries. The formation of the South Asian Association for Regional Cooperation (SAARC) in 1985 ushered in the era of institutionalized regionalism in South Asia. However, as a regional institution the SAARC has yet to fully achieve its objectives after three decades of its establishment. This raises the question: why has regionalism in the South Asian region under the SAARC framework failed to deliver substantial achievements? A secondary question arises: how can the SAARC cope with the changing dynamics of the region? In this paper, we will address both questions relying on interviews with informed individuals as well as documentary evidence from primary and secondary sources. Keywords: India, Pakistan, Bangladesh, Nepal, Sri Lanka, Maldives, Bhutan, Afghanistan, Regionalism, SAARC, South Asia, Regional Cooperation, Regional Integration, Supranationalism, The world has witnessed a proliferation of regional institutions in the past few decades. Regional arrangements have not only managed to enhance social, political and economic interaction amongst countries but [...]

Metasurfaces are optically thin layers of subwavelength resonators that locally tailor the electromagnetic response at the nanoscale. Our metasurface research aims at developing novel designs and applications of metasurfaces that go beyond the classical regimes. In contrast to conventional phase gradient metasurfaces where each meta-atom responds individually, we are interested in developing metasurfaces where neighboring meta-atoms are strongly coupled. By engineering a non-Hermitian coupling between the meta-atoms, new degrees of freedom are introduced and novel functionalities can be achieved. We are also interested in combining classical metasurface with quantum emitters, which may offer opportunities for on-chip quantum technologies. Additionally, we have been designing metasurfaces to realize exciting phenomena and applications, such as ultrathin metasurface cloak and strong photonic spin-Hall effect. In this paper, we review our research efforts in optical metasurfaces in the past few years, which ranges from conventional to novel type of metasurface and from classical to quantum regime.

Purpose: Leg muscle microvascular blood flow (perfusion) is impaired in response to maximal exercise in patients with peripheral artery disease (PAD); however, during submaximal exercise, microvascular perfusion is maintained due to a greater increase in microvascular blood volume compared with that seen in healthy adults. It is unclear whether this submaximal exercise response reflects a microvascular impairment, or whether it is a compensatory response for the limited conduit artery flow in PAD. Therefore, to clarify the role of conduit artery blood flow, we compared whole-limb blood flow and skeletal muscle microvascular perfusion responses with exercise in patients with PAD (n=9; 60±7 years) prior to, and following, lower-limb endovascular revascularization. Materials and Methods: Microvascular perfusion (microvascular volume × flow velocity) of the medial gastrocnemius muscle was measured before and immediately after a 5 minute bout of submaximal intermittent isometric plantar-flexion exercise using contrast-enhanced ultrasound imaging. Exercise contraction-by-contraction whole-leg blood flow and vascular conductance were measured using strain-gauge plethysmography. Results: With revascularization there was a significant increase in whole-leg blood flow and conductance during exercise (p<0.05). Exercise-induced muscle microvascular perfusion response did not change with revascularization (pre-revascularization: 3.19±2.32; post-revascularization: 3.89±1.67 aU.s−1; p=0.38). However, the parameters that determine microvascular perfusion changed, with a reduction in the microvascular volume response to exercise (pre-revascularization: 6.76±3.56; post-revascularization: 2.42±0.69 aU; p<0.01) and an increase in microvascular flow velocity (pre-revascularization: 0.25±0.13; post-revascularization: 0.59±0.25 s−1; p=0.02). Conclusion: These findings suggest that patients with PAD compensate for the conduit artery blood flow impairment with an increase in microvascular blood volume to maintain muscle perfusion during submaximal exercise. Clinical Impact: The findings from this study support the notion that the impairment in conduit artery blood flow in patients with PAD leads to compensatory changes in microvascular blood volume and flow velocity to maintain muscle microvascular perfusion during submaximal leg exercise. Moreover, this study demonstrates that these microvascular changes are reversed and become normalized with successful lower-limb endovascular revascularization. [ABSTRACT FROM AUTHOR]

The Mesoscale to Microscale Coupling team, part of the U.S. Department of Energy Atmosphere to Electrons (A2e) initiative, has studied various important challenges related to coupling mesoscale models to microscale models for the use case of wind energy development and operation. Several coupling methods and techniques for generating turbulence at the microscale that is subgrid to the mesoscale have been evaluated for a variety of cases. Case studies included flat-terrain, complex-terrain, and offshore environments. Methods were developed to bridge the terra incognita, which scales from about 100m through the depth of the boundary layer. The team used wind-relevant metrics and archived code, case information, and assessment tools and is making those widely available. Lessons learned and discerned best practices are described in the context of the cases studied for the purpose of enabling further deployment of wind energy. [ABSTRACT FROM AUTHOR]

Quantum photonic technologies such as quantum sensing, metrology, and simulation could be transformatively enabled by the availability of integrated single photon sources with high radiative rates and photon collection efficiencies. We address these challenges for quantum emitters formed from color center defect sites such as those in hexagonal boron nitride, which are promising candidates as single photon sources due to their bright, stable, polarized, and room temperature emission. We report design of a nanophotonic coupler from color center quantum emitters to a dielectric metasurface lens. The coupler is comprised of a hybrid plasmonic–dielectric resonator that achieves a large radiative Purcell enhancement and partial control of far-field radiation. We report radiative Purcell factors up to 285 and photon collection efficiencies up to 89% for a lossless metasurface, applying a continuous hyperboloidal phase-front. Our hybrid plasmonic–dielectric coupler interfacing two nanophotonic elements is a compound optical element, analogous to those found in microscope objective lenses, which combine multiple optical functions into a single component for improved performance. [ABSTRACT FROM AUTHOR]

This paper examines the notion of region as they figure in certain literary texts of the medieval and early modern north India across diverse linguistic archives. The idea is to look at and beyond how these compositions understood and represented the region. What were the constituent factors of the region, and how do they manifest themselves? As an imagined, lived, constituted and contested idea, what are the varying set of traits associated with regions? Is it possible to make a repertoire of such traits outside of contemporary and temporally-spatially specific discourses available within particular literary cultures? No less important is the question of how modern historians might fruitfully relate to, and deploy, the fraught category while researching any aspect of pre-modern past, and not just while dealing with local/regional/vernacular. The paper argues that the question of what constitutes region and what constitutes a grander totality, of which a region is but a part, is a matter of contesting claims to power that are settled as much in the domain of cultural representations and resources as in actual political might. [ABSTRACT FROM AUTHOR]

A compact, two-element textile MIMO antenna is designed with enhanced isolation by using modification in the ground, open-ended slots along with shorting pins. Maximum 27.8 dB isolation is achieved in two-element antennae, where the edge-to-edge distance is kept at 0.19 λ 0 which is less than the conventional half wavelength. The Y-shaped decoupling and shorting pins improve the isolation up to 14 dB and can mitigate the current moment between the two ports effectively. The open slots in the ground are enhancing the mutual impedance and shift the operating band of the antenna toward the lower frequency band and thus size miniaturization is also achieved. The textile antenna achieves a 10 dB impedance bandwidth from 4.24 to 5.38 GHz with more than 21.1 dB isolation in the entire band. The phantom wrist model and bending analysis are carried out with the textile antenna to validate the on-body effects of the antenna in wearable and 5G applications. [ABSTRACT FROM AUTHOR]

The article discusses the evolving relationship between India and Association of Southeast Asian Nations (ASEAN), focusing on their strategic partnership and efforts to enhance cooperation in various sectors. Topics include economic ties, defense cooperation, and initiatives to strengthen cultural and educational exchanges, highlighting India's proactive engagement and future prospects for collaboration with ASEAN nations.

This paper presents the design and analysis of a recycling folded-cascode (RFC) OTA intended for any generic capacitive-feedback ECG amplifier. The g m I D methodology is utilized for sizing the RFC OTA, to achieve the prime targets of ultra-low power consumption and low input referred noise. The improved RFC topology is used to achieve higher CMRR. A detailed noise analysis of the overall IA is also included. An account of the chief contributors to the IA's overall noise and design techniques to minimize the same is incorporated. Implemented using UMC 0.18 μ m, the complete circuit consumes a power of 0.47 μ from a 1.8 V supply. The post-layout simulation results show that the designed circuit satisfies all essential specifications of an ECG acquisition system. [ABSTRACT FROM AUTHOR]

The study aimed to determine the pregnancy rates of indigenous field sheep following different approaches to trans-cervical artificial insemination (TCAI). TCAI was performed in oestrus induced ewes using two straws of frozen-thawed semen. In group 1, single-time TCAI was performed on standing heat in traditionally/manually restrained ewes (n=20) and in lab cradle restrained ewes (n=20). In group 2, TCAI was performed in manually restrained ewes single-time after 46-48 h of PGF2a injection (n=20), and double-times at 46-48 h & 52-56 h after PGF2a injection (n=20). In group 3, TCAI was performed in manually restrained ewes single time at 52-56 h after PGF2a injection and 20 minutes after oxytocin injection (n=10), and 20 minutes after oxytocin-estradiol benzoate injection (n=11). The pregnancy rates were 35 % and 45 % in traditional and cradle restrained TCAI, 35 and 55 % in single-time and double-times TCAI, and 50 and 55 % in oxytocin and oxytocin-estradiol cervix-treated TCAI, respectively. Although the pregnancy rates did not differ significantly (p>0.05) by experimental group, the TCAI after cervical treatment and double-time TCAI importantly had more prengnancies than the other approaches to TCAI. Finally, it can be concluded that double-times TCAI would be an effective and acceptable approach for field sheep artificial breeding using frozen semen. [ABSTRACT FROM AUTHOR]