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This paper presents a comprehensive overview of the potential applications for Photo-Acoustic (PA) imaging employing functional nanoparticles. The exploration begins with an introduction to nanotechnology and nanomaterials, highlighting the advancements in these fields and their crucial role in shaping the future. A detailed discussion of the various types of nanomaterials and their functional properties sets the stage for a thorough examination of the fundamentals of the PA effect. This includes a thorough chronological review of advancements, experimental methodologies, and the intricacies of the source and detection of PA signals. The utilization of amplitude and frequency modulation, design of PA cells, pressure sensor-based signal detection, and quantification methods are explored in-depth, along with additional mechanisms induced by PA signals. The paper then delves into the versatile applications of photoacoustic imaging facilitated by functional nanomaterials. It investigates the influence of nanomaterial shape, size variation, and the role of composition, alloys, and hybrid materials in harnessing the potential of PA imaging. The paper culminates with an insightful discussion on the future scope of this field, focusing specifically on the potential applications of photoacoustic (PA) effect in the domain of biomedical imaging and nanomedicine. Finally, by providing the comprehensive overview, the current work provides a valuable resource underscoring the transformative potential of PA imaging technique in biomedical research and clinical practice.

High-quality copper oxide (CuO) thin films were deposited on the silicon (Si) substrate at the room temperature using the physical vapour deposition (PVD) technique named radio frequency (RF) sputtering. The copper-oxide thin-films were single crystalline and of uniform thickness. Subsequently, the influence of growth pressure (low gas pressure - 3 mTorr and high gas pressure - 100 mTorr) and post growth annealing at different temperatures (300 °C to 700 °C) were investigated to understand the microstructural and morphological changes of the thin film. With the influence of growth pressure and post thermal annealing temperature, significant changes in crystallinity, surface roughness, and surface oxidation rate of the CuO thin film were detected, which were adequately analyzed via several characterization techniques. X-ray diffraction (XRD) patterns revealed the phase formation with good crystallinity of the film, which is substantiated by Raman spectroscopy and X-ray photoelectron spectroscopy (XPS) characterization. Atomic force microscopy (AFM) images disclosed that the surface roughness of the film and grain size. By gaining insights into the structural and surface properties of CuO/Si thin films, this research presents new prospects for tuning of CuO phases, structures, and compositions for multifunctional applications.

Abstract We describe the potential utility of Amide Proton Transfer weighted (APTw) Magnetic Resonance Imaging and arterial spin labeling (ASL) in characterizing pilocytic astrocytoma (PA), a type of brain tumor that can be challenging to accurately diagnose and treat. The study included 50 patients with solid or predominantly solid intra-cranial and intra-axial tumors, with 25 patients diagnosed with PA and 25 patients diagnosed with other types of tumors. The study found that the APTw imaging-arterial spin labeling (ASL) mismatch is a new imaging biomarker that could be used to differentiate PA from other types of tumors with a high degree of sensitivity and specificity. The results suggest that APTw imaging and ASL may be useful in characterizing PA, potentially improving diagnosis and treatment planning for this type of brain tumor.

The Southeast Asian (SEA) region has witnessed a relentless surge in energy demand, driven by rapid urbanization, industrialization, and economic growth. In response, the exploration and development of renewable energy sources have gained significant attention. Among these sources, solar energy has emerged as a highly promising candidate due to its remarkable growth rate. This comprehensive review article aims to analyze the challenges and opportunities involved in maximizing solar energy production in the SEA region. The article commences with a succinct introduction to electromagnetic wave spectra and emphasizes the significance of visible spectra. It then provides a comprehensive examination of gross horizontal irradiance (GHI) patterns across the SEA region. A systematic tabulation is presented, organizing the current and potential solar energy installations and outputs of ASEAN countries. The article explores the deployment of hybrid photovoltaic (PV) systems, particularly floating PV installations, as an effective strategy to reduce dependence on fossil fuels. Moreover, the utilization of Supervisory Control and Data Acquisition (SCADA) systems for optimizing solar PV output is investigated. The article further delves into critical maintenance protocols, encompassing corrective, emergency, preventive, and predictive measures, and explores the levelized cost of electricity (LCOE) to assess the profitability of solar PV installations. Lastly, the leadership of Malaysia, Indonesia, and Singapore in solar PV research is highlighted, with a specific focus on building integrated PV and floating PV research. By addressing these, this review article offers valuable insights into the challenges and opportunities for advancing solar energy production in the SEA region.

One major challenge for antiferromagnetic spintronics is how to control the antiferromagnetic state. Here Jani et al. demonstrate the reversible ionic control of the room-temperature magnetic anisotropy and spin reorientation transition in haematite, via the incorporation and removal of hydrogen.

Abstract Cupric oxide (CuO) is a promising candidate as a photocathode for visible‐light‐driven photo‐electrochemical (PEC) water splitting. However, the stability of the CuO photocathode against photo‐corrosion is crucial for developing CuO‐based PEC cells. This study demonstrates a stable and efficient photocathode through the introduction of graphene into CuO film (CuO:G). The CuO:G composite electrodes are prepared using graphene‐incorporated CuO sol–gel solution via spin‐coating techniques. The graphene is modified with two different types of functional groups, such as amine (NH2) and carboxylic acid (COOH). The COOH‐functionalized graphene incorporation into CuO photocathode exhibits better stability and also improves the photocurrent generation compare to control CuO electrode. In addition, COOH‐functionalized graphene reduces the conversion of CuO phase into cuprous oxide (Cu2O) during photo‐electrochemical reaction due to effective charge transfer and leads to a more stable photocathode. The reduction of CuO to Cu2O phase is significantly lesser in CuO:G‐COOH as compared to CuO and CuO:G‐NH2 photocathodes. The photocatalytic degradation of methylene blue (MB) by CuO, CuO:G‐NH2 and CuO:G‐COOH is also investigated. By integrating CuO:G‐COOH photocathode with a sol–gel‐deposited TiO2 protecting layer and Au–Pd nanostructure, stable and efficient photocathode are developed for solar hydrogen generation.

We consider a demand response program in which a block of apartments receive a discount from their electricity supplier if they ensure that their aggregate load from air conditioning does not exceed a predetermined threshold. The goal of the participants is to obtain the discount, while ensuring that their individual temperature preferences are also satisfied. As such, the apartments need to collectively optimise their use of air conditioning so as to satisfy these constraints and minimise their costs. Given an optimal cooling profile that secures the discount, the problem that the apartments face then is to divide the total discounted cost in a fair way. To achieve this, we take a coalitional game approach and propose the use of the Shapley value from cooperative game theory, which is the normative payoff division mechanism that offers a unique set of desirable fairness properties. However, applying the Shapley value in this setting presents a novel computational challenge. This is because its calculation requires, as input, the cost of every subset of apartments, which means solving an exponential number of collective optimisations, each of which is a computationally intensive problem. To address this, we propose solving the optimisation problem of each subset suboptimally, to allow for acceptable solutions that require less computation. We show that, due to the linearity property of the Shapley value, if suboptimal costs are used rather than optimal ones, the division of the discount will be fair in the following sense: each apartment is fairly "rewarded" for its contribution to the optimal cost and, at the same time, is fairly "penalised" for its contribution to the discrepancy between the suboptimal and the optimal costs. Importantly, this is achieved without requiring the optimal solutions.

Pleomorphic xanthoastrocytoma has been considered as an astrocytic tumor with relatively favorable prognosis. It corresponds to WHO Grade-II neoplasm. Recently, several patterns with relatively poor prognosis have been recorded and a new concept of "PXA with anaplastic features" has been proposed. The present case is about a 9-year-old girl who presented with symptoms of recurrent headache, seizures and poor academic performance. MRI revealed left fronto-parietal irregular enhancing mass lesion with callosal involvement and right mid-brain arteriovenous malformation. Clinical and radiological examination was suggestive of a high grade glial neoplasm/PNET. A diagnosis of high grade glial neoplasm was rendered on the squash smears submitted for frozen sections based on the presence of spindle cells, admixed with pleomorphic bizarre, giant cells with multilobated nuclei showing few atypical mitosis and abundant eosinophilic cytoplasm. Frontal craniotomy with debulking of the tumor was performed and permanent sections revealed a biphasic glial neoplasm with spindle cells arranged in fascicles admixed with bizarre multinucleated giant cells showing abundant vacuolated and lipidized cytoplasm, nuclear hyperchromasia with intranuclear inclusions. Eosinophilic granular bodies, mitosis of 7/10 HPF, micro vascular proliferation, necrosis and invasion into the underlying brain parenchyma were noted. With these histomorphological findings a diagnosis of pleomorphic xanthoastrocytoma with anaplastic features was rendered.

Melanotic schwannoma is a rare form of pigmented neural tumor commonly arising from the posterior spinal nerves and ganglia. Two variants have been described, psammomatous and nonpsammomatous. 50% of psammomatous tumors are associated with Carney complex. The biologic behavior of the tumor is difficult to predict and slightly over 10% of the tumors follow malignant course. We present a case of psammomatous melanotic schwannoma as part of Carney complex in a 67-year-old male. Clinical examination revealed oral mucosal and abdominal skin pigmentation. Magnetic resonance imaging showed an intradural extramedullary lesion at D8-D12 level. Intraoperative squash smear study showed sheets of spindle cells with abundant intracytoplasmic melanin pigmentation and few psammoma bodies. Based on clinical, radiologic, and histopathological findings with immunohistochemistry correlation a final diagnosis of psammomatous melanotic schwannoma was rendered.

An integrated strain-based optical modulator driven by a piezoelectric laterally vibrating resonator is demonstrated. The composite structure consists of an acoustic Lamb wave resonator, in which a photonic racetrack resonator is internally embedded to enable overlap of the guided optical mode with the induced strain field. Both types of resonators are defined in an aluminum nitride (AlN) thin film, which rests upon a layer of silicon dioxide in order to simultaneously define optical waveguides, and the structure is released from a silicon substrate. Lateral vibrations produced by the acoustic resonator are transferred through a partially etched layer of AlN, producing a change in the effective index of the guided wave through the interaction of the strain components with the AlN elasto-optic (p) coefficients. Optical modulation through the elasto-optic effect is demonstrated at electromechanically actuated frequencies of 173 MHz and 843 MHz. This device geometry further enables the development of MEMS-based optical modulators in addition to studying elasto-optic interactions in suspended piezoelectric thin films.

Monodisperse maghemite nanoparticles, templated in novel, well-defined pyrazole-containing norbornene-based block copolymers, provided a superparamagnetic nanocomposite with high saturation magnetization at room temperature under an applied magnetic field. The synthesis of the polymer nanocomposites and physical, morphological, and magnetic chracaterization of the nanocomposites are reported. Micelle-encapsulated superparamagnetic nanocomposites were generated for dispersal in aqueous medium. Their stability in water in the presence of a magnetic field was investigated as was their morphology and cell viability, strongly suggesting the potential of these superparamagnetic polymer-based nanocomposites in certain biomedical imaging and associated applications.

Meningiomas are the most common form of primary intracranial tumors, accounting for 13 to 26% of total neoplasms arising from arachnoid cap cells of the meningeal layer covering the central nervous system. Multiple intracranial meningiomas, which often have a syndromic association, account for less than 10% of total meningiomas. Multiple meningiomas with different histological patterns or grades in the same patient are very rare. Here we report such a rare case of meningioma with different histological patterns in the same patient. A 56-year-old lady presented to us with complaints of progressive right-sided weakness and speech disturbances, and her magnetic resonance imaging (MRI) showed two distinct extra-axial lesions over left frontal convexity and left fronto-temporo-parietal convexity. She underwent left fronto-temporo-parietal craniectomy and Simpson grade 1 excision of the lesions. Her histopathological examination revealed two different histological patterns: lesion 1 (left fronto-temporo-parietal convexity) was reported as a transitional World Health Organization (WHO) grade 1 meningioma and lesion 2 (left frontal convexity) was reported as angiomatous WHO grade 1 meningioma. She recovered well and was discharged in a stable condition after 3 weeks. Multiple meningiomas are defined as at least two spatially separated meningiomas occurring at the same time or more than two meningiomas arising sequentially from two clearly distinct regions. The exact mechanism of multicentricity is unknown. The treatment protocol for different histological types in the same patient is not clear. The extent of surgical resection remains the mainstay of the treatment and these patients should be followed up closely to watch for recurrence or malignant transformation. The role of radiotherapy in multiple meningiomas is yet to be established.