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In the present work, an in-house designed special crucible was developed to fabricate isotopically enriched 28Si targets for a γ-ray spectroscopy experiment. Initially, the crucible was tested with natural Si and then utilized to fabricate isotopically enriched 28Si targets of thickness ∼500 μg/cm2 (∼2.15 μm). The fabricated targets were uniform in thickness and had very little contamination. In addition, one of the fabricated targets was successfully utilized in an in-beam γ-ray spectroscopy experiment. The technique employed in the present work not only facilitates the fabrication of stable and pure targets but also minimizes the wastage of the source material. As a result, these efforts pave the way for future fabrication of low-abundance isotopically enriched nuclear physics targets., (© 2024 Author(s). Published under an exclusive license by AIP Publishing.)

Ionic liquids have gained attention as 'designer solvents' since they offer a broad spectrum of properties that can be tuned by altering the constituent ions. In this work, 1-alkyl-2-methyl imidazolium-based ionic liquids with two different alkyl chains (alkyl = hexyl and octyl) have been synthesized and characterized. Since the binary mixture of ionic liquids with molecular solvents can give rise to striking physicochemical properties, the interaction of the synthesized room temperature ionic liquids, 1-hexyl-2-methyl imidazolium bromide [HMIM][Br]/1-octyl-2-methyl imidazolium bromide [OMIM][Br] with DMSO has been examined through density and specific conductance at T = (303.15, 308.15, 313.15 and 318.15) K under atmospheric pressure. The obtained molar volume and excess molar volume are fitted to the Redlich-Kister polynomial equation, and the standard deviation is noted. The positive excess molar volume at elevated temperatures indicates volume expansion due to the mutual loss of dipolar association and differences in the sizes and shapes of the constituent molecules. To have a better understanding of the reactivity and efficacy of 1-hexyl-2-methyl imidazolium bromide and 1-octyl-2-methyl imidazolium bromide with DMSO, the Becke, 3-parameter, Lee-Yang-Parr (B3LYP) correlation function of density functional theory (DFT) has been used. The ORCA Program version 4.0 calculates the highest occupied molecular orbital (HOMO) and lowest unoccupied molecular orbital (LUMO) energy. The effective reactivities of both the compounds that showed an energy band gap (Δ E ), i.e. , the difference between E LUMO and E HOMO , are 7.147 and 8.037 kcal mol -1 ., Competing Interests: The authors have no conflicts of interest to declare., (This journal is © The Royal Society of Chemistry.)

The increasing prevalence of the Internet of Things (IoT) as the primary networking infrastructure in a future society, driven by a strong focus on sustainability and data, is noteworthy. A significant concern associated with the widespread use of Internet of Things (IoT) devices is the insufficient availability of viable strategies for effectively sustaining their power supply and ensuring their uninterrupted functionality. The ability of RF energy-harvesting systems to externally replenish batteries serves as a primary driver for the development of these technologies. To effectively mitigate concerns related to wireless technology, it is imperative to adhere strictly to the mandated limitations on electromagnetic field emissions. A TA broadband polarization-reconfigurable Y-shaped monopole antenna that is improved with a SADEA-tuned smart metasurface is one technique that has been proposed in order to accomplish this goal. A Y-shaped printed monopole antenna is first taken into consideration. To comprehend the process of polarization reconfigurability transitioning from linear to circular polarization (CP), a BAR 50-02 V RF PIN Diode is employed to shorten one of the parasitic conducting strips to the ground plane. A SADEA-driven metasurface, which utilizes the artificial intelligence-driven surrogate model-assisted differential evolution for antenna synthesis, is devised and positioned beneath the radiator to optimize performance trade-offs while increasing the antenna's gain and bandwidth. The ultimate prototype achieves the following: an impedance bandwidth of 2.58 GHz (3.27-5.85 GHz, 48.45%); an axial bandwidth of 1.25 GHz (4.19-5.44 GHz, 25.96%); a peak gain exceeding 8.45 dBic; and when a highly efficient rectifier is integrated, the maximum RF-DC conversion efficiency of 73.82% and DC output of 5.44 V are obtained. Based on the results mentioned earlier, it is considered appropriate to supply power to intelligent sensors and reduce reliance on batteries via RF energy-harvesting mechanisms implemented in hybrid wireless applications.

A miniaturized four-element antenna of 20 mm × 20 mm with edge-to-edge distance of 4.9 mm between the array antennas operating from 4.6−8.6 GHz is investigated in this article. The antenna consists of 4 × integrated dipole driven elements, and complementary split ring resonator (CSRR) metacells are loaded on the both sides of each dipole arms. The loaded meta-couplers magnetically couple to dipole drivers, and the induced resonance effect improves the 10-dB impedance bandwidth (IBW) to 60.6%. To improvise the isolation between antenna elements, metallic vias are implemented that trap electromagnetic (EM)-surface waves to condense into the ground. So, the meta-couplers induce electromagnetic (EM)-propagation as surface wave trapments for radiation and decouple near-field condensed currents, acting as couplers/decouplers. The maximum isolation achieved is >−22.5 dB without any external decoupling network. The diversity parameters indicate good attributes in isotropic, indoor, and outdoor channel environments with an envelope correlation coefficient (ECC) < 0.165 and realized gain of 5.5 dBi with average radiation efficiency of 80−90% in the desired operating bands. An equivalent circuit model using lumped components is designed for the proposed four-element antenna. For validation, a prototype antenna is fabricated and measured to be implemented in 5G applications, which shows good correlation with the full-wave simulated results.

Characteristics and performance of a time of flight (TOF) spectrometer developed for performing fission mass distribution studies are presented. The spectrometer contains two TOF arms based on multi-wire proportional counters (MWPCs). Each arm has two MWPCs to form a start-stop detection system for TOF measurements. The start detector has an active area of 4 × 4 cm 2 . The stop detector is a two-dimensional position sensitive MWPC with an active area of 16 × 11 cm 2 . Salient features of the MWPCs are the use of reduced sub-millimeter wire pitches of 0.635 and 0.317 mm in the electrodes along with the use of gold plated tungsten wires of diameters 10 and 20 µm. A delay line for position electrodes is prepared using chip inductors and capacitors. Ten different configurations of MWPC were investigated for the start detector, which involved the use of three and four electrode geometries, use of different wire pitches, and use of aluminized mylar for timing electrodes. Performance results close to micro-channel plate detectors have been observed with some designs of MWPC, displaying rise times better than 2 ns with an estimated inherent time resolution of ∼100 ps FWHM. A position resolution of ∼1 mm (FWHM) has been observed. Design features of the MWPCs and their test performance results are described in this article.

An encephalocoele is a spectrum of cranial dysraphism caused due to defective closure of neural tube during early embryonic life, leading to formation of a cerebrospinal fluid (CSF)-filled sac containing brain tissue and meninges, all herniated through a bony defect of the skull. Anterior encephalocoeles, though rare in the Western world, are relatively common in southeast Asia, including some parts of India. Among anterior encephalocoeles, fronto-ethmoidal type is the most common followed by orbital encephalocoeles. Giant encephalocoeles are rare with few published short series, which are mostly located in occipital region. Giant interfrontal encephalocoele through a wide anterior fontanel is the rarest one and is limited to three case reports, including this index case. Here we report a case of giant anterior fontanel encephalocoele in a 20-day-old neonate and discuss various aspects of its management., Competing Interests: There are no conflicts of interest., (Copyright: © 2020 Journal of Pediatric Neurosciences.)

Extradural hematoma (EDH) generally occurs in the site of impact, that is, coup injury site. EDH is associated with fracture of skull in many a times due to direct impact. However, EDH in counter coup site is a rare occurrence. Hardly, yet, 12 cases have been reported including this case. Here, we reported a case of a 22-year-old male of contrecoup acute EDH who had sustained head injury due to fall from bike. Physical examination revealed direct impact at the left occipito-parietal region with laceration of scalp and bruise with transient loss of consciousness at the time of injury. There was no evidence of impact on the right side of his head. Computed tomography scan revealed an EDH in the right fronto-temporal region without any bone fracture on bone windows. On intraoperative exploration, it is found that there was coronal suture diastasis with small subgaleal hematoma and right fronto-temporal extradural hematoma. The evacuation of EDH was done. The patient discharged on 3 rd postoperative day. It can be concluded that direct impact on head causes exactly opposite hit of brain, and compensatory rebound causes a negative pressure in between the layers causing disruption of vessels and potential accumulation of blood. This mechanism mostly favors for acute subdural hematoma due to compact attachment of dura with cranium. However, in this case, diastasis of coronal suture due to transmitted force is the cause of accumulation of blood extradurally in relatively loosely adhered dura in fronto-temporal region where a potential negative pressure space is created by contrecoup injury., Competing Interests: There are no conflicts of interest.

Even if human beings are the most intelligent among all living beings, they are still not immune to attack from wild animals. Human contact with bears has become more frequent as their habitat is being endangered by frequent deforestation. The sloth bear is one of the few bear species found in India, especially in the hilly areas of Southern Odisha. Bears are highly intelligent and omnivorous animals with long claws coupled with powerful shoulder. Here, we describe the tale of a poor tribal male's encounter with a sloth bear resulting in critical injuries to face, scalp, skull bone, with brain matter fungating-out of the skull. We immediately went for debridement of the, bulged-out contused brain matter and opted for delayed repair of scalp defect with antero-lateral thigh free-flap to save him from fatality along with an acceptable cosmetic repair of the defect., Competing Interests: There are no conflicts of interest.

Background: Masson hemangioma is a rare pathologic entity characterized by intravascular papillary endothelial hyperplasia. Although benign, this hemangioma grows to form an expansile compressing mass. This lesion is mostly seen in skin and subcutaneous tissue. Occurrence in the central nervous system is rare. Still rarer is a spinal location with only 5 case reports published to date in the literature., Case Description: A 32-year-old man presented with paraplegia secondary to extradural compression at the T4-5 level. Histopathologic features were consistent with intravascular papillary endothelial hyperplasia, also known as Masson hemangioma. Differential diagnosis, management, and review of literature are discussed in this report., Conclusions: This rare pathology should be in the differential diagnosis when spinal cord compressive myelopathy is encountered., (Copyright © 2016 Elsevier Inc. All rights reserved.)

Background: Subacute subdural hematoma (SASDH) is an entity which is yet to capture the popular imagination among the neurosurgeons. Its management is often equated clinically to that of the chronic subdural hematoma (CSDH). However, their neurological deterioration is usually rapid, which seems to align them with acute subdural hematoma (ASDH). We proceed for their epidemiological evaluation. The advantages of a novel "double barrel technique (DbT)" over the conventional burrhole drainage are also presented., Methods: This retrospective study was conducted on all the patients having clinical and radiological evidence of SASDH, admitted to a tertiary care referral institute, during the period August 2013 to December 2015. Postoperatively, patients were followed-up for 3-24 months., Results: 46.87% of the patients belonged to the 35-54 year age group with a male predominance (3.6:1); 68.7% had a history of alcohol abuse, whereas aspirin users were 25%. 87.5% cases were unilateral, 18.75% were hemispheric, and 46.87% were present on the left side. Altered consciousness (100%) followed by headache (37.5%) were the most common presenting clinical features., Conclusion: SASDH is an uncommon neurosurgical entity (0.89% of traumatic brain injury cases in our study) and mimics both CSDH as well as ASDH. The true incidence of SASDH may have been underestimated due to its clinical imitation with CSDH. This study in a South Asian nation also provides the epidemiological data of this rare neurosurgical entity. Outcome of surgery is good; our retrospective study confirms that "DbT" is an adequate and safe treatment. However, a better designed, randomized control trial will be needed to reinforce our findings.

Thin carbon-backed isotopically enriched 208 Pb targets were required for our experiment aimed to study the reaction dynamics for 48 Ti +  208 Pb system, populating the near super-heavy nucleus 256 Rf, through mass-energy correlation of the fission fragments. Purity and thickness of the targets are of utmost importance in such studies as these factors have strong influence on the measurement accuracy of mass and energy distribution of fission fragments. 208 Pb targets with thickness ranging from 60 μg/cm 2 to 250 μg/cm 2 have been fabricated in high vacuum environment using physical vapor deposition method. Important points in the method are as follows: • 208 Pb was deposited using resistive heating method, whereas carbon (backing foil) deposition was performed by using the electron beam bombardment technique.•Different characterization techniques such as Particle Induced X-ray Emission (PIXE), Energy Dispersive X-Ray Fluorescence (EDXRF) and Rutherford Backscattering Spectrometry (RBS) were used to assert the purity and thickness of the targets.•These targets have successfully been used to accomplish our experimental objectives.

Two large area multistep position sensitive (two dimensional) multiwire proportional counters have been developed for experiments involving study of fission dynamics using general purpose scattering chamber facility at IUAC. Both detectors have an active area of 20x10 cm(2) and provide position signals in horizontal (X) and vertical (Y) planes, timing signal for time of flight measurements and energy signal giving the differential energy loss in the active volume. The design features are optimized for the detection of low energy heavy ions at very low gas pressures. Special care was taken in setting up the readout electronics, constant fraction discriminators for position signals in particular, to get optimum position and timing resolutions along with high count rate handling capability of low energy heavy ions. A custom made charge sensitive preamplifier, having lower gain and shorter decay time, has been developed for extracting the differential energy loss signal. The position and time resolutions of the detectors were determined to be 1.1 mm full width at half maximum (FWHM) and 1.7 ns FWHM, respectively. The detector could handle heavy ion count rates exceeding 20 kHz without any breakdown. Time of flight signal in combination with differential energy loss signal gives a clean separation of fission fragments from projectile and target like particles. The timing and position signals of the detectors are used for fission coincidence measurements and subsequent extraction of their mass, angular, and total kinetic energy distributions. This article describes systematic study of these fission counters in terms of efficiency, time resolution, count rate handling capability, position resolution, and the readout electronics. The detector has been operated with both five electrode geometry and four electrode geometry, and a comparison has been made in their performances.