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The growing demand for wireless communication in biomedical engineering has opened new research frontiers. This paper introduces an innovative miniaturized ( $4\times 9$ mm2) multiple-input multiple-output (MIMO) circularly polarized (CP) implantable antenna for a wireless capsule endoscopy (WCE) system. The presented device features two Hilbert curve-shaped meandered resonators. The space-filling characteristic inherent in the Hilbert curve contributes to miniaturization and bandwidth enhancement of up to 250 MHz to cover possible detuning between diverse organs. Simultaneously, employing the curve’s inherent natural symmetry and adopting an orthogonal port arrangement led to a noteworthy improvement in isolation up to 27 dB with an enhanced gain of −27.9 dBi. Comprehensive simulation analysis of antenna-integrated WCE systems in homogeneous and hetrogenous environments is conducted in the stomach, small intestine, and large intestine. Without the need for an external decoupling structure, the system demonstrated good MIMO characteristics with isolation of 27 dB. A fabricated prototype has been tested in a saline solution and minced pork. A good match between the measured and simulated results has been observed. At both ports, the axial ratio (

This study examines a single-fed, self-isolated, dual-band, 8-element multiple-input multiple-output (MIMO) antenna system for fifth-generation (5G) and beyond-5G (B5G) handsets. The proposed antenna is designed by an innovative composition of two F-shaped slots backed by a slotted ground plane, enabling a dual-band operation in the sub-6 GHz (4.7 to 4.9 GHz, n79) and millimeter wave (mmWave) (28 to 29 GHz, n257) frequency bands. High isolation of >14.4 dB and >25 dB and a high diversity gain of >9.9 dB were achieved at the respective frequency bands without using additional decoupling techniques, exhibiting an efficiency of approximately 90% with high gains of 4.9 and 7.2 dBi at the n79 and n257 bands, respectively. The antenna demonstrates excellent MIMO performance regarding very low envelope correlation coefficient ( $\lt -7.3$ dB and −7 dB). In addition to the safety evaluations, the performance is verified in a realistic mobile device to ensure practical feasibility. The evaluations showed promising results, demonstrating that the proposed design is a suitable, compact, and highly effective MIMO solution for 5G and B5G handsets.

This study presents a novel, compact, diamond-shaped Multiple Input Multiple Output (MIMO) antenna system for 5G wireless communication. The proposed MIMO antenna system encompasses an array configuration, with each array unit comprising two antenna elements. The array elements are then orthogonally oriented making it a dual-port MIMO antenna system. The system is printed on a commercially available Rogers 5880, characterized by a permittivity ( $\varepsilon _{\mathrm {r}}$ ) of 2.2 and a loss tangent (tan( $\delta)$ ) of 0.0009. The overall dimensions of the MIMO antenna system are $26\times 16\times0.254$ mm3, operating in an mm-wave band with a frequency spectrum spanning from 26.2 to 34.2 GHz. The single antenna element exhibited a gain of 3.8 dBi and is then improved up to 7.6 dBi with two elements array arrangement. The system exhibited satisfactory MIMO characteristics with a maximum diversity gain of 10 dB, an envelope correlation coefficient of less than 0.0005, and an impressive 25 dB isolation between the antenna elements. Moreover, the proposed MIMO antenna array consistently maintained a radiation efficiency exceeding 90% across the entire desired frequency spectrum. Measurements were conducted with fabricated prototypes to validate the simulation results and were found in good agreement. The remarkable features of the proposed MIMO antenna system, such as compact size, wide bandwidth, good efficiency, and satisfactory gain values make it a promising candidate for 5G millimeter-wave wireless communication networks.

Abstract Background Radiofrequency ablation (RFA) is one of the treatment options for lung nodules. However, the need for exact delivery of the rigid metal electrode into the center of the target mass often leads to complications or suboptimal results. To overcome these limitations, a concept of conforming electrodes using a flexible material has been tested in this study. Methods A bronchoscopy-guided RFA (CAROL) under a temperature-controlled mode was tested in in-vivo and ex-vivo porcine lungs. Gallium-based liquid metal was used for turning the bronchial tree into temporary RF electrodes. A customized bronchoscopy-guided balloon-tipped guiding catheter (CAROL catheter) was used to make the procedure feasible under fluoroscopy imaging guidance. The computer simulation was also performed to gain further insight into the ablation results. Safety was also assessed including the liquid metal remaining in the body. Results The bronchial electrode injected from the CAROL catheter was able to turn the target site bronchial air pipe into a temporally multi-tined RF electrode. The mean volume of Gallium for each effective CAROL was 0.46 ± 0.47 ml. The ablation results showed highly efficacious and consistent results, especially in the peripheral lung. Most bronchial electrodes were also retrieved by either bronchoscopic suction immediately after the procedure or by natural expectoration thereafter. The liquid metal used in these experiments did not have any significant safety issues. Computer simulation also supports these results. Conclusion The CAROL ablation was very effective and safe in porcine lungs showing encouraging potential to overcome the conventional approaches.

OBJECTIVES This study aimed to determine the future preferences of house officers when choosing a medical speciality. METHODOLOGY The cross-sectional study was conducted from January to June 2023 at three teaching hospitals in Abbottabad. 250 participants were selected as the study sample. The data was collected from house officers on a predesigned, self-structured written questionnaire. The data was analyzed using SPSS version 21. RESULTS Of 250 individuals, 224 met inclusive criteria; 65% (146) were male and 35% (78) were female. The mean age was 25 years ±1.01. The first preference of the house officer was medicine (44% (100), the second was surgery (31.5%) (70), and the third was obstetrics and gynaecology. Among medicine specialities, only 0.9% (02) opt endocrinology and gastroenterology, while among surgical specialities, 0.4% (01) opt urology and 0.9% (02) opt neurosurgery. 150 individuals (70%) planned residency in the future, among whom 47% (106) set a caveat for residency abroad. The most favourite place abroad was the UK, with 42% (45/106). 180 house officers (80%) are satisfied with their academic abilities. CONCLUSION The study revealed that house officers have no awareness of new specialities and are least interested in specialities like endocrinology, gastroenterology, neurosurgery, and urology. In contrast, no influence was noted toward specialities like haematology, public health and community medicine. Most students are satisfied with their medical education but plan to do their residency abroad.

This paper aims to systematically assess the local radial basis function collocation method, structured with multiquadrics (MQs) and polyharmonic splines (PHSs), for solving steady and transient diffusion problems. The boundary value test involves a rectangle with Dirichlet, Neuman, and Robin boundary conditions, and the initial value test is associated with the Dirichlet jump problem on a square. The spectra of the free parameters of the method, i.e., node density, timestep, shape parameter, etc., are analyzed in terms of the average error. It is found that the use of MQs is less stable compared to PHSs for irregular node arrangements. For MQs, the most suitable shape parameter is determined for multiple cases. The relationship of the shape parameter with the total number of nodes, average error, node scattering factor, and the number of nodes in the local subdomain is also provided. For regular node arrangements, MQs produce slightly more accurate results, while for irregular node arrangements, PHSs provide higher accuracy than MQs. PHSs are recommended for use in diffusion problems that require irregular node spacing.

The integration of sub-6-GHz and millimeter-wave (mm-wave) bands has become an important issue for future fifth generation (5G) wireless communications owing to their large frequency ratios. This paper proposes a compact-size dual-function antenna operating at 3.5 GHz and the mm-wave band (28 GHz) for 5G mobile applications using a frequency reconfigurability technique. The proposed antenna comprises a microstrip patch linked with a meandered radiating structure through a radio frequency PIN diode to achieve frequency reconfigurability between the two bands. A significant size reduction up to 15.3 mm × 7.2 mm × 0.508 mm for the proposed antenna was achieved using a meandered line structure and truncated ground plane. To enhance the functionality, 8 × 8 multiple-input multiple-output (MIMO) with possible long- and short-edge antenna placement configurations were demonstrated. The system exhibited satisfactory MIMO characteristics with wide decoupling -10 dB bandwidths of 7.4% and 4.8% at the low- and high-frequency bands, respectively, without utilizing any external decoupling structure. The simulated results were validated using fabricated prototypes, and good agreement was observed. Additionally, a safety analysis based on the specific absorption rate and power density at the prescribed frequency bands was conducted using a realistic human model, and the results were found to be in accordance with the safety guidelines. Owing to the integration of sub-6-GHz and mm-wave bands in a single compact structure with a large frequency ratio and good MIMO performance, the proposed antenna system is suitable for future 5G mobile handheld devices.

In the present research article, a modified analytical method is applied to solve time-fractional telegraph equations. The Caputo-operator is used to express the derivative of fractional-order. The present method is the combination of two well-known methods namely Mohan transformation method and Adomian decomposition method. The validity of the proposed technique is confirmed through illustrative examples. It is observed that the obtained solutions have strong contact with the exact solution of the examples. Moreover, it is investigated that the present method has the desired degree of accuracy and provided the graphs closed form solutions of all targeted examples. The graphs have verified the convergence analysis of fractional-order solutions to integer-order solution. In conclusion, the suggested method is simple, straightforward and an effective technique to solve fractional-order partial differential equations.

Species are the cornerstone in many domains of biology research, which make accurate species delimitation critically important. In this study, the systematics and biogeography of the Hyla chinensis group were analyzed based on phylogeny, species delimitation, and ancestral area reconstruction methods. The phylogenetic results showed that six specific clusters existed in the H. chinensis group. Bayesian Phylogenetics and Phylogeography (BPP) analysis indicated that six distinct species exist due to the high probability values (>0.95), which were also supported by the Bayes factor (BF) analysis. The divergence time of the H. chinensis group was estimated to date back to 18.84 million years ago (Mya) in the early Miocene. Combining the results of ancestral area reconstruction, the H. chinensis group might have originated from Guangxi-Hainan, then spread eastwardly and reached Nanling Mountains, Wuyi Mountains, Huangshan Mountain, and Taiwan. In right-about colonization, it was gradually extended to the Yunnan-Guizhou Plateau, Sichuan Basin, Qinling Mountains, and Dabie Mountains. Considering the geological movement from early Miocene to Pliocene, the colonization pattern of the H. chinensis group may be closely related to the progressive uplift of the Qinghai-Tibetan Plateau (QTP) and historical climate change. Our study provided evidence for species delimitation and speciation process within the H. chinensis group. Our study supported the hypothesis that the evolutionary divergence in this species group was a consequence of the progressive uplift of the QTP and environmental change.

The high-altitude region of Asia is prone to natural resource degradation caused by a variety of natural and anthropogenic factors that also threaten the habitat of critical top predator species, the snow leopard (Panthera uncia). The snow leopard’s landscape encompasses parts of the twelve Asian countries and is dominated by pastoral societies within arid mountainous terrain. However, no investigation has assessed the vulnerability and pathways towards long-term sustainability on the global snow leopard landscape scale. Thus, the current study reviewed 123 peer-reviewed scientific publications on the existing knowledge, identified gaps, and proposed sustainable mitigation options for the longer term and on larger landscape levels in the range countries. The natural resource degradation in this region is caused by various social, economic, and ecological threats that negatively affect its biodiversity. The factors that make the snow leopard landscapes vulnerable include habitat fragmentation through border fencing, trade corridor infrastructure, non-uniform conservation policies, human–snow leopard conflict, the increasing human population, climatic change, land use and cover changes, and unsustainable tourism. Thus, conservation of the integrated Socio-Ecological System (SES) prevailing in this region requires a multi-pronged approach. This paper proposes solutions and identifies the pathways through which to implement these solutions. The prerequisite to implementing such solutions is the adoption of cross-border collaboration (regional cooperation), the creation of peace parks, readiness to integrate transnational and cross-sectoral conservation policies, a focus on improving livestock management practices, a preparedness to control human population growth, a readiness to mitigate climate change, initiating transboundary landscape-level habitat conservation, adopting environment-friendly trade corridors, and promoting sustainable tourism. Sustainable development in this region encompasses the political, social, economic, and ecological landscapes across the borders.

Orthriophis moellendorffi (Colubridae, Serpentes) mainly inhabits in an altitude of 50–300 meters in south China and also in Vietnam. The complete mitogenome sequence of O. moellendorffi is 17,191 bp in length, including 13 protein-coding genes, 22 tRNA genes, 2 rRNA genes, and a D-loop region. The base composition of mitogenome was 35.4%A, 26.2% C, 12.3% G, and 26.1% T. The ND6 subunit gene and eight tRNA genes are encoded on the L-strand, the others are encoded on the H-strand.

Habitat loss and degradation are among the leading causes of local extinctions, so it is crucially important to preserve and restore the remaining critical habitat increasingly critical to conserve biodiversity. However, mechanisms driving species extinction often begin with habitat loss and seldom are well understood, which is greatly limits our ability to mitigate their impacts. The Chinese Alligator (Alligator sinensis) is a critically endangered crocodilian, which is narrowly distributed in very small six regions of Anhui province, China. In the present study, we used 9 nuclear microsatellite loci genotyped across the taxon's distribution area to investigate genetic variation and population demography in A. sinensis. The Chinese Alligator showed unusually low levels of genetic diversity (Na, 5.44; Ne, 1.97; He, 0.47) based on 793 individuals. Msvar analyses found recent signals of population decline reflecting a bottleneck (an approximately 9-fold decrease) about 25,000 years ago. Ecological niche modelling indicated that the habitat area has declined (about 8–15 fold) for A. sinensis when compared with that under different historical climatic conditions. Our results indicated that population decline and habitat loss in critically endangered Chinese Alligators may have acted as intrinsic and extrinsic factors that have impacted the current status of A. sinensis. In addition, these two unfavorable factors may have also directly contributed to a reduction in the genetic diversity of A. sinensis. Keywords: Alligator sinensis, Genetic diversity, Population demography, Niche reconstruction

Mostly, it is very difficult to obtained the exact solution of fractional-order partial differential equations. However, semi-analytical or numerical methods are considered to be an alternative to handle the solutions of such complicated problems. To extend this idea, we used semi-analytical procedures which are mixtures of Laplace transform, Shehu transform and Homotopy perturbation techniques to solve certain systems with Caputo derivative differential equations. The effectiveness of the present technique is justified by taking some examples. The graphical representation of the obtained results have confirmed the significant association between the actual and derived solutions. It is also shown that the suggested method provides a higher rate of convergence with a very small number of calculations. The problems with derivatives of fractional-order are also solved by using the present method. The convergence behavior of the fractional-order solutions to an integer-order solution is observed. The convergence phenomena described a very broad concept of the physical problems. Due to simple and useful implementation, the current methods can be used to solve problems containing the derivative of a fractional-order.

In the present research work, a newly developed technique which is known as variational homotopy perturbation transform method is implemented to solve fractional-order acoustic wave equations. The basic idea behind the present research work is to extend the variational homotopy perturbation method to variational homotopy perturbation transform method. The proposed scheme has confirmed, that it is an accurate and straightforward technique to solve fractional-order partial differential equations. The validity of the method is verified with the help of some illustrative examples. The obtained solutions have shown close contact with the exact solutions. Furthermore, the highest degree of accuracy has been achieved by the suggested method. In fact, the present method can be considered as one of the best analytical techniques compared to other analytical techniques to solve non-linear fractional partial differential equations.

In the present article, we consider certain subfamilies of analytic functions connected with the cardioid domain in the region of the unit disk. The purpose of this article is to investigate the estimates of the third Hankel determinant for these families. Further, the same bounds have been investigated for two-fold and three-fold symmetric functions.

Variation in litter size (LS) in sheep is linked to genetic factors, including the Zona pellucida-3 (ZP3) gene, which plays a role in ovine reproductive processes. This study examined the association between ZP3 gene variations and LS in Kari sheep. Two groups of 160 Kari ewes were analysed: one consistently producing singletons and another producing twins, with occasional triplets. Additionally, Madakhlasht sheep, which sometimes produce twins, and Balkhi sheep, which produce only singletons, were used as references. The entire ZP3 gene was amplified using PCR and sequenced at 30× with Next Generation Sequencing. Bioinformatics analysis identified 70 variants across the three breeds, located in upstream regions, introns, and exons. Notably, two point mutations and a six-nucleotide insertion were found upstream of the initiation codon in twin-producing Kari ewes, potentially affecting ZP3 expression and LS. Two missense mutations (I101L in exon 1 and R408H in exon 8) were heterozygous in twin-producing Kari ewes but homozygous in other groups, correlating with LS. Protein modelling suggested that the I101L mutation alters the binding site, potentially impacting protein function. These findings indicate that ZP3 gene variations influence reproductive efficiency and LS in sheep, with specific variants serving as potential markers for selective breeding to enhance LS.

This paper presents an effort pertaining to the simulation of the future production in Pakistan of different primary energy resources, i.e., coal, natural gas and crude oil, thereby constructing Hubbert peaks. In this context, the past 45 years’ production data of primary energy resources of Pakistan have been analyzed and simulated using a generic STELLA (Systems Thinking, Experimental Learning Laboratory with Animation) model. The results show that the Hubbert peak of Pakistan’s crude oil production has been somehow already achieved in 2013, with the highest production of 4.52 million toe, which is 1.51 times the production in 2000. Similarly, the natural gas peak production is expected in 2024 with a production of 32.70 million toe which shall be 1.96-fold the extraction of the resource in the year 2000. On the other hand, the coal production in the country has been historically very low and with a constant production rate that is gradually picking up, the peak production year for the coal is anticipated to be in the year 2080 with an estimated production of 134.06 million. Based on the results of this study, which provide a greater understanding of future energy patterns, it is recommended that an energy security policy be devised for the country to ensure sustained supplies in the future.

This study presents an innovative wirelessly powered stent rectenna system for endovascular aneurysm repair (EVAR), targeting abdominal aortic aneurysm (AAA) treatment. The system includes an on‐body flexible transmitter (Tx) antenna and an in‐body rectifier‐integrated stent receiver (Rx) antenna, operating in the industrial, scientific, and medical (ISM) band of 868 MHz. The Rx stent antenna, made from a biocompatible nylon‐coated metallic wire, ensures mechanical stretchability, biocompatibility, and precise current distribution. The flexible Tx antenna is designed for wearable use. A miniaturized rectifier on flexible polyimide, coated with biocompatible polydimethylsiloxane, converts received power into DC energy. The EVAR stent system's performance is validated through measurements using a saline‐filled American Society for Testing and Materials (ASTM) phantom. Magnetic resonance imaging (MRI) compatibility studies using Sim4Life simulations assess potential heating and image artifacts, confirming the proposed stent's MRI suitability. Wireless power transfer experiments demonstrate reliable power delivery to the Rx in various real‐world scenarios, achieving a power transfer efficiency of 3.6% at 18 cm inside the phantom. The flexible rectifier shows a peak efficiency of 87% at 15 dBm input power. The proposed system's exceptional performance and efficiency highlight its potential for effectively wirelessly powering advanced AAA stents. [ABSTRACT FROM AUTHOR]