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Land Use and Land Cover (LULC) change has evolved as a central force behind environmental challenges and has gained great acknowledgment for its wide-ranging effects on biodiversity and ecosystem services. Mountains, including the mountainous belts of Pakistan, are particularly vulnerable to alterations in LULC resulting from deforestation and other anthropogenic activities. These changes have profound repercussions on the socio-ecological and biophysical environments of mountains. This research aims to investigate the spatiotemporal changes in LULC in the Swat River Basin (SRB), Eastern Hindu Kush, Pakistan. Assessments of LULC changes are crucial for gaining an in-depth understanding, formulating policy guidelines, and implementing conservation practices to address the environmental challenges faced by mountainous areas. The study is based on remotely sensed data and Geographic Information System (GIS) analysis. The temporal span (1988–2018) is divided into three periods and based on ten years interval, Landsat Satellite Images were acquired for 1988, 1998, 2008 and 2018. These images were processed and classified in ArcGIS 10.8. The analysis indicates varying trends in LULC changes over three periods. Forest cover increased by 52.5% in period 1 as a result of social forestry project but declined in periods 2 (-12.8%) and 3 (-18.8%). Contrarily, rangeland decreased by 63.9% in period 1 but grew in periods 2 (71.1%) and 3 (15.5%). Built-up areas expanded by 280%, barren land by 47%, agricultural land by 14.3%. However, snow cover consistently decreased. These alterations are mainly the result of bio-physical impacts, which highlight the urgent need for sustainable land management to mitigate the environmental impact of human activities. [ABSTRACT FROM AUTHOR]

Background and Objective: Thyroid imaging reporting and data system (TI-RADS) is developed to determine the risk of malignancy in patients with thyroid nodules. The aim of this study was to determine the diagnostic accuracy of TI-RADS classification for diagnosing malignant thyroid nodules taking Fine needle aspiration cytology (FNAC) as a gold standard in the local population. Methods: In this cross-sectional validation study, 201 patients presenting with thyroid nodules at the Department of Radiology, Bakhtawar Amin Hospital Multan, Pakistan from July 2020 to December 2020 were included. In all patients, thyroid nodules were evaluated on grey scale (B-mode) modality. TI-RADS score was calculated for each patient. Patients with TI-RADS score 4 and 5 were labelled as having malignant nodules. After that FNAC samples were taken and sent for histopathologic evaluation of thyroid nodules. The sensitivity, specificity, positive predictive value (PPV), and negative predictive value (NPV) of TI-RADS taking FNAC as a gold standard were determined. Results: The mean age of the patients was 47.8 ± 4.5 years; there were 129 (67.2%) women and 72 (35.82%) men. There were 42 patients who tested true positive and 36 patients tested false positive and 12 patients were false negative and 111 patients true negative. The TIRADS sensitivity was 77.8%, specificity was 75.5%, PPV was 53.8%, and NPV 90.2%. the diagnostic accuracy was 76.1%. Conclusion: Differentiating benign thyroid nodules from malignant using the TI-RADS score has a high diagnostic accuracy. Our study results support the TIRADS as a first-line imaging evaluation for diagnosis of thyroid malignancy.

State-of-the-art semiconducting aluminum nitride (AlN) films were characterized by cathodoluminescence (CL) spectroscopy in the range of 200–500 nm in an attempt to identify the energy levels within the bandgap and their associated defects. Near-band edge emission (around 206 nm) and high-intensity peaks centered in the near UV range (around 325 nm) are observed for both n- and p-type AlN films. The near UV peaks are potentially associated with oxygen contamination in the films. The p-type AlN films contain at least two unidentified peaks above 400 nm. Assuming that the dopant concentration is independent of compensation (i.e., in the perfect doping limit), three effective donor states are found from Fermi–Dirac statistics for Si-doped AlN, at ∼0.035, ∼0.05, and ∼0.11 eV. Similarly, a single effective acceptor energy of ∼0.03–0.05 eV (depending on the degeneracy factory considered) was found for Be doped AlN. CL investigation of doped AlN films supports claims that AlN may be a promising optoelectronic material, but also points to contaminant mitigation and defect theory as major areas for future study. [ABSTRACT FROM AUTHOR]

We report MOCVD-grown Al0.87Ga0.13N/Al0.64Ga0.36N metal-oxide-semiconductor-heterojunction-field-effect-transistors on single crystal bulk AlN substrate. As compared to control devices on AlN template, thermal impedance for devices on single crystal AlN decreased to 1/3 from 31 to 10 K mm W−1, comparable to SiC and copper heat-sinks. This represents a significant thermo-electric co-design advantage over other semiconductors. As a result, the peak drain saturation current increased from 410 to 610 mAmm−1. A 3-terminal breakdown field of 3.7 MV cm−1 was measured, which to date represents state-of-the-art performance for devices with similar Al x Ga1− x N-channel composition. This translates to a measured Baliga figure of merit of 460 MWcm−2. [ABSTRACT FROM AUTHOR]

Microfluidics technology has not impacted the delivery and accessibility of point-of-care health services, like diagnosing infectious disease, monitoring health or delivering interventions. Most microfluidics prototypes in academic research are not easy to scale-up with industrial-scale fabrication techniques and cannot be operated without complex manipulations of supporting equipment and additives, such as labels or reagents. We propose a label- and reagent-free inertial spiral microfluidic device to separate red blood, white blood and dendritic cells from blood fluid, for applications in health monitoring and immunotherapy. We demonstrate that using larger channel widths, in the range of 200 to 600 µm, allows separation of cells into multiple focused streams, according to different size ranges, and we utilize a novel technique to collect the closely separated focused cell streams, without constricting the channel. Our contribution is a method to adapt spiral inertial microfluidic designs to separate more than two cell types in the same device, which is robust against clogging, simple to operate and suitable for fabrication and deployment in resource-limited populations. When tested on actual human blood cells, 77% of dendritic cells were separated and 80% of cells remained viable after our assay.

Recent advances in inertial microfluidics designs have enabled high throughput, label-free separation of cells for a variety of bioanalytical applications. Various device configurations have been proposed for binary separation with a focus on enhancing the separation distance between particle streams to improve the efficiency of separate particle collection. These configurations have not demonstrated scaling beyond 3 particle streams either because the channel width is a constraint at the collection outlets or particle streams would be too closely spaced to be collected separately. We propose a method to design collection outlets for inertial focusing and separation devices which can collect closely-spaced particle streams and easily scale to an arbitrary number of collection channels without constraining the outlet channel width, which is the usual cause of clogging or cell damage. According to our approach, collection outlets are a series of side-branching channels perpendicular to the main channel of egress. The width and length of the outlets can be chosen subject to constraints from the position of the particle streams and fluidic resistance ratio computed from fluid dynamics simulations. We show the efficacy of this approach by demonstrating a successful collection of upto 3 particle streams of 7μm, 10μm and 15μm fluorescent beads which have been focused and separated by a spiral inertial device with a separation distance of only 10μm -15μm. With a throughput of 1.8mL/min, we achieved collection efficiency exceeding 90% for each particle at the respective collection outlet. The flexibility to use wide collection channels also enabled us to fabricate the microfluidic device with an epoxy mold that was created using xurography, a low cost, and imprecise fabrication technique.

Master mold fabricated using micro milling is an easy way to develop the polydimethylsiloxane (PDMS) based microfluidic device. Achieving high-quality micro-milled surface is important for excellent bonding strength between PDMS and glass slide. The aim of our experiment is to study the optimal cutting parameters for micro milling an aluminum mold insert for the production of a fine resolution microstructure with the minimum surface roughness using conventional computer numerical control (CNC) machine systems; we also aim to measure the bonding strength of PDMS with different surface roughnesses. Response surface methodology was employed to optimize the cutting parameters in order to obtain high surface smoothness. The cutting parameters were demonstrated with the following combinations: 20,000 rpm spindle speed, 50 mm/min feed rate, depth of cut 5 µm with tool size 200 µm or less; this gives a fine resolution microstructure with the minimum surface roughness and strong bonding strength between PDMS–PDMS and PDMS–glass.

Highly sensitive and specific pathogen diagnosis is essential for correct and timely treatment of infectious diseases, especially virulent strains, in people. Point-of-care pathogen diagnosis can be a tremendous help in managing disease outbreaks as well as in routine healthcare settings. Infectious pathogens can be identified with high specificity using molecular methods. A plethora of microfluidic innovations in recent years have now made it increasingly feasible to develop portable, robust, accurate, and sensitive genomic diagnostic devices for deployment at the point of care. However, improving processing time, multiplexed detection, sensitivity and limit of detection, specificity, and ease of deployment in resource-limited settings are ongoing challenges. This review outlines recent techniques in microfluidic genomic diagnosis and devices with a focus on integrating them into a lab on a chip that will lead towards the development of multiplexed point-of-care devices of high sensitivity and specificity.