Hand-held System Research Articles

Reality and Beyond: Proxemics as a Lens for Designing Handheld Collaborative Augmented Reality

Augmented Reality (AR) has shown great potential for supporting co-located collaboration. Yet, it is rarely articulated in the design rationales of AR systems that they promote a certain socio-spatial configuration of the users. Learning from proxemics, we argue that such configurations enable and constrain different co-located spatial behaviors with consequences for collaborative activities. We focus specifically on enabling different collaboration styles via the design of Handheld Collaborative Augmented Reality (HCAR) systems. Drawing upon notions of proxemics, we show how different HCAR designs enable different socio-spatial configurations. Through a design exploration, we demonstrate interaction techniques to expand on the notion of collaborative coupling styles by either deliberately designing for aligning with physical reality or going beyond. The main contributions are a proxemics-based conceptual lens and vocabulary for supporting interaction designers in being mindful of the proxemic consequences when developing handheld multi-user AR systems.

Robotic-assisted total knee arthroplasty improved component alignment in the coronal plane compared with navigation-assisted total knee arthroplasty: a comparative study.

The purpose of this study was to directly compare implant placement accuracy and postoperative limb alignment between robotic-assisted total knee arthroplasty and navigation-assisted total knee arthroplasty. This retrospective case-control study included a consecutive series of 182 knees (robotic-assisted group, n = 103 knees; navigation-assisted group, n = 79). An image-free handheld robotic system (NAVIO) or an image-free navigation system (Precision N) was used. Component and limb alignment were evaluated on three-dimensional computed tomography scans and full-length standing anterior-posterior radiographs. We compared the errors between the final intraoperative plan and the postoperative coronal and sagittal alignment of the components and the hip-knee-ankle angle between the two groups. The orientation of the femoral and tibial components in the coronal plane were more accurate in the robotic-assisted group than in the navigation-assisted group (p < 0.05). There was no significant difference in the orientation of the femoral and tibial component in the sagittal plane between the two groups. There were fewer outliers in the tibial coronal plane in the robotic-assisted group (p < 0.05). There was also no significant difference in the frequency of outlying values for coronal or sagittal alignment of the femoral component or sagittal alignment of the tibial component or the hip-knee-ankle angle between the two groups. Robotic-assisted total knee arthroplasty using a handheld image-free system improved component alignment in the coronal plane compared with total knee arthroplasty using an image-free navigation system. Robotic surgery helps surgeons to achieve personalised alignment that may result in better clinical outcomes.

Remote sensing continuity: a comparison of HTP platforms and potential challenges with field applications.

In an era of climate change and increased environmental variability, breeders are looking for tools to maintain and increase genetic gain and overall efficiency. In recent years the field of high throughput phenotyping (HTP) has received increased attention as an option to meet this need. There are many platform options in HTP, but ground-based handheld and remote aerial systems are two popular options. While many HTP setups have similar specifications, it is not always clear if data from different systems can be treated interchangeably. In this research, we evaluated two handheld radiometer platforms, Cropscan MSR16R and Spectra Vista Corp (SVC) HR-1024i, as well as a UAS-based system with a Sentera Quad Multispectral Sensor. Each handheld radiometer was used for two years simultaneously with the unoccupied aircraft systems (UAS) in collecting winter wheat breeding trials between 2018-2021. Spectral reflectance indices (SRI) were calculated for each system. SRI heritability and correlation were analyzed in evaluating the platform and SRI usability for breeding applications. Correlations of SRIs were low against UAS SRI and grain yield while using the Cropscan system in 2018 and 2019. Dissimilarly, the SVC system in 2020 and 2021 produced moderate correlations across UAS SRI and grain yield. UAS SRI were consistently more heritable, with broad-sense heritability ranging from 0.58 to 0.80. Data standardization and collection windows are important to consider in ensuring reliable data. Furthermore, practical aspects and best practices for these HTP platforms, relative to applied breeding applications, are highlighted and discussed. The findings of this study can be a framework to build upon when considering the implementation of HTP technology in an applied breeding program.

Hybrid spiral scanning in a double-clad fiber-based handheld confocal scanning light ophthalmoscope.

High-speed, accessible, and robust in vivo imaging of the human retina is critical for screening of retinal pathologies, such as diabetic retinopathy, age-related macular degeneration, and others. Scanning light ophthalmoscopy (SLO) is a retinal imaging modality that produces digital, en face images of the human retina with superior image gradability rates when compared to the current standard of care in screening for these diseases, namely the flood-illumination handheld fundus camera (HFC). However, current-generation commercial SLO systems are mostly tabletop devices, limiting their accessibility and utility in screening applications. Moreover, most existing SLO systems use raster scan patterns, which are both inefficient and lead to undesired subject gaze drift when used with visible or pseudo-visible illumination. Non-raster scan patterns, especially spiral scanning as described herein, promise advantages in both scan efficiency and reduced subject eye motion. In this work, we introduce a novel "hybrid spiral" scan pattern and the associated hardware design and real-time image reconstruction techniques necessary for its implementation in an SLO system. Building upon this core hybrid spiral scanning SLO (HSS-SLO) technology, we go on to present a complete handheld HSS-SLO system, featuring a fiber-coupled portable patient interface which leverages a dual-clad fiber (DCF) to form a single-path optical topology, thus ensuring mechanically robust co-alignment of illumination and collection apertures, a necessity for a handheld system. The feasibility of HSS-SLO for handheld, in vivo imaging is demonstrated by imaging eight human volunteers.

Comparing an imageless hand-held robotic-assisted system versus conventional technique for component positioning and early clinical outcomes in total knee arthroplasty.

This study aimed to examine the component positioning and early clinical outcomes in total knee arthroplasty (TKA) using an imageless hand-held robotic-assisted system compared with those without robotics. Component positioning, hip-knee-ankle angle (HKA), and clinical outcome 1-year postoperatively were compared between 40 patients who underwent TKA with Navio (robot group) and 40 control patients who underwent TKA with a jig-based technique (manual group). The clinical outcomes evaluated were range of motion and the 2011 Knee Society Score. Implantation errors in the coronal and sagittal alignments were significantly fewer in the robotic group than in the manual group. All knees in the robotic group achieved component positions within 3°. However, the HKA and clinical outcomes did not differ between the groups. Although the accuracy of implantation in the robotic group was superior to that in the manual group, the clinical outcomes were similar.

Applications of indocyanine green (ICG) fluorescence technology in open surgery: preliminary experience in pediatric surgery.

Indocyanine green fluorescence technology (ICG) in pediatric minimally invasive surgery has undergone an important improvement in the last 5 years. However, its use in open surgery is still limited. In this paper, we aim to report our preliminary experience with Rubina® lens ICG fluorescence technology in combination with the IMAGE1 S™ system from KARL STORZ in open excision of masses in children. The records of 18 patients undergoing open surgery for head, neck and thorax masses between September and November 2022 were retrospectively reviewed. Rubina® lens ICG fluorescence technology system was used in all the cases. In 10 cases we adopted the holding arm system and in 8 cases the hand-held technique. Data about patients' demographics, surgery and outcomes were collected and analyzed through the following criteria: mass localization, intraoperative time (min), ICG administration (ml), intraoperative complications, postoperative complications. A total of 18 patients were operated: 4 thyroglossal duct cysts, 3 supraorbital cysts, 2 neck masses, 2 pre-auricular and 2 scalp cysts, 2 gynecomastias, 2 lymphangiomas, 1 nose mass. In all the cases, intralesional injection of 0.5-1 ml of ICG solution was performed peri-operatively. Mean operative time was 58.4 min (35-134 min). Postoperative complications included seroma formation in 2 cases. Surgical pathology reports confirmed complete mass excision in all the cases. Based on our preliminary experience, ICG fluorescence guided surgery using Rubina® lens system was very helpful also in open surgery procedures. Rubina® lens system permits to have a very low complication rate, a time-saving surgery, a real time reliability of anatomic structures and an excellent clinical safety. In our experience, holding arm system seems more comfortable than hand-held system. However, further cases need to be performed to evaluate the exact role and to identify new indications of this technique in open pediatric surgical procedures.

Design, modeling, and initial testing of a multi-volume neutron spectrometer

A detector system for neutron spectroscopy and imaging was modeled in Monte Carlo N-Particle transport code (MCNP) to examine the possibility of incident neutron energy measurement (spectroscopy) from an incident direction (imaging) in a hand-held detector system. Experiments using a Pu–Be (plutonium beryllium) neutron source were also conducted. The system is composed of three separate scintillation materials; a hydrogenous neutron scintillation material (BC-501A) and Cs2LiYCl6:Ce (CLYC) separated by Lu2(1-x)Y2xSiO5(LYSO). Light production location and magnitude would be collected using multiple silicon-based photo-multiplier arrays, allowing for spectroscopy and imaging of incident neutrons. Modeled neutron interaction criteria are collected and cataloged through the particle tracking supplemental code (PTRAC) of MCNP 6.2 for analog interactions. Implementing classical neutron kinematics and capture-gated time-of-flight, simulations show that neutron energy is measurable in experiment and that there is position sensitivity to be realized in experiment with the proposed detection architecture. The modeled design was experimentally evaluated with a Pu–Be source, confirming that the spectroscopic capabilities of the detector are functional and closely match the modeled expectation. In this work, we direct our attention to neutron spectroscopy, but the imaging capabilities will be addressed in further work.

Portable manipulation system for commercial robotic surgery forceps.

Transition from the utilisation of traditional instruments to new robotic methodologies in surgical operations occurs rapidly. Although the implementation of these methodologies to classical surgery operations is advantageous due to increased precisions and enhanced motion capabilities of robotic systems, overall worldwide accessibility and adaptation are still limited due to high equipment costs and special infrastructure requirements. The design of four degrees of freedom low cost, compact and portable manipulation system was proposed to allow the utilisation of commercial robotic surgery forceps like a conventional laparoscopy instrument without the necessity of bulky manipulation systems. The structural design of the system was carried out along with necessary kinematic and coupled motion analysis. Prototypes were constructed. Hardware verification of the system was executed using implemented control methodology. The proposed design successfully demonstrated the advantages of multi degree of freedom robotic surgery forceps in a portable handheld system compared to classical laparoscopy instruments.

Integration of Ordered Mesoporous Carbon Spheres-Based Ion-Sensitive Electrodes With Flexible Organic Field-Effect Transistors for Multiplexed Ion Sensing

In the path towards the integration of flexible organic field-effect transistors (OFETs) into the construction of manufactured-on-demand ion-sensors, it is still challenging to obtain high stability and sensitivity as required by high detection accuracy, especially for a multi-sensing system. In this work, ordered mesoporous carbon (OMC) spheres with high surface area and super-hydrophobicity were synthesized and introduced as ion-to-electron transducer layer to improve the sensitivity and stability of Na <sup xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">+</sup> and K <sup xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">+</sup> ion-sensitive electrodes (ISEs). High-performance low-voltage (< 3 V) operated ion-sensitive OFETs (ISOFETs) were further fabricated by on-chip low-temperature packaging of the developed ISEs and OFETs. A three-channel multiplexed flexible sensing tag with improved detection accuracy was demonstrated in a hand-held circuit readout system. This ISOFET sensor has great potential in multiplexed sensing systems and will significantly improve efficiency and accuracy in the field of biochemical analysis.

A smartphone-integrated imaging device for measuring nitrate and phosphate in soil and water samples

This research presents a smartphone-integrated imaging device to detect nitrate (NO3–) and phosphate (PO43-) in soil and water samples for agricultural input management and environmental pollution monitoring. This low-cost and field-deployable device uses a smartphone with a digital camera to take a color photograph of the extracted solution under test. The sensing principle is based on the standard colorimetric phenoldisulfonic acid and ascorbic acid methods for NO3– and PO43- in soil and water samples, respectively. A 3D printed device that houses the sensor's optical source and other optical components is coupled to the phone's built-in rear camera and turned into a compact handheld system. An android application, 'SMART NP,' is also developed to quantify the concentrations of NO3– and PO43- in soil and water samples using the Value (V) component of the Hue Saturation and Value (HSV) color space model. The results obtained with the proposed device were comparable to laboratory-grade spectrophotometer data. The limit of detection of the device for NO3– in soil, NO3– in water, PO43- in soil, and PO43- in water were calculated as 0.1 mg L-1, 0.07 mg L-1, 0.001 mg L-1, and 0.02 mg L-1, respectively, with good accuracy (≤1% bias) and precision (∼2% residual standard deviation). The device exhibited a sensitivity of 0.17 mg L-1, 0.12 mg L-1, 0.026 mg L-1, and 0.49 mg L-1 for NO3– in soil, NO3– in water, PO43- in soil, and PO43- in water, respectively. Overall, this sensing device has the potential to assist farmers or scientists in easily measuring NO3– and PO43- concentrations in soil and water media, without the need for laboratory equipment.

High degree of alignment precision associated with total knee arthroplasty performed using a surgical robot or handheld navigation.

The purpose of this study was to compare the precision of bony resections during total knee arthroplasty (TKA) performed using different computer-assisted technologies. Patients who underwent a primary TKA using an imageless accelerometer-based handheld navigation system (KneeAlign2®, OrthAlign Inc.) or computed tomography-based large-console surgical robot (Mako®, Stryker Corp.) from 2017 to 2020 were retrospectively reviewed. Templated alignment targets and demographic data were collected. Coronal plane alignment of the femoral and tibial components and tibial slope were measured on postoperative radiographs. Patients with excessive flexion or rotation preventing accurate measurement were excluded. A total of 240 patients who underwent TKA using either a handheld (n = 120) or robotic (n = 120) system were included. There were no statistically significant differences in age, sex, and BMI between groups. A small but statistically significant difference in the precision of the distal femoral resection was observed between the handheld and robotic cohorts (1.5° vs. 1.1° difference between templated and measured alignments, p = 0.024), though this is likely clinically insignificant. There were no significant differences in the precision of the tibial resection between the handheld and robotic groups (coronal plane 0.9° vs. 1.0°, n.s.; sagittal plane 1.2° vs. 1.1°, n.s.). There were no significant differences in the rate of overall precision between cohorts (n.s.). A high degree of component alignment precision was observed for both imageless handheld navigation and CT-based robotic cohorts. Surgeons considering options for computer-assisted TKA should take other important factors, including surgical principles, templating software, ligament balancing, intraoperative adjustability, equipment logistics, and cost, into account. III.

RESEARCH ON THE 3D DOCUMENTATION SYSTEM OF CLASSICAL CHINESE GARDENS IN SCENIC AREAS – TAKING KUNSHAN SUIYUAN AS AN EXAMPLE

Abstract. Classical Chinese gardens built in scenic areas have characteristics in rich scales, multi-type elements, and a complex development history. Due to the designed landscape characteristics of "hidden the garden in bigger landscapes", it is often difficult to obtain high-quality heritage information through traditional surveying approaches. The aim of this research is to establish a digital 3D documentation technology system for the classical gardens in scenic areas. Suiyuan Garden, a classical Chinese garden with a history of more than 300 years, was used as a case study. We have integrated UAV low-altitude photogrammetry, handheld laser scanning, ground-mounted laser scanning, macro structured light scanning and other technologies to obtain the 3D data, and to build a digital twin by developing the technical workflow and data standard. The innovation of the research lies in: 1) We used a variety of digital mapping methods to record the pattern between the garden and the surrounding landscape; 2) We adopted a combination of handheld and ground-mounted laser scanning systems to build spatial structures and better cover the ground spaces; 3) We established a workflow for the conversion from point cloud to mesh model for different garden features, which can improve the usability of 3D heritage information; 4) We used the 3D cultural heritage modelling approach to improve the standards of the digital conservation of historic plants. The outcomes of this research could be used as the basis for the construction of Historic Landscape Information Model (HLIM) in the near future.

Handheld wide-field fluorescence lifetime imaging system based on a distally mounted SPAD array.

In this work a handheld Fluorescent Lifetime IMaging (FLIM) system based on a distally mounted < 2 mm2 128 × 120 single photon avalanche diode (SPAD) array operating over a > 1 m long wired interface is demonstrated. The head of the system is ∼4.5 cm x 4.5 cm x 4.5 cm making it suitable for hand-held ex vivo applications. This is, to the best of the authors' knowledge, the first example of a SPAD array mounted on the distal end of a handheld FLIM system in this manner. All existing systems to date use a fibre to collect and relay fluorescent light to detectors at the proximal end of the system. This has clear potential biological and biomedical applications. To demonstrate this, the system is used to provide contrast between regions of differing tissue composition in ovine kidney samples, and between healthy and stressed or damaged plant leaves. Additionally, FLIM videos are provided showing that frame rates of > 1 Hz are achievable. It is thus an important step in realising an in vivo miniaturized chip-on-tip FLIM endoscopy system.

Two- Versus 8-Zone Lung Ultrasound in Heart Failure: Analysis of a Large Data Set Using a Deep Learning Algorithm.

Scanning protocols for lung ultrasound often include 8 or more lung zones, which may limit real-world clinical use. We sought to compare a 2-zone, anterior-superior thoracic ultrasound protocol for B-line artifact detection with an 8-zone approach in patients with known or suspected heart failure using a deep learning (DL) algorithm. Adult patients with suspected heart failure and B-lines on initial lung ultrasound were enrolled in a prospective observational study. Subjects received daily ultrasounds with a hand-held ultrasound system using an 8-zone protocol (right and left anterior/lateral and superior/inferior). A previously published deep learning algorithm that rates severity of B-lines on a 0-4 scale was adapted for use on hand-held ultrasound full video loops. Average severities for 8 and 2 zones were calculated utilizing DL ratings. Bland-Altman plot analyses were used to assess agreement and identify bias between 2- and 8-zone scores for both primary (all patients, 5728 videos, 205 subjects) and subgroup (confirmed diagnosis of heart failure or pulmonary edema, 4464 videos, 147 subjects) analyses. Bland-Altman plot analyses revealed excellent agreement for both primary and subgroup analyses. The absolute difference on the 4-point scale between 8- and 2-zone average scores was not significant for the primary dataset (0.03; 95% CI -0.01 to 0.07) or the subgroup (0.01; 95% CI -0.04 to 0.06). Utilization of a 2-zone, anterior-superior thoracic ultrasound protocol provided similar severity information to an 8-zone approach for a dataset of subjects with known or suspected heart failure.

Electronic Nose Development and Preliminary Human Breath Testing for Rapid, Non-Invasive COVID-19 Detection.

We adapted an existing, spaceflight-proven, robust "electronic nose" (E-Nose) that uses an array of electrical resistivity-based nanosensors mimicking aspects of mammalian olfaction to conduct on-site, rapid screening for COVID-19 infection by measuring the pattern of sensor responses to volatile organic compounds (VOCs) in exhaled human breath. We built and tested multiple copies of a hand-held prototype E-Nose sensor system, composed of 64 chemically sensitive nanomaterial sensing elements tailored to COVID-19 VOC detection; data acquisition electronics; a smart tablet with software (App) for sensor control, data acquisition and display; and a sampling fixture to capture exhaled breath samples and deliver them to the sensor array inside the E-Nose. The sensing elements detect the combination of VOCs typical in breath at parts-per-billion (ppb) levels, with repeatability of 0.02% and reproducibility of 1.2%; the measurement electronics in the E-Nose provide measurement accuracy and signal-to-noise ratios comparable to benchtop instrumentation. Preliminary clinical testing at Stanford Medicine with 63 participants, their COVID-19-positive or COVID-19-negative status determined by concomitant RT-PCR, discriminated between these two categories of human breath with a 79% correct identification rate using "leave-one-out" training-and-analysis methods. Analyzing the E-Nose response in conjunction with body temperature and other non-invasive symptom screening using advanced machine learning methods, with a much larger database of responses from a wider swath of the population, is expected to provide more accurate on-the-spot answers. Additional clinical testing, design refinement, and a mass manufacturing approach are the main steps toward deploying this technology to rapidly screen for active infection in clinics and hospitals, public and commercial venues, or at home.

ATM Vehicle Location Privacy and Security Using End -To - End Quantum Key Crypto System

Internet-of-things (IoT) is the latest revolution in electronic industry after internet. Smart appliances, portable computing devices, mobile phones and handheld system dominates in IoT, because a large portion of world population use it. Major applications, mainly financial, e-commerce, information security and sensitive data-communication need special attention in terms of security. Device authentication, encryption, and key distribution are of vital importance to any Internet-of-Things (IoT) systems, such as the new smart city infrastructures. This is due to the concern that attackers could easily exploitthe lack of strong security in IoT devices to gain unauthorized access to the system or to hijack IoT devices to perform denial-of-service attacks on other networks. This creates a strong requirement for providing security solutions into these devices. Key Word: IOT; Communication; Data; Application; Server.

Robotic-assisted unicompartimental knee arthroplasty performed with Navio system: a systematic review.

Robotic-assisted arthroplasty is a relatively modern concept, quickly arising in its use. The aim of this systematic review is to assess, according to the existing literature, which are the functional and clinical outcomes and component positioning and implant survivorship of unicompartmental knee arthroplasty surgery performed using an image-free hand-held robotic system. Moreover, we analyzed whether there are significant differences and advantages compared to conventional surgery. A systematic review has been performed on studies published between 2004 and 2021, on the electronic library databases, according to the Preferred Reporting Items of Systematic Reviews and Meta-analysis (PRISMA) statement. The inclusion criteria were all studies described as unicompartmental knee arthroplasty performed with the Navio robotic system. Fifteen studies were included, and 1,262 unicondylar knee arthroplasties were analyzed. These studies showed a satisfactory recovery of joint function, with a good range of motion (extension <5° and flexion which ranged from 105° to 130.3°) in patients of the NAVIO group. The revision rate was <2% while the infection rate <1%; no postoperative transfusion was needed in all UKA implanted. The use of a robotic tool for unicompartmental knee arthroplasty (UKA) could lead to a better implant positioning and joint alignment than conventional surgery. There is still limited evidence to support that the use of this robot in unicompartmental knee arthroplasty is a greater survivorship than other systems or conventional techniques; therefore, a long-term follow-up is needed.

Agreement and reliability of lower limb muscle architecture measurements using a portable ultrasound device

Although ultrasonography is commonly used to assess muscle architecture, high-end ultrasonography devices lack in portability and are expensive. Recently, ultrasonography devices consisting solely of a probe, an app, and/or a mobile display were introduced. These devices have lower acquisition costs than high-end devices and demonstrate higher portability. Portable systems would allow for cost-effective, on-site athlete or patient screenings of muscle architecture as well as diagnosis of pathologies or injury. Furthermore, portable systems can be easily transported to allow for uncomplicated assessment of athletes belonging to different teams or patients in different hospital units. Nonetheless, the reliability of portable systems and the comparability to high-end devices for muscle architecture assessment have not been investigated.&#x0D; We investigated the agreement and reliability of a portable and handheld ultrasonography system for muscle architecture measurements in human lower limb muscles. We acquired images of the rectus femoris (RF), vastus lateralis (VL) and gastrocnemius medialis (GM) in 36 active healthy participants (15 female, 21 male) at 50% of muscle length using the handheld Lumify (L12-4, linear array 37 mm, Philips Healthcare, Amsterdam, Netherlands) and a high-end laboratory device (ACUSON Juniper, linear-array 54 mm, 12L3, SIEMENS Healthineers, Erlangen, Germany). Muscle length was determined as distance between the proximal and distal muscle tendon junction. We compared measurements of muscle fascicle length, pennation angle and thickness. To assess inter-session reliability of the Lumify system, participants were measured twice within 1 week.&#x0D; Comparing RF architecture measurements of both devices resulted in intra-class correlations (ICCs) ranging from 0.46–0.82 and standardized mean difference (SMDs) ranging from −0.45–0.05. For VL, ICCs ranged from 0.60–0.89 and SMDs ranged from −0.11–0.13. ICCs and SMDs for the GM ranged from 0.82–0.86 and −0.07–0.07. Calculating inter-session reliability for RF resulted in ICCs ranging from 0.44–0.76 and SMDs ranging from −0.38–0.15. For VL, ICCs and SMDs ranged from 0.57–0.75 and −0.13–0.02. ICCs for GM ranged from 0.75–0.92 and SMDs ranged from −0.15–0.16. The highest agreement (ICC ≥ 0.82) and reliability (ICC ≥ 0.75) across all muscles was demonstrated for the measurement of muscle thickness.&#x0D; The Lumify system was comparable to a high-end device and reliable for GM measurements. Nevertheless, agreement and reliability were lower for the RF and VL. Thus, when interpreting longitudinal observed changes in muscle architecture assessed with the Lumify system, measurement errors should be considered. Future investigations should consider including different participant populations, comparing the reliability of different portable systems for muscle architecture assessment as well as including different muscle groups.

The role of hemodialysis access duplex ultrasound for evaluation of patency and access surveillance.

The rise in prevalence of end stage renal disease (ESRD) and the impact on health care resulted in increasing focus on delivery of vascular access. Hemodialysis vascular access is the most common renal replacement therapy method. The vascular access types include arteriovenous fistula, arteriovenous graft, and tunneled central venous catheters. Vascular access function remains an important outcome measure with significant impact on morbidity and health care cost. The survival and quality of life of patients on hemodialysis is dependent on the adequacy of dialysis through proper vascular access. Early detection of failure to mature vascular access, stenosis, thrombosis, and aneurysm or pseudoaneurysm formation remains crucial. Ultrasound can help identify complications, even though ultrasound evaluation of the arteriovenous access is less well defined. Some published vascular access guidelines support ultrasound for detecting stenosis. The evolution of ultrasound has improved throughout the years, both multi parametric top-line systems and hand-held systems. Ultrasound evaluation is inexpensive, rapid, noninvasive, and repeatable, it is a powerful tool used for early diagnosis. The ultrasound image quality still depends on the skill of the operator. Careful attention to technical details is needed and avoidance of several diagnostic pitfalls is necessary. This review is focused on the role of ultrasound for hemodialysis access surveillance, evaluation of maturation, detection of access complications, and aid with cannulation.

Integrating microneedle DNA extraction to hand-held microfluidic colorimetric LAMP chip system for meat adulteration detection

Most microfluidic-based “sample-in-result-out” systems suffer sophisticated microfluidic production processes, high-cost chips, and expensive instruments. They cannot be used in the meat market as well as farmer's markets in rural areas. Here, we developed a hand-held microfluidic chip system for on-site meat species qualitative authentication detection which integrated a simple microneedle DNA extraction and a visual loop-mediated isothermal amplification (LAMP). The chip can be used by easily pricking meat samples, simply hand-shaking the chip, and readily available isothermal heating instead of a complicated DNA extraction process and microfluidic control device. The system demonstrates high specificity and sensitivity for selected six species of meat samples and low to 1% simulated adulteration could be detected within 60 min. Besides, the whole cost was less than 1 dollar. The integrated hand-held microfluidic detection system offers a simple, fast, low-cost “sample-in-result-out” point-of-care device which could be extended to medical diagnosis and animal/plant disease identification.