Set Of Tubes Research Articles

IMPACT OF AIR TRANSPORT ON BLOOD SAMPLE QUALITY.

The aim of this study was to establish the impact of air transport on blood samples packaged with and without cooling elements and effect of outdoor temperature on sample quality. Venous samples from 38 blood donors in winter and 36 in summer were tested for hemolysis and complete blood count. One tube per subject was kept in controlled conditions at +4 °C. Two sets of tubes were sent by plane from Zagreb to Brussels, one with and one without cooling elements, and another two sets were sent to London following the same principle. Packages with cooling elements were stored in controlled warehousing conditions at airports (+2 °C to +8 °C), whereas packages without cooling elements were stored in ambient warehouse conditions. Data loggers were used for temperature monitoring. Our research revealed statistically significant differences in several hematologic parameters when comparing the samples stored in controlled laboratory conditions and those transported by plane. These differences were more pronounced in the samples transported during the summer. Transport conditions without cooling elements had additional negative impact on the sample quality. Transport of samples using cooling elements and controlled warehousing conditions at airports are sometimes not sufficient to maintain laboratory storage conditions.

Experimental investigation of a capillary tube for 2 TR water chiller with R22 & R407C refrigerant

Capillary tube is most widely used expansion device in the refrigeration system having small applications. It is made up of copper tube having small diameter (0.5–5 mm) & very long length (0.5–5 m). The main aim of this research is to study the effect of different dimensions of capillary tube on COP, R.E. & Power input of water chiller and to find the optimum dimensions of capillary tube for which COP of the system is maximum using experimental results. For this, standard experimental test rig having 2 TR refrigeration capacity was developed in order to perform experimentation on different sets of capillary tubes. The result obtained through this experimentation is used to study the effect of changing dimensions of capillary tube on various performance parameters & to find out the optimum dimensions of capillary tube for 2TR water chiller having R22 & R407C as refrigerants. Also, comparative study between results obtained for R22 & R407C is done. The result obtained through this study is useful to design a capillary tube for 2 TR water chiller (having R22 & R407C as refrigerants) for which performance of chiller is maximum for a given application. As R407C refrigerant is direct substitute for R22, so comparative study will be useful to select and modify the dimensions of capillary tube while replacing the refrigerant with substitute one.

Marty Roberts; The Man Who Brought Sorbent Dialysis to Life.

Marty Roberts; The Man Who Brought Sorbent Dialysis to Life.

Information seeking in western lowland gorillas (Gorilla gorilla gorilla).

Many animals will seek information when they do not know the answer to a problem, suggesting that they monitor their knowledge state. In the classic "tubes task," subjects are presented with a set of opaque tubes and either see (visible trials) or do not see (hidden trials) which tube holds a food reward on a given trial. Chimpanzees, bonobos, orangutans, and human children show information-seeking behavior on this task, looking into the tubes to find the reward more on hidden than on visible trials. However, evidence for information-seeking behavior in gorillas is limited. In Experiment 1, gorillas that were presented with a classic information-seeking tubes task showed performance patterns consistent with metacognitive behavior; they looked down tubes more on hidden than on visible trials, their accuracy on hidden trials on which they looked was higher than on hidden trials on which they did not look, and they primarily employed an appropriate search strategy when looking down the tubes. In Experiment 2, we decreased or increased the amount of effort required to look down the tubes by increasing or decreasing the height of the tubes, respectively. Gorillas were less likely to look in tubes on trials that required high effort, but continued to look more on hidden than on visible trials, indicating that their tendency to look was affected by both knowledge state and effort. Together these results provide strong evidence for logical, controlled information-seeking behavior by gorillas.

Clinical Validation of Automated Manufacture of Autologous CD19 CAR-T Cells for Treatment of B Neoplasia

Chimeric antigen receptor (CAR) T cells targeting the CD19 antigen effectively treat adults and children with B-cell hematologic malignancies. Centralized manufacturing may improve performance and accessibility for rapid expansion of this cellular therapy. Here we show the clinical validation of an anti-CD19 CAR (CAR19) comprised of the 4-1BB/CD137 co-stimulatory domain, and TNFRSF19-derived transmembrane region manufactured on the automated CliniMACS Prodigy. The vector and the protocol were provided by Miltenyi Biotec. CART19-HIAE cells were manufactured under current good manufacturing practices (cGMP) at Cellular Therapy Center in Hospital Albert Einstein, São Paulo, Brazil. Clinical apheresis pawn products were obtained from healthy donor undergoing stem transplantation at Hospital Albert Einstein, Sao Paulo, Brazil. Mononuclear peripheral blood cell from apheresis pawn products were processed within 24 h of receipt without cryopreservation. The study was approved by the institutional review board and all healthy donors gave written informed consent. The T cell composition at D0 was 22.14% ± 6.14% CD4 T cells and 23.55% ± 12.2% CD8 T cells. Each sample was loaded onto the CliniMACS Prodigy, and column purified using the TS520 Tubing set and CliniMACS CD4 and CD8 reagents (microbeads). After column purification, CD4 and CD8 T cells were enriched to 57.41% ± 0.05 and 20.55% ± 0.02, respectively. The CliniMACS Prodigy was loaded with 1x108 CD3+ cells and the cells expanded with anti-CD3/CD28 co-stimulation and IL-7/IL-15 supplementation. After culture, we achieved an average 2.09 ± 0.69-fold expansion of CD3C cells (range 32.48% - 99.6%). To examine the transduction efficiency of manufactured CART products, flow cytometry was performed using a peptide that binds the CD19 CAR. The median transduction efficiency of CD3+ cells was 37.31 ± 3.68%, resulting in 1.36x109 ± 0.26x109 anti-19 CAR-T cells. Median transduction of CD4 CAR-T cells was 50.92% ± 4.54% compared to 45.35% ± 5.7% for CD8 CAR-T cells. Transduction efficiency and cell numbers were assessed on days 0, 6, and 12, and expression of CD3, CD4, CD8, and the CD19 CAR was performed by by flow cytometry. Non-T cells fraction after CD4/CD8 enrichment was below 30% (average 25.43% ± 2.89%) e drops below 16% in the final product (average 15.54% ± 7.75%), with the majority of NKT cells (average: 14.83% ± 3.19%) and some NK cells (average: 0.71% ± 0.38%). The multiplicity of infection of samples was approximately 20, leading to an average estimated vector copy number below 5 per CAR-T cell. Cells were harvested from the Prodigy® on day 12. The final product was submitted to quality control analysis including VSVG, GAG, flow cytometry, microbiological tests, endotoxin, karyotype, and mycoplasma. Samples were then diluted accordingly to the specified cohort and were cryopreserved stability control. Therefore, the data show results from three robust validations. The present study (CARTHIAE-1) was the first Phase I study with CAR-T cells approved by the National Health Surveillance Agency (ANVISA - Agência Nacional de Vigilância Sanitária) to treat patients from SUS (Unified Health System) and is scheduled to start in 2022.

A novel anthropomorphic breathing phantom with a pneumatic MR-safe actuator for tissue deformation studies during MRI and radiotherapy

A novel MR-safe anthropomorphic torso phantom with an MR-conditional pneumatic respiration system and inflatable lungs for tissue deformation studies is proposed. The phantom consists of a pair of lungs made from sponges encased in flexible polyurethane. The lung phantom also contains a set of silicone tubes of various diameters to mimic the larger vasculature and airways of the lungs. The lungs are surrounded by a plastic ribcage and immersed in a gelatine hydrogel within a flexible polyurethane skin. A plastic pneumatic pump system was constructed to inflate and deflate the lungs. A fibre optic rotary encoder was constructed to determine the volume of displaced air in the lungs. The pneumatic pump and rotary encoder were constructed of plastic materials to allow placement within the bore of the MR scanner with minimal interaction with the magnetic field. Breath-gated scans and rapid imaging scans (2.5 s per image) were taken of the phantom in the stationary state and during inflation/deflation, and with Cartesian and BLADE k-space sampling. It was found that BLADE shows the least motion artifacts during breathing. This phantom and respiration system shows potential for quality assurance of MRI incorporating breathing corrections and for radiotherapy applications in tracking a moving target.

Survival and Growth of Olive Tree (Olea africana) Seedlings Under Open Field Conditions is Enhanced in Hydrogel Amended Soils Media, Teso Subcounty, Kenya

The rapid decline of timber from natural forests against increasing domestic demand for wood products has caused a steady increase in timber prices in Kenya. Recently, research and development institutions have recognized the ecological and economic value of indigenous tree species and therefore have emphasized the importance of their future production on private smallholder farms rather than in large plantations. This situation has been worsened by climate changes such as the frequent high intensity of prolonged droughts and the nature of soils with poor water retention capacity. As a result, unplanted forest regeneration sites have increased hence a need for re-afforestation of these sites to meet the target for the plantation industry. Therefore, there is a need for mass production of Olea africana seedlings for reforestation programs. One such approach is the application of hydrogels or synthetic polymer organic combinations capable of improving the water and nutrient retention of the soil that can support seedling growth. This study sought to investigate the effects of hydrogel application on selected growth characteristics of O. africana. Seeds were germinated and transferred into two sets of tubes of the same size arranged in a complete randomized block design (CRBD) experiment. The sets were subjected to different levels of hydrogel concentration. Under (0gm as control) and 7gm, 14gm, and 21gm) concentration levels of hydrogel mixed with soil in open field conditions. The height and shoot collar diameter of germinated seedlings were measured every two weeks for two months. The survival of O. africana seedlings decreased with time for all treatments irrespective of the addition of hydrogels with the highest (85%) survival of seedlings on soils mixed with 21gm of hydrogel compared to 0gm hydrogel that recorded (15% survival) eight weeks after transplanting. Application of different levels of hydrogel on soils had a significant influence on the survival of transplanted O. africana seedlings (p˂0.05). Generally, the height of O. africana seedlings increased with time for all types of treatments (0, 7, 14 and 21gm of hydrogel); however, the rate of growth of seedlings was highest (0.667cm /week) on soils treated with 21gm of hydrogel and least (0.33cm/week) on 0gm hydrogel. The shoot collar diameter of O. africana seedlings increased with time for all types of treatments (0, 7, 14 and 21gm of hydrogel); however, the average shoot collar diameter of O. africana seedlings was highest (0.088mm/week) on soils inoculated with 21gm hydrogel and least (0.066mm/week) on soils not inoculated with hydrogel. These results imply that a higher dose of hydrogel significantly enhances the survival and growth characteristics (height and shoot collar diameter) of transplanted seedlings by improving the water-holding capacity of soil and making it available for plant uptake during dry conditions. Hydrogels can therefore be used to amend soils for a sustainable mass regeneration of tropical timber species for reforestation programs, increased forest cover and restoration of biodiversity in Kenya

New design approach for compact evacuated tube collector/storage units

The conventional collector design procedures require extensive time and computational cost. This paper presents a systematic methodology for designing novel evacuated tube collector/storage systems (ETCS). This paper presents a novel methodology that integrates the system decomposition concept with different numerical modeling techniques to optimize the ETCS performance with minimum computational requirements. The presented methodology includes using a single evacuated tube filled with phase change material as the system building block (SBB) of the ETCS system. The enthalpy-porosity and effective heat capacity (EHC) computational fluid dynamics (CFD) methods are used to model the SBB of the novel ETCS based on the required level of details. The CFD models are used to investigate the effect of design configurations and the type of PCM on the thermal performance of the SBB. Moreover, a simplified model for the SBB is developed and used to design an efficient collector/storage unit. The results showed that the EHC model saved the computational time from 2350 min to 6 min compared to the conventional enthalpy-porosity technique with an error of <5 %. Moreover, the use of Rubitherm SP58 increased the energy storage capacity (ESC) of the SBB to 505 kJ compared 417 kJ,375 kJ, and 293 kJ for PCMs Alex 600, paraffin 54, and C22, respectively. The simplified model is used to generate a new design for the ETCS based on the optimum SBB design that uses SP58 with a glass diameter of 58 mm and length 1800 mm. The final ETCS design obtained from the design algorithm consists of four parallel sets of tubes with five tubes in each set. The paper showed the capability of the proposed methodology to design an effective and practical ETCS using minimum computational time and cost.

Извлечение алмазов с аномальной кинетикой люминесценции: результаты экспериментальных исследований

The paper presents the results of experimental studies to recover diamonds with anomalous luminescence kinetics from deposits in Western Yakutia. The characteristics of diamond luminescence are analyzed and a new algorithm for detecting Type IIa diamonds is implemented. Calculations were carried out to select the optimum X-ray tube settings for fluorescence excitation. The results of upgrading the existing equipment and introducing newly manufactured X-ray luminescence separators by equipping them with an optional upgrade kit at ALROSA's concentration facilities are presented. Upgrading with minimal capital investment, i.e. software modification, made it possible to promptly implement recovery of the high-value anomalous diamonds. Pilot technological workflows for extraction of Type IIa diamonds showed presence of these diamonds in the deposits developed by the Aikhal, Nyurba, Udachny and Lomonosov mining and processing plants. The Udachny site was found to have particularly valuable diamond specimens. Monitoring of recovery of Type IIa diamonds greater than 5 mm in size has shown that the increase in marketable products is estimated at about USD 5 million annually.

Correlation between X-ray tube current exposure time and X-ray photon number in GATE.

X-ray image quality relies heavily on the emitted X-ray photon number which depends on X-ray tube current and exposure time. To accurately estimate the absorbed dose in an imaging protocol, it is better to simulate the X-ray imaging with a Monte Carlo platform such as GATE (Geant4 Application for Tomographic Emission). Although input of GATE is the X-ray photon number of the simulated X-ray tube, it lacks a good way to setup the photon number for a desired X-ray tube current setting. To provide a method to correlate the experimental X-ray tube current exposure time and the X-ray photon number in GATE. The accumulated radiation dose of a micro-computed tomography (CT) X-ray tube was recorded at different current exposure times with a general-purpose ion chamber. GATE was used to model the experimental microCT imaging system and calculate the total absorbed dose (cGy) in the sensitive volume of the ion chamber with different X-ray photon numbers. Linear regression models are used to establish a correlation between the estimated X-ray photon number and the X-ray tube settings. At first, one model establishes the relationship between the experimentally measured dose and the X-ray tube setting. Then, another model establishes a relationship between the simulated dose and the X-ray number in GATE. At last, by correlating these two models, a regression model to estimate the X-ray output number from an experimental X-ray tube setting (mAs) is obtained. For a typical micro-CT scan, the X-ray tube is operated at 50 kVp and 0.5 mA for a 500 ms exposure time per projection (0.25 mAs). For these X-ray imaging parameters, the X-ray number per projection is estimated to be 3.613×106 with 1.0 mm Al filter. The findings of this work provide an approach to correlate the experimental X-ray tube current exposure time to the X-ray photon number in the GATE simulation of the X-ray tube to more accurately determine radiation dose for an imaging protocol.

Fate of fentanyl after formalin-fixed tissues: About an authentic case and a stability study

Death leads to various body modifications: lividities, rigidities, cyanosis, swelling, etc. In order to delay the degradation of a body and to keep it in a state close to living, formalin-fixed can be done, in order to stop invasive bacterial growth and slow down decomposition. Formalin is the main preservative liquid used. Formalin will modify the characteristics of the xenobiotics present in the organism: modification of the pH, dilution of the compounds and/or chemical transformations. Thus, the toxicological results after formalin-fixed are therefore not characteristic of the time of death. The difficulty lies in the interpretation of the results. The authors report the case of a 41-year-old man, found unconscious at his home. Resuscitation manoeuvers were unsuccessful and death was pronounced shortly after. An external examination of the body was carried out, revealing no lesion suggestive of violence or cause of death. Femoral blood was collected in a dry tube (blood 1). An autopsy, performed a few days later, also failed to identify a cause of death. In the interval between the external examination and the autopsy, body preservation treatments were carried out. After a deeper investigation of the circumstances, fentanyl transdermal patches (Durogesic®) were discovered at the home of the victim. It was envisaged that the victim died from an overdose of fentanyl, linked of transdermal patches misuse. A complete toxicological analysis was requested on the samples collected during the autopsy, including femoral blood (blood 2). A standard analysis of blood 2 was performed, using validated laboratory procedures. In addition, stability study of fentanyl was conducted in the presence of formalin to determine possible influence. A 30 mL pool of blank blood containing 1 mg/L of fentanyl was prepared and then aliquoted into 30 tubes of 1 mL. Except for the first tube, 20 μL of formalin (20%) was added to each tube. On day 1, the first set of tubes (without formalin) was extracted and analyzed on UPLC-MS/MS. The stability study was spread over 4 months, and each analysis was done in duplicate ( n = 2). The femoral blood 2 analyzes showed the presence of methanol (present in the preservative liquid), fentanyl at toxic concentration (30 ng/mL) and norfentanyl (4 ng/mL). No other compound was detected. It is possible that the concentrations measured in blood 2 were lower than those at the time of death, due to preservative treatment, without being able to evaluate the percentage of degradation or dilution. However, the stability study of fentanyl over 4 months did not show any fentanyl degradation in the presence of formalin, as the concentration remained stable throughout the study. The blood 1 collected during the external examination was also analyzed. Fentanyl and norfentanyl were measured at 16 ng/mL and 1 ng/mL, respectively. The differences in concentrations between the two femoral blood samples confirm that there is no degradation of fentanyl in presence of formalin. Moreover, the higher concentrations measured after preservative treatments are in favor of a redistribution of fentanyl from the skin where the patches were worn (relocation of fentanyl linked to preservation treatments operations). The results can also be explain by the breaking of the plasma protein binding of fentanyl to albumin (estimated at 80–85%) in presence of formalin, and thus a significant increase in the concentration of free-fentanyl. A stability study showed that fentanyl does not degrade in the presence of formalin. Nevertheless, other formalin-related phenomena can have an impact on the concentrations (transfer of molecules and breaking of protein bonds), making interpretation very difficult, if not impossible.

Experimental investigations on the acoustical performance of open-celled metal foams under grazing flow

Open-celled metal foams offer a possible solution for implementing acoustic liners in non-traditional nacelle locations, such as directly over the turbofan rotor. Previously, we have shown that the normal incidence absorption performance of metal foams can be further improved by compressing them to reduce their effective pore size. In this paper, we focus on the acoustical performance of compressed metal foams under grazing flow conditions. Experimental tests were conducted using a grazing flow impedance tube set up within Spirit AeroSystems' acoustics lab. Metal foams with four different compression ratios were tested under various flow rates and incident sound pressure levels. The sound pressure measurements were then utilized to educe their effective impedance under grazing flow conditions. Our results show that a uniform through-thickness compression can improve the acoustic performance of open-celled metal foams under grazing flow conditions and can aid the further development of acoustic liners for over the rotor applications.

Study of the flat plate solar collector's efficiency for sustainable and renewable energy management in a building by a phase change material: Containing paraffin-wax/Graphene and Paraffin-wax/graphene oxide carbon-based fluids

Energy management in a building is to control and lessen the energy consumption, to decrease both costs and carbon emissions. Building-integrated thermal systems are adept to produce heat. Various scenarios have been planned to integrate heat into a building formation to enhance performance of entity system, supply indoor heating, and provide hot water. Concept backside Flat-plate Solar collector is that Sun warmth the set of tubes. This surface collects as much energy as preferable, and then water heats by this energy. This study aims to compare the Energy efficiency between phase change materials (PCMs) containing Paraffin-wax/Graphene and Paraffin-wax/Graphene Oxide carbon-based nanofluids for renewable, clean, green and sustainable energy systems such as Flat Plate Solar Collectors by applying these PCMs in Buildings heating systems. Results showed that, Thermal conductivity of both Graphene/P-wax and Graphene Oxide/P-wax was enhanced in comparison with Paraffin. Also, trend of Graphene showed better thermal performance.

The Scientific Importance of Returning Airfall Dust as a Part of Mars Sample Return (MSR).

Dust transported in the martian atmosphere is of intrinsic scientific interest and has relevance for the planning of human missions in the future. The MSR Campaign, as currently designed, presents an important opportunity to return serendipitous, airfall dust. The tubes containing samples collected by the Perseverance rover would be placed in cache depots on the martian surface perhaps as early as 2023-24 for recovery by a subsequent mission no earlier than 2028-29, and possibly as late as 2030-31. Thus, the sample tube surfaces could passively collect dust for multiple years. This dust is deemed to be exceptionally valuable as it would inform our knowledge and understanding of Mars' global mineralogy, surface processes, surface-atmosphere interactions, and atmospheric circulation. Preliminary calculations suggest that the total mass of such dust on a full set of tubes could be as much as 100 mg and, therefore, sufficient for many types of laboratory analyses. Two planning steps would optimize our ability to take advantage of this opportunity: (1) the dust-covered sample tubes should be loaded into the Orbiting Sample container (OS) with minimal cleaning and (2) the capability to recover this dust early in the workflow within an MSR Sample Receiving Facility (SRF) would need to be established. A further opportunity to advance dust/atmospheric science using MSR, depending upon the design of the MSR Campaign elements, may lie with direct sampling and the return of airborne dust. Summary of Findings FINDING D-1: An accumulation of airfall dust would be an unavoidable consequence of leaving M2020 sample tubes cached and exposed on the surface of Mars. Detailed laboratory analyses of this material would yield new knowledge concerning surface-atmosphere interactions that operate on a global scale, as well as provide input to planning for the future robotic and human exploration of Mars. FINDING D-2: The detailed information that is possible from analysis of airfall dust can only be obtained by investigation in Earth laboratories, and thus this is an important corollary aspect of MSR. The same information cannot be obtained from orbit, from in situ analyses, or from analyses of samples drilled from single locations. FINDING D-3: Given that at least some martian dust would be on the exterior surfaces of any sample tubes returned to Earth, the capability to receive and curate dust in an MSR Sample Receiving Facility (SRF) is essential. SUMMARY STATEMENT: The fact that any sample tubes cached on the martian surface would accumulate some quantity of martian airfall dust presents a low-cost scientifically valuable opportunity. Some of this dust would inadvertently be knocked off as part of tube manipulation operations, but any dust possible should be loaded into the OS along with the sample tubes. This dust should be captured in an SRF and made available for detailed scientific analysis.

Quick and Easy Isolation of Immune Cells From Large-Volume Samples

Abstract Large-scale cell isolation is commonly performed in labs and core facilities for cell banking and drug discovery, and as a critical step in cell therapy manufacturing. Current methods can be a significant bottleneck in a lab’s workflow, often requiring a full day for sample processing and cell isolation. To address this need, we have developed two methods: manual column-free isolation using the Easy 250 EasySep™ magnet, and automated cell isolation in a closed system using RoboSep™-C. The Easy 250 magnet allows users to isolate cells from a full leukopak of up to 20 billion cells in under 30 minutes by simply pipetting out their target cells. Negative selection protocols have been optimized to achieve 95.3% T cell, 97.2% CD4+ T cell, 91.9% CD8+ T cell, 99.4% B cell, 96.5% NK cell, and 91.5% monocyte purities. Positive selection protocols obtain 95.4% CD3+ cell, 94.4% CD4+ T cell, 93.9% CD8+ T cell, and 96.2% CD14+ cell purities. RoboSep™-C automates this cell isolation procedure, along with the cell washing steps for sample preparation, in as little as 50 minutes. The instrument features a scale tower, pump and clamp modules to direct fluid through defined paths, and a magnet for separation of labelled cells. The system uses a sterile single-use tubing set that incorporates a cartridge for cell washing and concentration, and a magnet chamber for cell separation. Starting with fresh leukopaks, we obtained 95.9% T cell, 95.8% CD4+ T cell, and 89.6% CD8+ T cell purities following negative selection, and 92.0% CD4+ T cell and 89.5% CD8+ T cell purities following positive selection. These approaches offer efficient and user-friendly cell isolation that allow researchers to scale up their operations, and can be easily integrated upstream of existing workflows.

Adenoidectomy may decrease the need for a third set of tympanostomy tubes in children

ObjectiveTo determine whether removing or retaining adenoids at the time of placement of a second set of ear tubes impacts the need for a third set of ear tubes later in childhood. Study designSingle-institution retrospective case series. SettingTertiary academic university hospital. MethodsWe identified pediatric subjects who had undergone a second ear tube placement between 1/1/17 and 9/1/19. Subjects were stratified into two groups: 1) adenoids removed at time of second tympanostomy tube insertion (TT+A) and 2) adenoids retained at time of second tympanostomy tube insertion (TT-A). A subset of children less than age 4 was also studied independently. The primary outcome was number of patients requiring a third set of tympanostomy tubes. ResultsA total of 136 subjects met inclusion and exclusion criteria. Among children less than 4 years of age (n = 99), the incidence of requiring a third set of tubes was significantly lower in the TT+A group <4 (12.8%; 6/47) compared to the TT-A group <4 (44.2%; 23/52) (p = 0.0008) with an odds ratio of 0.18 (95%CI 0.067–0.51) and number needed to treat of 3.2. ConclusionPerforming adenoidectomy in children less than 4 years of age at the second tympanostomy procedure was associated with a reduced incidence of requiring a third set of ear tubes.

Manufacture and use: bone and tooth objects from the Late Bronze Age ‘shaman's grave’ at Przeczyce, Poland

The microscopic analysis of tool marks on objects from the Late Bronze Age ‘shaman's grave’ at Przeczyce, Poland, has demonstrated that two wild boar tusk pendants, a bone disc and a set of bone tubes were manufactured exclusively using metal tools. We argue that the tubes were a musical instrument that originally consisted of several separate pieces, rather than a pan flute, as has previously been suggested.

Feasibility of Dual-Energy Cone-Beam CT of Bone Marrow Edema Using Dual-Layer Flat Panel Detectors.

We investigated the feasibility of detection and quantification of bone marrow edema (BME) using dual-energy (DE) Cone-Beam CT (CBCT) with a dual-layer flat panel detector (FPD) and three-material decomposition. A realistic CBCT system simulator was applied to study the impact of detector quantization, scatter, and spectral calibration errors on the accuracy of fat-water-bone decompositions of dual-layer projections. The CBCT system featured 975 mm source-axis distance, 1,362 mm source-detector distance and a 430 × 430 mm2 dual-layer FPD (top layer: 0.20 mm CsI:Tl, bottom layer: 0.55 mm CsI:Tl; a 1 mm Cu filter between the layers to improve spectral separation). Tube settings were 120 kV (+2 mm Al, +0.2 mm Cu) and 10 mAs per exposure. The digital phantom consisted of a 160 mm water cylinder with inserts containing mixtures of water (volume fraction ranging 0.18 to 0.46) - fat (0.5 to 0.7) - Ca (0.04 to 0.12); decreasing fractions of fat indicated increasing degrees of BME. A two-stage three-material DE decomposition was applied to DE CBCT projections: first, projection-domain decomposition (PDD) into fat-aluminum basis, followed by CBCT reconstruction of intermediate base images, followed by image-domain change of basis into fat, water and bone. Sensitivity to scatter was evaluated by i) adjusting source collimation (12 to 400 mm width) and ii) subtracting various fractions of the true scatter from the projections at 400 mm collimation. The impact of spectral calibration was studied by shifting the effective beam energy (± 2 keV) when creating the PDD lookup table. We further simulated a realistic BME imaging framework, where the scatter was estimated using a fast Monte Carlo (MC) simulation from a preliminary decomposition of the object; the object was a realistic wrist phantom with an 0.85 mL BME stimulus in the radius. The decomposition is sensitive to scatter: approx. <20 mm collimation width or <10% error of scatter correction in a full field-of-view setting is needed to resolve BME. A mismatch in PDD decomposition calibration of ± 1 keV results in ~25% error in fat fraction estimates. In the wrist phantom study with MC scatter corrections, we were able to achieve ~0.79 mL true positive and ~0.06 mL false positive BME detection (compared to 0.85 mL true BME volume). Detection of BME using DE CBCT with dual-layer FPD is feasible, but requires scatter mitigation, accurate scatter estimation, and robust spectral calibration.

Phantom Validation of a Conservation of Activity-Based Partial Volume Correction Method for Arterial Input Function in Dynamic PET Imaging

Dynamic PET (dPET) imaging can be utilized to perform kinetic modelling of various physiologic processes, which are exploited by the constantly expanding range of targeted radiopharmaceuticals. To date, dPET remains primarily in the research realm due to a number of technical challenges, not least of which is addressing partial volume effects (PVE) in the input function. We propose a series of equations for the correction of PVE in the input function and present the results of a validation study, based on a purpose built phantom. 18F-dPET experiments were performed using the phantom on a set of flow tubes representing large arteries, such as the aorta (1” 2.54 cm ID), down to smaller vessels, such as the iliac arteries and veins (1/4” 0.635 cm ID). When applied to the dPET experimental images, the PVE correction equations were able to successfully correct the image-derived input functions by as much as 59 ± 35% in the presence of background, which resulted in image-derived area under the curve (AUC) values within 8 ± 9% of ground truth AUC. The peak heights were similarly well corrected to within 9 ± 10% of the scaled DCE-CT curves. The same equations were then successfully applied to correct patient input functions in the aorta and internal iliac artery/vein. These straightforward algorithms can be applied to dPET images from any PET-CT scanner to restore the input function back to a more clinically representative value, without the need for high-end Time of Flight systems or Point Spread Function correction algorithms.

Party like a Sumerian: reinterpreting the ‘sceptres’ from the Maikop kurgan

The Bronze Age Maikop kurgan is one of the most richly furnished prehistoric burial mounds in the northern Caucasus. Its excavation in 1897 yielded a set of gold and silver tubes with elaborate tips and decorative bull figurines. Interpretations of these tubes include their use as sceptres and as poles to support a canopy. Re-examination of these objects, however, suggests they were used as tubes for the communal drinking of beer, with integral filters to remove impurities. If correct, these objects represent the earliest material evidence of drinking through long tubes—a practice that became common during feasts in the third and second millennia BC in the ancient Near East.