Small Chamber Research Articles

Emodin regulated lactate metabolism by inhibiting MCT1 to delay non-small cell lung cancer progression.

Lung cancer is one of the most common malignant tumors in the world, with high incidence rate and mortality. Monocarboxylate transporter (MCT) 1 has been found to be widely expressed in various tumors and plays a crucial role in regulating energy metabolism. Emodin, as an important traditional Chinese medicine in China, has been reported to inhibit the progression of lung cancer. However, its potential mechanism has not been fully elucidated. The effects of emodin and MCT1 inhibitor AZD3965 on the proliferation, migration, and invasion of lung cancer cells were detected using cell counting kit-8 (CCK-8) assay, wound-healing assay, and transwell small chamber assay. The content of glucose, lactate, and pyruvate in the cell culture medium was detected using a glucose, lactate, and pyruvate detection kit, and also detected protein expression using western blotting. In addition, to investigate the effects of emodin and AZD3965 on lung cancer in vivo, we constructed nude mice subcutaneous transplant tumor model by subcutaneous injection of lung cancer cells. The results showed that emodin and AZD3965 could inhibit the proliferation, migration, and invasion of lung cancer cells. At the same time, they could inhibit the expression of MCT1 in lung cancer cells and promote the release of lactate, but did not affect the content of glucose and pyruvate. In vivo experiments had shown that emodin and AZD3965 could effectively inhibit the growth of lung cancer and inhibit the expression of MCT1. All in all, our data suggested that emodin inhibited the proliferation, migration, and invasion of lung cancer cells, possibly by inhibiting MCT1, providing important theoretical basis for elucidating the mechanism of emodin in treating lung cancer.

Small Left Ventricular Chamber Size and Mortality in a Large General Population

Enlargement of the left ventricle (LV) is an important marker of adverse cardiac remodeling and poor prognosis. Previous studies demonstrated increased cardiovascular risk in small subsets of patients with small LV chamber size, however, the prognostic implications of small chamber size in a general population remains unclear. The objective of this study was to examine the prognosis of a small LV chamber in a large general cohort. All consecutive subjects that underwent echocardiography examinations from 2011 to 2023 were retrieved for analysis. Small chamber size was defined as end-diastolic diameter less than 42 mm for men and 37.8 mm for women as per ASE guidelines. The primary endpoint for the study was all-cause mortality. 46,529 subjects (mean age 60 ± 19 years, 56% males) were included of whom 3,787 had small LV chamber size. Clinical variables associated with small chamber included increasing age and lower BSA. Echocardiographic variables included higher relative wall thickness, and E/e' ratio. On multivariable analysis, the presence of a small LV was significantly associated with mortality (HR 1.34 with 95% CI 1.22-1.46; p <0.001). This finding was significant in both older (over 65 years) (HR 1.30 95% CI 1.19-1.41; p <0.001) and younger (HR 2.09 95% CI 1.81-2.41; p <0.001) subjects and in both males and females. In conclusion, in this retrospective large cohort study, small LV chamber size was significantly associated with mortality in a broad range of patients. Further study is necessary to elucidate mechanisms and design preventive strategies.

How to Make the Skin Contact Area Controllable by Optical Calibration in Wearable Tactile Displays of Softness.

Virtual reality systems may benefit from wearable (fingertip-mounted) haptic displays capable of rendering the softness of virtual objects. According to neurophysiological evidence, the easiest reliable way to render a virtual softness is to generate purely tactile (as opposed to kinaesthetic) feedback to be delivered via a finger-pulp-interfaced deformable surface. Moreover, it is necessary to control not only the skin indentation depth by applying quasi-static (non-vibratory) contact pressures, but also the skin contact area. This is typically impossible with available devices, even with those that can vary the contact area, because the latter cannot be controlled due to the complexity of sensing it at high resolutions. This causes indetermination on an important tactile cue to render softness. Here, we present a technology that allows the contact area to be open-loop controlled via personalised optical calibrations. We demonstrate the solution on a modified, pneumatic wearable tactile display of softness previously described by us, consisting of a small chamber containing a transparent membrane inflated against the finger pulp. A window on the device allowed for monitoring the skin contact area with a camera from an external unit to generate a calibration curve by processing photos of the skin membrane interface at different pressures. The solution was validated by comparisons with an ink-stain-based method. Moreover, to avoid manual calibrations, a preliminary automated procedure was developed. This calibration strategy may be applied also to other kinds of displays where finger pulps are in contact with transparent deformable structures.

Cornea Endothelial Cell Loss Before and After Explantation of Artisan and Artiflex Iris-Fixated Phakic Intraocular Lenses

PurposeTo investigate the risk factors for corneal endothelial cell density (ECD) loss of two types of iris-fixated phakic intraocular lenses (pIOL) and indicate the cutoff values for preventing irreversible ECD loss after explantation. DesignThe retrospective, comparative, clinical cohort study MethodsTotal 114 eyes of 61 patients were included in this study. Fifty-five eyes with Artisan pIOL and 59 eyes with Artiflex pIOL had undergone explantation of pIOLs due to continuous ECD loss. Correlation analysis was performed to assess the ocular parameters associated with ECD loss. Receiver operating characteristic (ROC) curve was performed to set cutoff values of ocular parameters to prevent ECD loss after explantation. ResultThe mean ECD before explantation was 1637 cells/mm2 in Artisan group and 1769 cells/mm2 in Artiflex group. The distance of cornea endothelium to IOL center and edges were all significantly higher in Artisan group (p <0.05). The risk factor of decreased ECD in Artisan group were small anterior chamber angle (ACA), and distance of nasal edge of IOL to endothelium and iris fixation to nasal limbus distance, and differences of fixation length. In Artiflex group, ACA, distance of nasal edge of IOL to endothelium, both limbus to IOL fixation length, fixation length, iris pigmentation grading were the risk factors. At 1 year after the pIOL removal, the population demonstrating ΔECD >10% were significantly higher in Artisan group than Artiflex group (p <0.05). In ROC curve analysis, the cutoff value of preoperative ECD to prevent significant post-explantation ECD loss was 1683.5 cells/mm2 in Artisan group and 1648 cells/mm2 in Artiflex group. ConclusionThis study examined the existing explantation guidelines for these lenses. In analyzing the longterm prognosis of cornea ECD with Iris-fixated phakic intraocular lens, it is important to identify the relevant anatomical factors. Small ACA, and short distances from IOL to endothelium and from limbus to iris fixation especially in the nasaSSSl region were significant risk factors to continuous ECD loss in both lenses. To minimize irreversible ECD loss after explantation, it is important to determine the optimal period of explantation by observing both ECD and structural changes.

Large eddy simulation of highly underexpanded sonic jets from elliptical nozzles

The injection of high-pressure jets into quiescent air poses significant challenges in fluid dynamics, pertinent to various industrial engineering applications. This study used large eddy simulations on a massively parallel computational framework, employing a grid of over 600 million nodes, to investigate the behavior of highly underexpanded sonic jets from elliptical nozzles at a nozzle pressure ratio of 15. Three elliptical nozzles, with aspect ratios of 1.5, 2.2, and 3.0, each having a sectional area equivalent to that of a circular jet with a diameter of D=1 mm, were analyzed. The aim was to clarify the gasdynamic and mixing characteristics of these jets to guide the design of next-generation injectors. A detailed analysis of the flow provided insights into the mechanisms of turbulence generation and Reynolds stress anisotropy. This was achieved using the componentality contour approach and a modified barycentric color mapping scheme, offering valuable reference data for developing lower-order models. The results indicate a non-axisymmetric radial expansion of the jet boundary in all elliptical injectors, leading to an axis switch phenomenon. The use of elliptical orifices was found to reduce jet penetration, mitigating issues such as fuel impingement in small engine combustion chambers and promoting improved air–fuel mixing quality.

Effects of firefighters’ protective gloves on physiological responses, psychological responses, and manual performance in a cold environment

This study aimed to investigate the effects of firefighters' protective gloves on physiological responses, psychological responses, and manual performance in a cold environment through human trials. Twelve participants wearing firefighter protective equipment were exposed to a 16 °C environment, while their hands were exposed to a small chamber of 0 °C with (FPG) and without (CON) firefighting protective gloves. During the trials, physiological responses (core temperature (Tc), the mean skin temperature (Tsk), and heart rate (HR)), psychological responses (thermal sensation vote (TSV) and pain sensation vote (PSV)), and manual performance (handgrip strength, manual dexterity, maximum finger flexion, and tactile sensitivity)) were obtained. The results indicated a significant difference (p < 0.05) between FPG and CON regarding Tsk. Furthermore, pain sensation occurred when the mean skin temperature of the hand was between 15 °C and 20 °C. Gloves significantly (p < 0.05) reduced handgrip strength, manual dexterity, and tactile sensitivity in the cold exposure. This study provides fundamental knowledge for cold strain assessment and high-performance protective glove development with the potential to improve firefighters’ safety and health.

Soft pneumatic actuators for pushing fingers into extension

BackgroundCompliant pneumatic actuators possess many characteristics that are desirable for wearable robotic systems. These actuators can be lightweight, integrated with clothing, and accommodate uncontrolled degrees of freedom. These attributes are especially desirable for hand exoskeletons, where the soft actuator can conform to the highly variable digit shape. In particular, locating the pneumatic actuator on the palmar side of the digit may have benefits for assisting finger extension and resisting unwanted finger flexion, but this configuration requires suppleness to allow digit flexion while retaining sufficient stiffness to assist extension.MethodsTo meet these needs, we designed an actuator consisting of a hollow chamber long enough to span the joints of each digit while sufficiently narrow not to inhibit finger adduction. We explored the geometrical design parameter space for this chamber in terms of shape, dimensions, and wall thickness. After fabricating an elastomer-based prototype for each actuator design, we measured active extension force and passive resistance to bending for each chamber using a mechanical jig. We also created a finite element model for each chamber to enable estimation of the impact of chamber deformation, caused by joint rotation, on airflow through the chamber. Finally, we created a prototype hand exoskeleton with the chamber parameters yielding the best outcomes.ResultsA rectangular cross-sectional area was preferable to a semi-obround shape for the chamber; wall thickness also impacted performance. Extension joint torque reached 0.33 N-m at a low chamber pressure of 48.3 kPa. The finite element model confirmed that airflow for the rectangular chamber remained high despite deformation resulting from joint rotation. The hand exoskeleton created with the rectangular chambers enabled rapid movement, with a cycle time of 1.1 s for voluntary flexion followed by actuated extension.ConclusionsThe developed soft actuators are feasible for use in promoting finger extension from the palmar side of the hand. This placement utilizes pushing rather than pulling for digit extension, which is more comfortable and safer. The small chamber volumes allow rapid filling and evacuation to facilitate relatively high frequency finger movements.

How conductivity boundaries influence the electric field induced by transcranial magnetic stimulation in in vitro experiments

Although transcranial magnetic stimulation (TMS) has become a valuable method for non-invasive brain stimulation, the cellular basis of TMS activation of neurons is still not fully understood. In vitro preparations have been used to understand the biophysical mechanisms of TMS, but in many cases these studies have encountered substantial difficulties in activating neurons. The hypothesis of this work is that conductivity boundaries can have large effects on the electric field in commonly used in vitro preparations. Our goal was to analyze the resulting difficulties in in vitro TMS using a simulation study, using a charge-based boundary element model. We decomposed the total electric field into the sum of the primary electric field, which only depends on coil geometry and current, and the secondary electric field arising from conductivity boundaries, which strongly depends on tissue and chamber geometry. We investigated the effect of the conductivity boundaries on the electric field strength for a variety of in vitro experimental settings to determine the sources of difficulty. We showed that conductivity boundaries can have large effects on the electric field in in vitro preparations. Depending on the geometry of the air-saline and the saline-tissue interfaces, the secondary electric field can significantly enhance, or attenuate the primary electric field, resulting in a much stronger or weaker total electric field inside the tissue; we showed this using a realistic preparation. Submerged chambers are generally much more efficient than interface chambers since the secondary field due to the thin film of saline covering the tissue in the interface chamber opposes the primary field and significantly reduces the total field in the tissue placed in the interface chamber. The relative dimensions of the chamber and the TMS coil critically determine the total field; the popular setup with a large coil and a small chamber is particularly sub-optimal because the secondary field due to the air-chamber boundary opposes the primary field, thereby attenuating the total field. The form factor (length vs width) of the tissue in the direction of the induced field can be important since a relatively narrow tissue enhances the total field at the saline-tissue boundary. Overall, we found that the total electric field in the tissue is higher in submerged chambers, higher if the chamber size is larger than the coil and if the shorter tissue dimension is in the direction of the electric field. Decomposing the total field into the primary and secondary fields is useful for designing in vitro experiments and interpreting the results.

Small ion pulse ionization chamber for radon measurement in underground space

Radon, prevalent in underground spaces, requires continuous monitoring due to health risks. Traditional detectors are often expensive, bulky, and ill-suited for humid environments in underground spaces. This study presents a compact, cost-effective radon detector designed for long-term, online monitoring. It uses a small ionization chamber with natural airflow, avoiding the need for fans or pumps, and includes noise filtering and humidity mitigation. Featuring multi-point networking and easy integration capabilities, this detector significantly enhances radon monitoring in challenging, underground conditions.

Analysis of deformation and multi-angle tip contact in a combined mechanism of thin-walled membrane forces and inextensible layers in soft actuators

Soft actuators have extensive applications in operations, are generally made of elastomers, and generate large deformation. It makes accurately predicting their deformation behavior challenging. This study considers the combined effects of chamber sidewall expansion and inextensible layer strain mechanisms on the actuator's bending and tip contact force. We separately model the expansion of the chamber sidewall and the strain in the inextensible layer using the expanding membrane and strain beam theory. The theoretical model presented to predict the contact area of the sidewall expanding membrane under multiple bending conditions. The analytical models for three actuator states are established: 1) Free space; 2) Tip contact at multiple angles; and 3) Grasping state. The proposed theoretical model accurately predicts deformation, force characteristics, and the requisite pressure for object grasping, and its applicability extends to similar soft actuators. Comparative analyses with finite element methods (FEM) and experimental results validate the model's computational efficiency, reduced design variables, and accurate prediction of diverse deformations and tip contact forces. Notably, the model outperforms with shorter computation times. The large and small chamber spacing errors are approximately 10 % and 5 %, respectively.

NAD+ precursors prolong survival and improve cardiac phenotypes in a mouse model of Friedreich's Ataxia.

Friedreich's ataxia (FRDA) is a progressive disorder caused by insufficient expression of frataxin, which plays a critical role in assembly of iron-sulfur centers in mitochondria. Individuals are cognitively normal but display a loss of motor coordination and cardiac abnormalities. Many ultimately develop heart failure. Administration of nicotinamide adenine dinucleotide-positive (NAD+) precursors has shown promise in human mitochondrial myopathy and rodent models of heart failure, including mice lacking frataxin in cardiomyocytes. We studied mice with systemic knockdown of frataxin (shFxn), which display motor deficits and early mortality with cardiac hypertrophy. Hearts in these mice do not "fail" per se but become hyperdynamic with small chamber sizes. Data from an ongoing natural history study indicate that hyperdynamic hearts are observed in young individuals with FRDA, suggesting that the mouse model could reflect early pathology. Administering nicotinamide mononucleotide or riboside to shFxn mice increases survival, modestly improves cardiac hypertrophy, and limits increases in ejection fraction. Mechanistically, most of the transcriptional and metabolic changes induced by frataxin knockdown are insensitive to NAD+ precursor administration, but glutathione levels are increased, suggesting improved antioxidant capacity. Overall, our findings indicate that NAD+ precursors are modestly cardioprotective in this model of FRDA and warrant further investigation.

Sound absorption uncertainty in small reverberation chambers

Manufacturers in the mobility industry typically measure and specify the sound absorption coefficient of materials using a small reverberation chamber according to SAE J2883. These chambers have a 6 to 25 cubic meter volume, use a 1.0 meter x 1.2 meter sample size and report sound absorption in the one-third octave bands from about 400 Hz to 10,000 Hz. This is in contrast to a full-size chamber built to satisfy the requirements of ASTM C423 or ISO 354, which have about a 200 cubic meter volume, use a 2.4 x 2.7 or 3.2 x 3.2 square meter sample size and report sound absorption in one-third octave bands from 100 to 5,000 Hz. Although the room and sample size dimensions scale, many of the factors that contribute to uncertainty in the measurement do not scale. These include relative humidity, temperature, and other physical measurements and if the same instrumentation is used, microphone calibration and measurement uncertainty in the higher frequency range. This paper examines the potential measurement uncertainty in these chambers over the 400 to 10,000 Hz frequency range and compares this to past uncertainty analyses of full-size chambers over a similar frequency range.

Distribution of brood of the acorn ant Temnothorax crassispinus in artificial nests after forced migration

Nest sites are important for social insects, as they provide refuge against enemies and ensure optimal conditions for the brood development. In large nests, the different chambers can be used for different reasons; for example, for food storage or as a brood chamber. Acorn ants from the genus Temnothorax dwell in small cavities in acorns and wood; however, even such small chambers can have a high degree of spatial heterogeneity. During this study, the distribution of brood items of the acorn ant Temnothorax crassispinus inside artificial nest cavities composed of three chambers in a linear system was analysed. 29 ant colonies were photographed 13 times during a period of approximately one month: during three consecutive days, and after forced migrations. I found that the distribution of the brood inside the nest cavity was similar during the consecutive days; however, after the forced migration, the distribution typically changed. Almost all the brood items were kept farther from the entrance. Keeping the brood farther from the entrance could be explained as a safer option.

Association of body adiposity with left ventricular concentric remodeling and diastolic dysfunction

AbstractBackgroundObesity is a significant risk factor for heart failure with preserved ejection fraction (HFpEF). In this study, we explore the relationships between body mass index (BMI) and adipose tissue compartments such as visceral adipose tissue (VAT), subcutaneous adipose tissue (SAT), and epicardial adipose tissue (EAT), with respect to left ventricular (LV) structure and function in subjects with preserved LV systolic function.MethodsBetween January and December 2020, this retrospective study included 749 participants who exhibited preserved LV systolic function and underwent transthoracic echocardiography along with abdominal computed tomography. LV structural and functional variables as well as EAT, VAT, and SAT thickness were evaluated using echocardiography and computed tomography.ResultsSAT decreased, while VAT and EAT progressively increased with age. There were significant correlations between BMI and various adipose tissues, with the strongest correlation observed with SAT (r = .491, p &lt; .001) compared to VAT (r = .371, p &lt; .001) or EAT (r = .135, p &lt; .001). However, EAT demonstrated the most substantial association with decreased LV end‐diastolic dimension, LV end‐systolic dimension, and septal mitral annular velocity and increased relative wall thickness (all p &lt; .05), while VAT and SAT did not show significant associations with LV remodeling and functional parameters after adjusting for clinical variables.ConclusionEAT is the most critical adipose tissue influencing LV geometric and functional changes, compared with VAT or SAT. Thick EAT is associated small LV chamber size, concentric remodeling, and relaxation abnormalities.

Pseudogomphonema lukinicum sp. nov. (Bacillariophyceae), a new endophytic diatom found inside multicellular red algae from the Northwest Pacific

Abstract In our collections from the Northwest Pacific waters, we found several specimens of the red algae Lukinia dissecta and Callophyllis perestenkoae with darker spots on their thalli, which contained an unusual pennate diatom. A detailed morphological analysis based on light and scanning electron microscopy observations made it possible to describe a new species of endophytic diatom, Pseudogomphonema lukinicum sp. nov. Stonik et Skriptsova. The new species has some morphological features typical of the genus, such as the heteropolarity of the valves, the presence of pseudosepta and small apical chambers at both poles of the valves, and nonporous girdle bands. Pseudogomphonema lukinicum has been described and distinguished from the other species in the genus on the basis of a combination of morphological traits, including relatively small cell dimensions, a slightly asymmetrical valve to the transapical axis, with obtusely rounded headpole and narrower footpole, the large asymmetrical central area, and the presence of apical chambers at both poles. Pseudogomphonema lukinicum is the second representative of Pseudogomphonema known to be living endophytically. The data on the species composition of endophytic diatoms in marine macroalgae, their habitats, and host organisms reported in the literature to date are summarized.

Effect of the Twist Crystallinity of N‐Polar AlN Underlayer on the Electrical Properties of GaN/AlN Structures

Recently, N‐polar GaN/AlGaN/AlN high‐electron‐mobility transistors (HEMTs) have been demonstrated using molecular beam epitaxy (MBE). However, the MBE method is not suitable for mass production because of the need for ultrahigh vacuum, small chamber size, and long deposition time. This study fabricates N‐polar GaN‐ or AlGaN‐channel HEMTs on AlN with polarization directions opposite to those of Ga‐polar GaN‐based HEMTs without any cap layer and demonstrates field‐effect transistor static characteristics. In this article, the focus is on the crystal quality of the underlying layer and the effect of crystalline quality on electrical properties is investigated. The crystalline quality of the twist component of the N‐polar AlN layer is improved by combining the Al‐polar tiny‐pit layer and polarity inversion from Al‐ to N‐polar. Finally, it is shown that the crystalline quality of the twist component is a crucial factor for improving the electron mobility of the N‐polar GaN channel and simultaneously increasing IDS.

Proliferation of SH-SY5Y neuroblastoma cells on confined spaces

Background:Microfluidics offers precise drug delivery and continuous monitoring of cell functions, which is crucial for studying the effects of toxins and drugs. Ensuring proper cell growth in these space-constrained systems is essential for obtaining consistent results comparable to standard Petri dishes. New method:We investigated the proliferation of SH-SY5Y cells on circular polycarbonate chambers with varying surface areas. SH-SY5Y cells were chosen for their relevance in neurodegenerative disease research. Results:Our study demonstrates a correlation between the chamber surface area and SH-SY5Y cell growth rates. Cells cultured in chambers larger than 10 mm in diameter exhibited growth comparable to standard 60-mm dishes. In contrast, smaller chambers significantly impeded growth, even at identical seeding densities. Similar patterns were observed for HeLaGFP cells, while 16HBE14σ cells proliferated efficiently regardless of chamber size. Additionally, SH-SY5Y cells were studied in a 12-mm diameter sealed chamber to assess growth under restricted gas exchange conditions. Comparison with existing methods:Our findings underscore the limitations of small chamber sizes in microfluidic systems for SH-SY5Y cells, an issue not typically addressed by conventional methods. Conclusions:SH-SY5Y cell growth is highly sensitive to spatial constraints, with markedly reduced proliferation in chambers smaller than 10 mm. This highlights the need to carefully consider chamber size in microfluidic experiments to achieve cell growth rates comparable to standard culture dishes. The study also shows that while SH-SY5Y and HeLaGFP cells are affected by chamber size, 16HBE14σ cells are not. These insights are vital for designing effective microfluidic systems for bioengineering research.

The feasibility of CT simulation-free adaptive radiation therapy.

Novel on-board CBCT allows for improved image quality and Hounsfield unit accuracy. When coupled with online adaptive tools, this may have potential to allow for simulation and treatment to be completed in a single on-table session. To study the feasibility of a high-efficiency radiotherapy treatment workflow without the use of a separate session for simulation imaging. The dosimetric accuracy, overall efficiency, and technical feasibility were used to evaluate the clinical potential of CT simulation-free adaptive radiotherapy. Varian's Ethos adaptive radiotherapy treatment platform was upgraded with a novel CBCT system, HyperSight which reports image quality and Hounsfield unit accuracy specifications comparable to standard fan-beam CT. Using in-house developed MATLAB software, CBCT images were imported into the system and used for planning. Two test cases were completed on anthropomorphic phantoms equipped with small volume ion chambers (cross-calibrated to an ADCL traceable dose standard) to evaluate the feasibility and accuracy of the workflows. A simulated palliative spine treatment was planned with 8Gy in one fraction, and an intact prostate treatment was planned with 60Gy in 20 fractions. The CBCTs were acquired using HyperSight with default thorax and pelvis imaging protocols and reconstructed using an iterative algorithm with scatter removal, iCBCT Acuros. CBCTs were used for contouring and planning, and treatment was delivered via an online adaptive workflow. In addition, an external dosimetry audit was completed using only on-board CBCT imaging in an end-to-end head and neck phantom irradiation. An extended-field CBCT acquisition can be acquired in 12s, in addition to the time for longitudinal table shifts, and reconstructed in approximately 1min. The superior-inferior extent for the CBCT planning images was 38.2cm, which captured the full extent of relevant anatomy. The contouring and treatment planning for the spine and prostate were completed in 30 and 18min, respectively. The dosimetric agreement between ion chamber measurements and the treatment plan was within a range of -1.4 to 1.6%, and a mean and standard deviation of 0.41±1.16%. All metrics used in the external audit met the passing criteria, and the dosimetric comparison between fan-beam and CBCT techniques had a gamma passing rate of 99.0% with a criteria of 2%/2mm. Using an in-house workflow, CT simulation-free radiation therapy was shown to be feasible with acceptable workflow efficiency and dosimetric accuracy. This approach may be particularly applicable for urgent palliative treatments. With the availability of software to enable this workflow, and the continued advancement of on-treatment adaptation, single-visit radiation therapy may replace current practice for some clinical indications.

Investigation of the effect of HHO-assisted flame-jet ignition on in-cylinder combustion, engine performance, and environmental indicators in a propane-fueled SI engine

In this paper, a spark ignition (SI) engine is modified to operate by flame-jet ignition using oxy-hydrogen (HHO) gas in a small pre-combustion chamber (PCC) at partial load. The air-propane mixture in the main combustion chamber was ignited with an HHO-assisted flame jet, and the effects on in-cylinder combustion, engine performance, and environmental factors were investigated. In experimental studies, the SI engine was operated at 2300 rpm with a throttle opening of 1/2 at 24 different operating points generated by combining six different mixtures (λ = 0.9–1.4) and four different HHO flow rates (HHO = 0–1.0 l.min−1). The situation in which the HHO gas is not injected into the PCC is passive, while the situation in which it is injected is active. The findings showed that operating conditions with active PCC at λs significantly improved engine performance and environmental impact. The effect of active PCC was greater with lean mixtures (λ = 1.3–1.4) and decreased as the mixture shifted towards the rich (λ = 0.9). In addition, the effect of active PCC at all λs slowed down after 0.7 l.min−1 HHO flow rate. At λ = 1.4 and 1.0 l.min−1 HHO flow rate, where the highest effect occurs, Pmax and IMEP with active PCC are 76.09 % and 58.9 % increased, respectively; ISFC decreased by 38.3 % and ηt reached by 37 %; mfb’s of 0–10 %, 10–90 %, and 90–100 % 38.27, 20.83 %, and 47.62 % shorten, respectively; COVIMEP decreased by 6043 units; HC decreased by 95.18 %; CO2 and NOx emissions increased by 44.6 % and 24 %, respectively. In addition, at λ = 1.4, ΣE&SC decreased up to 164.5 €.kWh−1 which is 11 % lower than the lowest value of 183.5 €.kWh−1 obtained at passive PCC.

Study on adsorption and purification materials for ethylene in cold storage

In view of the lack of systematic quantitative and comparative studies on the purification effect of ethylene adsorbent in cold storage, starting from the selection of purification materials, this paper analyzed the purification effect of different zeolite materials on ethylene through a small test chamber, and screened out the best zeolite adsorbents used in self-made purification device. Combined with characterization analysis, purification efficiency evaluation and adsorption capacity of zeolite material, the removal performance of ethylene was investigated. The results showed that the zeolite samples with rough and porous surface showed better adsorption performance for ethylene. The larger the specific surface area and total pore volume, the stronger the adsorption capacity to ethylene. In addition, the presence of Na elements and mesoporous increased the exchange capacity and pore volume, which also played a certain role in the ethylene adsorption process. Experimental result demonstrates that clean air volume (CADR) of ethylene is 232 m3/h, the ethylene removal rate at 30 min is 98.19%, and the purification energy efficiency is 1.39. At the same time, the adsorption capacity of the selected zeolite sample is 1380.5 μg/g by dynamic adsorption experiment, and the service life of the filter element of the self-made purification device is estimated to be 166 days. This study can provide a theoretical basis for ethylene purification in cold storage.