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The role of Multidisciplinary Team and stepwise pelvic devascularisation to minimise...
Valentina LeThanh
Richard Bell

Valentina LeThanh

and 3 more

February 20, 2023
We describe the case of a Jehovah's witness patient undergoing pelvic exenteration for recurrent endometrial carcinoma, focusing on the preoperative, intraoperative and postoperative measures that allowed uncomplicated surgeries. Our case shows that pelvic exenteration is feasible in patients refusing blood products, if performed with a multidisciplinary team and careful planning.
Maternal SMC2 Is Essential for Embryonic Development via Participating in Chromosome...
Ke Xu
Jing-Yi Qiao

Ke Xu

and 9 more

February 20, 2023
During oocyte growth, maturation and zygote development, chromatin structure undergoes continuous changes to regulate different nuclear activities. Condensin plays an essential role in chromatin configuration. Here, through oocyte-specific conditional knockout of SMC2, a core component of the condensin complex, we showed that SMC2 is essential for the production of healthy eggs and early embryo development. Maternal SMC2 knockout caused chromosome condensation defects in oocytes, and subsequently inhibited proper pronuclear organization in zygotes. As a result, pronuclear function was impaired and DNA damage was accumulated, which prevented the development of embryos beyond the zygote stage.
Response to “Delay in AF ablation costs lives”
Andrew J. Sessions
Heidi May

Andrew J. Sessions

and 9 more

February 20, 2023
Response to “Delay in AF ablation costs lives”Andrew J. Sessions BS1, Heidi T. May, PhD, MSPH2, Brian G. Crandall, MD2, John D. Day, MD3, Michael J. Cutler DO, PhD2, Christopher A. Groh MD4, Leenapong Navaravong MD4, Ravi Ranjan MD, PhD4, Benjamin A. Steinberg MD, MHS4, T. Jared Bunch, MD4Corresponding Author: Dr. T. Jared BunchUniversity of Utah School of Medicine, Salt Lake City, Utah, USADepartment of Cardiology, Intermountain Heart Institute, Intermountain Medical Center, Salt Lake City, Utah, USASt. Marks Hospital, Salt Lake City, UtahDepartment of Internal Medicine, Division of Cardiology, University Hospital, Salt Lake City, Utah, USAAddress for correspondence: T. Jared Bunch, M.D.University of Utah School of Medicine Division of Cardiology, Department of Internal Medicine 50 N Medical Drive Salt Lake City, Utah 84132 Phone: 801-585-7676Short Title: Impact of delays in catheter ablationFunding : None
Invasive fungal infections in children with leukaemia in a tertiary hospital in Oman,...
Abdullah M.S. Al-Hatmi
Hind Al Hajri

Abdullah M.S. Al-Hatmi

and 6 more

February 20, 2023
Background: Invasive fungal disease (IFD) is a common and serious consequence of leukaemia in children and the incidence of these infections increased due to chemotherapy. We present the epidemiology of IFD in a cohort of children with leukaemia from a tertiary reference institution in Oman. Methods: A retrospective study of IFDs in pediatric patients with newly diagnosed or relapsed leukemia was conducted at the Royal Hospital in Muscat, Oman. From 2010 to 2017, IFD episodes in children with leukemia were evaluated retrospectively, taking into account age, gender, type of leukaemia, chemotherapy regimen, IFD detection phase, neutropenia, prophylaxis, diagnostic method, and treatment. Results: Between 2010 and 2017, 198 children with leukemia were admitted and treated at Royal Hospital. In retrospect, the IFI were defined as probable and proven in 53 % (17 patients) and 47% (15 patients) of the attacks. At 1.1:1, the male-to-female ratio was roughly equal. According to chest computed tomography (CT) scans, 65.6% of patients had radiological features of fungal infections. Positive fungal cultures were found in three patients’ bronchoalveolar lavage (BAL), 37.5% of whom had positive blood cultures, and 3% of whom had positive urine cultures. In 3 patients, invasive aspergillosis caused pulmonary IFD, accounting for 9.3% of all infection sites. Candidaemia was found in 28% of IFD patients. The most common organism was Candida tropicalis (15.6%), followed by Candida prapsilosis (6.25%). Conclusion: In children with leukemia, invasive fungal infection is common and serious. Despite aggressive treatment, mortality among these high-risk patients remains high.
The Transient Measurements by Voltage Transformer (VT) Based on Non-linear Model
Zhou Mu
Yuhan Jiang

Zhou Mu

and 8 more

February 20, 2023
Transient measurement is expected to be widely required in the future power system. One of the the most cost-effective ways to widely equip the power system with the transient measurements is to upgrade current voltage transformers to be enabled with transient measuring ability. This paper presents a algorithm-based technique involving the non-linear features of VT to enable CVT and PT with a wideband transient voltage measuring ability, including the methods of building the non-linear transient model and inverse calculation method based on the output voltage to recover the input voltage waveform. In this paper, the method of synthesizing the equivalent circuit model for a PT or a CVT is presented in detailed. Meanwhile, the inverse calculation method based on circuit theories and Bergeron equivalence as well as NR equivalence is also presented. The verification experiments were performed on a 110kV CVT and 10kV PT with the lightning impulses as the verification source. The experimental results show a good match to the input waveform recorded by standard divider.
Reliability Engineering Opportunities in Industry 4.0
Manuel Baro
Aida Reyes

Manuel Baro

and 1 more

February 20, 2023
Industry 4.0 is based on the internet of things, this means, that in industries or companies the value chain, including processes, products, hardware, and software, among others, exists the necessity to implement new knowledge technologies to implement and control Industry 4.0 interactions, in other words, with the advantages of industry 4.0 such as the used of real-time data, big data, blockchain, human-machine interaction, cyber-systems, among others, the electronic devices that allowed this interaction and electronic data interchange centralize, need to be in the highest possible reliability perform, aiming to be able to carry out all these activities safely and effectively. In this research, the objective is to introduce some general advantages of Industry 4.0 and how reliability engineering is an important ally in the performance of the functions of Industry 4.0. Then, this manuscript presents the necessary knowledge and applications of reliability engineering that can be implemented in Industry 4.0 as stress-strength analysis in the case of equal shape parameters β_(s= ) β_S ; stress-strength analysis β_(s ≠) β_S; Nonnormal capability index and Weibull Capability index, by using Weibull++ Software and mathematical procedure. Another target of this research is to demonstrate that by using reliability engineering it is possible to have better control in such a way that efficiency and productivity stay and even can increases. Also, reliability engineering represents security and stable processes. Finally, with the merging of Industry 4.0 and reliability engineering, the making decision process is more reliable decision-making.
Characteristics  and outcomes of pregnancies in the Maternal Outcomes Masterset (MOM)...
Liza Gibbs R
Ayad Ali K

Liza Gibbs R

and 6 more

September 11, 2023
A document by Liza Gibbs R. Click on the document to view its contents.
A rare Case of Pulmonary Embolism in a Mt. Kilimanjaro Recreational Hiker: A Case Rep...
Doreen Eliah
Gissela Nyakunga

Doreen Eliah

and 5 more

February 20, 2023
Pulmonary embolism (PE) is one of the rarest complications of high altitude sickness. Case reports are increasingly rising with the difficult to notice among HAPE patients given their presentation similarities. A high index of suspicion based on clinical examination and investigations should prompt a clinician to include or exclude it.
Treatment with 2-carba cyclic phosphatidic acid (2ccPA) promotes phenotypic switch of...
Wataru Nagata
Mari Gotoh

Wataru Nagata

and 6 more

February 20, 2023
Systemic lupus erythematosus (SLE) is an autoimmune disease associated with the production of double-stranded DNA (dsDNA) antibodies and other antibodies, that predominantly affects women, with a wide range of lesions. Although neuropsychiatric lupus erythematosus (NPSLE), characterized by neuropsychiatric symptoms related to cerebrovascular diseases or depression, ranks high in severity, and no specific treatments have yet been defined. 2-carba cyclic phosphatidic acid (2ccPA) is a derivative of cyclic phosphatidic acid isolated from a true slime mold Physarum polycephalum in 1992. Treatment with 2ccPA reportedly suppresses neuroinflammation and promotes tissue repair in mouse models of multiple sclerosis and traumatic brain injury. We performed behavioral tests in MRL/lpr mice as a model of NPSLE. The mice showed increased depression-like behaviors and decreased emotional responses to a new environment compared to the control mice. Treatment with 2ccPA significantly suppressed the behavioral abnormalities in MRL/lpr mice. In the prefrontal cortex and hippocampus, MRL/lpr mice showed a significantly elevated expression of CD68, a M1 phenotypic marker of microglia, which was significantly suppressed by 2ccPA treatment. In contrast, the expression of Arginase-1, a M2 phenotypic marker of microglia, was significantly increased by 2ccPA treatment. MRL/lpr mice showed higher plasma levels of anti-dsDNA antibody, which is mainly involved in the pathogenesis of SLE, compared to control mice. Treatment with 2ccPA decreased these levels in the MRL/lpr mice. These results suggest that 2ccPA treatment promotes phenotypic switch of M1 microglia to M2 and suppresses behavioral abnormalities in MRL/lpr mice.
Habitat protection and planning for Leonurus japonicus using the Maxent and Marxan mo...
Yongji Wang
Liyuan Xie

Yongji Wang

and 5 more

February 20, 2023
To predict suitable growing regions for Leonurus japonicus and to provide scientific sopport for the habitat conservation and the exploitation and utilization of germplasm resources under climate change conditions, this study combined niche and priority conservation models to assess the future potential distribution of L. japonicus in China. To this end, distribution points and samples of L. japonicus were gathered through online and field surveys. The Maxent model with optimized parameters was used for predicting the suitable habitats of L. japonicus at different stages, and the Marxan model was used to determine the priority of protected areas. The results showed that the highest temperature in the hottest month, the lowest temperature in the coldest month, the precipitation in the wettest month, the precipitation in the driest month, and altitude were the main environmental factors influencing the distribution of L. japonicus. Under the three climate change scenarios, the centroid of the suitable area of L. japonicus migrated northward, and the migration position tended to expand further northwest. In the future, there would be no significant niche differentiation of L. japonicus; the Marxan results showed that priority protected areas for L. japonicus were in southwestern central China, Lingnan, southern east China, and Guizhou. Overall, the results of this research can provide a strategy for the determination of priority protection areas for Leonurus japonicus in China.
Survey of New Applications of Geometric Algebra
hitzer
Manos Kamarianakis

Eckhard Hitzer

and 3 more

February 20, 2023
This survey introduces 101 new publications on applications of Clifford’s geometric algebras (GA) newly published during 2022 (until mid-January 2023). The selection of papers is based on a comprehensive search with Dimensions.ai, followed by detailed screening and clustering. Readers will learn about the use of GA for mathematics, computation, surface representations, geometry, image- and signal processing, computing and software, quantum computing, data processing, neural networks, medical science, physics, electric engineering, control and robotics.
An intentional random mathematical model of immigration: The case of Spain
R. Company
Lucas Jódar

R. Company

and 2 more

February 20, 2023
In this paper a random discrete mathematical population model of immigration is constructed using not only rational factors as the gradient of economy level among the host and issuing countries, the geography, or the regulation laws, but also hidden intentional factors such as political interests of governments, or the business of smuggling of migrants by mafias, which use the immigration practically as a weapon. These non-rational factors are modeled as sudden random arrival flow waves represented by a Poisson distribution. The period of study is short in order to make reliable the economic forecast of the next years. Although the study is focused in Spain, the approach is exportable to other geographic areas by adapting the data. Results are applied to predict the necessary national budget of the host country to afford this social phenomenon.
An empirical study of learning-to-rank for spare parts consumption in the repair proc...
Edson Duarte
Daniel de Haro Moraes

Edson Duarte

and 2 more

January 06, 2023
The repair process of devices is an important part of the business of many original equipment manufacturers. The consumption of spare parts, during the repair process, is driven by the defects found during inspection of the devices, and these parts are a big part of the costs in the repair process. In previous work we proposed a data-driven method for Supply Chain Control Tower solutions to provide support for the automatic check of spare parts consumption in the repair process. In this paper, we continue our investigation of a multi-label classification problem and explore alternatives in the learning-to-rank approach, where we simulate the passage of time using more data while training and comparing hundreds of Machine Learning models to provide an automatic check in the consumption of spare parts. We investigate the effects of different train set sizes, retraining intervals, models and hyper-parameter search using Bayesian Optimization. The results show that we were able to improve the trained models and achieve a higher mean NDCG@20 score of 86% when ranking the expected parts. Focusing on the most recent data, we achieve a NDCG@20 score of 90%, while obtaining a ratio of marked parts of just 4% of the consumed parts for use in alert generation.
An Encoder-Decoder Model with Interpretable Spatio-Temporal Component for Soil Temper...
Zhu yuheng
Xiaoning Li

Zhu yuheng

and 4 more

February 20, 2023
Soil temperature (ST) is a crucial land-surface parameter and accurate, interpretable ST predictions are essential for Earth system science applications. While deep learning methods have shown excellent performance in ST prediction, they are often referred to as “black box optimizers”, making it difficult to extract physical knowledge and gain interpretability. To address this issue, we developed the Encoder-Decoder Model with Interpretable Spatial-Temporal Component (ISDNM) to improve predictive accuracy and provide spatial-temporal interpretation of ST. The ISDNM model combines a CNN-encoder-decoder and LSTM-encoder-decoder to enhance the representation of spatial-temporal features and applies linear regression and UMAP to provide interpretable spatial-temporal insights into ST. The ISDNM outperforms traditional deep learning models such as Convolutional Neural Network, Long Short-term Memory, and Convolutional LSTM, making it a valuable tool to improve our understanding of ST’s spatiotemporal characteristics.
The Effects of Anti-Retroviral Therapy on Some Renal Parameters of Hiv Sero-Positive...
Gospel Ajuru
John  Ifenkwe

Gospel Ajuru

and 2 more

February 20, 2023
This study investigated the effect of antiretroviral therapy on some renal parameters of HIV seropositive individuals in Rivers State, Nigeria. A total of 300 HIV patients, who are undergoing treatment were recruited in this study, aged 20-70 years. They were classified into three groups; Group 1, made up of HIV sero-Positive infected individuals on highly antiretroviral therapy as the test subjects. Group 2 was HIV sero-Positive infected individual but not on highly active antiretroviral therapy as control 1. Group 3 was HIV sero-negative individual as control 2. Ethical approval for the study and informed consent from the participants was obtained. Renal parameters evaluated were Urea, Creatinine, Na, K, Ca, HCO3 and uric acid. The results were statistically significantly higher (P<0.05) in Na, K, HC03, Urea, creatinine and Ca of test subject and control I. compared to control II. Also, statistically significant increase (P<0.05) in Na, K, HC03, urea, Creatinine and Ca, of the test subject and control 1 compared to control II. In relation to sex there was also statistically significant increase (P<0.05) in Na, K, HCo3, urea, creatinine, Ca of test subject and control I compared to counted II in relation to Age group groups. Based on duration of therapy, for HIV positive patients who have been on Highly Active Antiretroviral Therapy (HAART) for 0-2years, there were no significant increase (P<0.005) in Na and calcium level, however there was statistically significant increase (P<0.05) in K, HC03, urea, creatinine, Ca. For 10 years and above, there was statistically significant increase (p<+0.05) in Na, K, HC03, urea, creatinine, Ca, compared to their respective control I and control II. This study demonstrated that long term administration of HAART to HIV infected positive subjects could lead to metabolic disorder which could predispose the patient to high risk of coronary heart disease.
Periodic average magnitude difference function for remote heart rate monitoring
Zhang Chi
Shaoming Wei

Zhang Chi

and 3 more

February 19, 2023
With the increasing attention on remote monitoring of human heart rate by radar, there is a need to develop a method that can estimate heart rate quickly and reliably. In this study, a new estimation method using a periodic average magnitude difference function (PAMDF) is proposed to estimate the heart rate from the radar signal. PAMDF advances the classical average magnitude difference function (AMDF) with the help of maximum likelihood (ML) theory. It operates in the time domain and estimates the heart rate by calculating the signal magnitude difference between all heartbeat periods. The proposed technique is more accurate than AMDF and allows rounding interpolation to improve resolution, while maintaining the low complexity advantage of AMDF. The algorithm was validated using radar data from a publicly available dataset.
A Low-Noise Blocker-tolerant Receiver with Balun-LNA and N-Path Mixer for Multiband W...
Jingzhi Yang
Zhenhao Weng

Jingzhi Yang

and 3 more

December 15, 2022
In this paper, a low-noise blocker-tolerant receiver that integrates Balun-LNA and N-Path mixer is proposed. Without on-chip balun, the LNA use a noise cancellation structure to constrain receiver noise. N-Path mixer and second-order low-pass TIA filter are used to implement the characteristics of blocker-tolerant. In 65nm CMOS process, the receiver occupies 0.09mm2 of active area, operates in the frequency range of 0.5--2 GHz and provides a 38dB conversion gain and a baseband bandwidth of 10 MHz. Consumes 29mW of power to achieve 2.8dB NF and 21.5dBm OOB-IIP3.
Influences of local and global context on local orientation perception
Jinfeng Huang
Yifeng Zhou

Jinfeng Huang

and 2 more

March 15, 2023
A document by Jinfeng Huang. Click on the document to view its contents.
Quantifying photodegradation of peatland-derived dissolved organic carbon in the coas...
Yongli Zhou
Moritz Müller

Yongli Zhou

and 3 more

February 21, 2023
The terrigenous dissolved organic carbon (tDOC) exported from the peatlands in Southeast Asia appears to be extensively remineralized in the shelf sea, but the processes that drive this remineralization remain unclear. Here, we combined incubation experiments and model simulations to quantify the rate and extent of photodegradation of tDOC in the Sunda Shelf Sea. Laboratory photodegradation experiments indicate that up to 74% of the peatland tDOC is potentially labile to photochemical remineralization. Based on our estimated apparent quantum yield for tDOC remineralization, modeled in-situ solar irradiance, and measured inherent optical properties of the water column, we simulated peatland tDOC photoremineralization for two coastal regions of the Sunda Shelf Sea. These simulation results show that natural solar radiation can directly remineralize 20±11% of tDOC over 2 years, which corresponds to the approximate residence time of water in the Sunda Shelf Sea, and that significant photobleaching of tDOC can occur in coastal waters over shorter time-scales. We further derived a simplified photochemical decay constant of 0.008–0.017day-1 for Southeast Asia’s peatland-derived tDOC, which can be used to parameterize the recently proposed UniDOM model framework. We conclude that direct photodegradation may be a greater sink for tDOC in Southeast Asia’s coastal ocean compared to higher latitudes, although it is insufficient to account for the total tDOC remineralization observed in the Sunda Shelf Sea.
Harnessing the strigolactone biosynthesis mutant lgs1 to combat food insecurity in Af...
Sylvia Mutinda
Muhammad Jamil

Sylvia Mutinda

and 7 more

February 21, 2023
Sorghum is a food staple for millions of people in sub-Saharan Africa, but parasitic weeds of the Striga genus greatly diminish its production. An efficient and cost-effective way of managing Striga in smallholder farms in Africa is to deploy resistant varieties. Here, we leverage genomics and the vast genetic diversity of sorghum – evolutionarily adapted to cope with Striga parasitism in Africa – to identify new Striga-resistant sorghum genotypes. We exploit a Striga resistance mechanism that hinges on essential communication molecules – strigolactones exuded by hosts to trigger parasite seed germination. We used the Sorghum Association Panel (SAP) to search for sorghum genotypes with a mutation on the LOW GERMINATION STIMULANT 1 ( LGS1) locus that makes them ineffective in inducing Striga germination. Our analysis led us to identify new lgs1 sorghum genotypes which we named SAP lgs1. SAP lgs1 had the SL exudation profile of known lgs1 sorghum whose hallmark is the production of the low inducer of germination, orobanchol. Laboratory and field resistance screens showed that the SAP lgs1 genotypes also exhibited remarkable resistance against Striga. Our findings have far-reaching implications for improving food security in Africa by potentially reducing crop losses due to Striga parasitism.
Depression and Anxiety in Infertility Patients
Yifeng Shen
Tingting Liao

Yifeng Shen

and 6 more

February 18, 2023
Depression and anxiety are common emotional responses among infertility patients, with research showing that they can negatively impact the mental well-being and quality of life of individuals struggling with infertility. This study aimed to conduct a bibliometric analysis of the existing literature on depression and anxiety in infertility patients, in order to shed light on the current state of research and identify potential areas for future study. The majority of research on depression and anxiety in infertility patients has been conducted in recent years, with a growing interest in the topic. Numerous investigations have assessed the effect of infertility treatments on patients' psychological health, with some examinations delving into the application of cognitive behavioral therapy and mindfulness-based stress reduction as potential methods for mitigating symptoms of depression and anxiety. Polycystic ovary syndrome, fertility preservation of cancer patients, COVID-19 pandemic, and assisted reproductive technology are also hot spots in this field. The findings of this bibliometric analysis highlight the importance of addressing depression and anxiety in infertility patients, and imply that further investigation is required to fully comprehend the intricate connections between infertility, depression, and anxiety.
A Text Mining Approach to Characterizing Interpersonal Stress among Individuals with...
Brooke Ammerman
Kenneth Tyler Wilcox

Brooke Ammerman

and 5 more

February 18, 2023
Objective: Interpersonal difficulties are salient among those with a history of NSSI and precede NSSI urges and behaviors. Yet, limited research has focused on identifying which aspects of interpersonal stress may confer risk for NSSI. Method: The current study aimed to leverage data from two samples (combined n=206; n=114 with NSSI history) of participant-driven interviews regarding a recent interpersonal stressor to enhance the field’s knowledge of interpersonal difficulties in relation to NSSI risk. Results: Using topic modeling to extract thematic information, analyses identified four main topics: daily difficulties; family members; adjectives/verbal fillers; and friendship/romantic relationships. Relationships between the topics and three predictors (i.e., NSSI history, emotion dysregulation, sample) were examined. In one sample, the proportion of ‘adjectives/verbal fillers’ was greater for participants with a NSSI history and at higher levels of emotion dysregulation. Across samples, for participants with a NSSI history, ‘adjectives/verbal fillers’ and ‘friendship/romantic partners’ increased with levels of emotion dysregulation. Conclusion: Findings highlight a greater use of adjectives and verbal fillers among individuals with a history of NSSI and higher levels of emotion dysregulation. This pattern of language may serve as an indicator of a specific aspect of emotion regulation difficulties that confers risk for NSSI.
The abundance of the potential pathogen Staphylococcus hominis in the air microbiome...
Marilena Aquino de Muro
Igor Shuryak

Marilena Aquino de Muro

and 8 more

February 18, 2023
The dental clinic air microbiome incorporates microbes from the oral cavity and upper respiratory tract (URT). This study aimed to establish a reliable methodology for air sampling in a dental clinic setting and quantify the abundance of culturable mesophilic aerobic bacteria present in these samples using regression modeling. Staphylococcus hominis, a potentially pathogenic bacterium typically found in the human oropharynx and URT, was consistently isolated. S. hominis was the most abundant species of aerobic bacteria (22% to 24%) and comprised 60% to 80% of all Staphylococcus spp. The study also assessed the susceptibility of S. hominis to 222nm-far-UVC light in laboratory experiments, which showed an exponential surface inactivation constant of k = 0.475 cm2/mJ. This constant is a critical parameter for future on-site use of far-UVC light as a technique for reducing pathogenic bacterial load in dental clinics.
Designs and operations of heat integrated reactors for thermochemically producing hyd...
Junjie Chen

Junjie Chen

February 21, 2023
Endothermic reactions performed in microreactors are driven using heat from an external source. However, the temperature of the gas stream providing the heat is limited by constraints imposed by the materials of construction. The present study is focused primarily upon the designs and operations of heat integrated reactors for thermochemically producing hydrogen from methanol by steam reforming. A symmetry boundary condition is used to model half of each system where symmetry exists. Computations are performed using grids with varying nodal densities to determine the optimum node spacing and density that would give the desired accuracy and minimize computation time. The final grid density is determined when the centerline profiles of temperature and species concentration do not show obvious difference. The second-order upwind scheme is used to discretize the mathematical model, and the semi-implicit method for pressure-linked equations algorithm is employed to solve for the pressure and velocity fields. The convergence is judged upon the residuals of all governing equations. The present study aims to provide a fundamental understanding of the designs and operations of heat integrated reactors for thermochemically producing hydrogen from methanol by steam reforming. Particular emphasis is placed upon the effect of various factors on the thermochemical steam reforming processes in heat integrated reactors. The results indicate that steam reforming produces hydrogen and carbon monoxide when heat is added to a catalytic reactor containing steam and hydrocarbons. Alternating channel parallel plate designs can be applied to thermally coupling endothermic steam reforming with combustion in neighboring channels. Balancing the heat requirements of an endothermic reaction with heat generated by an exothermic reaction flowing parallel to and on the opposite side of a separating plate is extraordinarily difficult since the endothermic reaction is likely to have a very different dependence upon concentration and temperature than the endothermic reaction. A convenient way to supply heat is to couple the endothermic reaction with an exothermic combustion reaction in the heat exchange channels. The process gas is raised in temperature and this energy can be utilized by the reforming process. The catalyst coating thickness depends upon the process proceeding within the catalyst matrix. The arrangement leads to improved heat transfer and therefore chemical conversion. Heterogeneous combustion aids in spreading the heat generation along the length of the channel and helps prevent hotspot formation.Keywords: Hydrogen production; Endothermic reactions; Discrete channels; Flow arrangements; Chemical conversion; Heterogeneous combustion
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