Exchange Function Research Articles

Knowledge Mapping to Improve Organization Capability in Internal Audit of Indonesia Stock Exchange

In the recent years, the Indonesian Capital Market saw a significant increase in terms of number of investors, daily transaction turnover, transaction frequency, and number of listed companies. This tremendous growth directly affects Indonesia Stock Exchange’s (IDX) to reconsider their knowledge management process to generate optimum results from carry out their responsibilities. As the sole capital market trading infrastructure provider in Indonesia, some of the stock exchange function can only be operated by using knowledge of IDX employee which acquired by years of working experience in IDX. The objectives in this study were to determine identify the essential knowledge and to define the essential knowledge that needs to be improved in IDX’s internal audit, and then propose an implementation plan to improve knowledge in IDX’s internal audit. The research method used is qualitative methodology through document analysis and key persons interviews interview which was conducted in April 2023. This study uses a variety of knowledge management approaches to address knowledge mapping, knowledge gaps, and knowledge loss. According to the study’s results, the author identifies knowledge gap and offers several recommendations regarding Knowledge Development Program to close the knowledge gap and Knowledge Retention Program to build on the knowledge that Internal Audit already possesses.

Learning alone together: Emergency-mode educational functions of international virtual exchange in times of the COVID-19 pandemic

AbstractVirtual exchange practices have been developed at universities for several years; however, the academic importance of VE has grown during the COVID-19 pandemic (Garcés & O'Dowd, 2020; Oswal, Palmer & Koris, 2021). As a result of the restrictions concerning physical mobility, VE has become a ‘first aid kit’ (Reiffenrath, de Louw & Haug, 2020) to continue students' international cooperation. However, at present, there is little research about the nature of students' VE practices during the pandemic COVID-19, particularly in relation to the functions of VE. Thus, the purpose of this study is to understand the characteristics of the special VE actions undertaken during the COVID-19 pandemic and to map out the educational functions and their prevalence through focus group interviews involving students who study at five different universities in Europe.The article introduces the term ‘emergency-mode’ VE programmes that combine activities of traditional VEs with tailor-made solutions to accommodate the challenges posed by the pandemic. The analysis shows new directions of VE in terms of its educational functions, identifying 1) developmental, 2) social, 3) instrumental, 4) emancipatory, 5) self-reflectional, 6) motivational, as well as 7) occupational functions. The article also presents the prevalence of these functions in the specific learning environments created due to the COVID-19 pandemic.

Marketing of bambara nut (okpa): Unlocking its potential for food and income security in Udenu Local Government Area, of Enugu State, Nigeria

The work was carried out to analyze marketing of Bambara nut : unlocking its potential for food and income security in Udenu Local Government Area of Enugu State, Nigeria. Considering its perceived high consumption in the study area and following some challenges in the supply of the produce. The specific objectives of the study described the various marketing functions performed by the marketers; estimated the cost and returns associated in bambara nut marketing in the study area; ascertained the factors that influence the net return from bambara nut marketers and identified the constraints faced by bambara nut marketers in the study area. Two (2) major markets in the study area were purposively selected; random sampling technique was used in selecting the respondents for the study. Data were collected from 80 respondents using a structured questionnaire. Data were analyzed using descriptive statistical tools such as; percentage, mean and frequencies, budgetary techniques and Ordinary Least Square (OLS) regression. The most common marketing functions performed by the marketers were identified to include exchange and physical functions. Result showed that mean net return from bambara marketing was ₦205251.12; cost benefit ratio was 1.26 and profitability index of the marketers was 0.21. The significant variables that affect net returns include household size (1%), marketing experience (1%), sex (1%), access to credit (10%), cooperative membership (1%), purchase cost (1%). However, high cost of transportation was the major constraint to marketing in the area. Marketers were recommended to undertake facilitating function which is used to describe those activities which make the exchange and physical distribution processes possible such as product standardization and grading, market promotion, financing, risk bearing and market intelligence.

On the mechanical, electronic, and optical properties of the boron nitride analog for the recently synthesized biphenylene network: a DFT study.

Recently, a new 2D carbon allotrope named biphenylene network (BPN) was experimentally realized. Here, we use density functional theory (DFT) calculations to study its boron nitride analogue sheet's structural, electronic, and optical properties (BN-BPN). Results suggest that BN-BPN has good structural and dynamic stabilities. It also has a direct bandgap of 4.5 eV and significant optical activity in the ultraviolet range. BN-BPN Young's modulus varies between 234.4[Formula: see text]273.2 GPa depending on the strain direction. Density functional theory (DFT) simulations for the electronic and optical properties of BN-BPN were performed using the CASTEP package within the Biovia Materials Studio software. The exchange and correlation functions are treated within the generalized gradient approximation (GGA) as parameterized by Perdew-Burke-Ernzerhof (PBE) and the hybrid functional Heyd-Scuseria-Ernzerhof (HSE06). For convenience, the mechanical properties were carried out using the DFT approach implemented in the SIESTA code, also within the scope of the GGA/PBE method. We used the double-zeta plus polarization (DZP) for the basis set in these cases. Moreover, the norm-conserving Troullier-Martins pseudopotential was employed to describe the core electrons.

A fluid–solid momentum exchange method for the prediction of hydroelastic responses of flexible water entry problems

The paper presents a Fluid Structure Interaction (FSI) method for hydroelastic water entry. The method assumes that the momentum exchange between the fluid and solid body can be used for the calculation of pressure, deformation and stresses arising during impact. The flexible fluid–structure interactions of flat plates entering water are solved using a computational code that employs the finite volume method to discretise both fluid and solid equations. This provides a better matching of momentum on the fluid–solid interface. The momentum arising in the solid body that emerges after the impact is defined as the momentum exchange, and is shown to increase linearly under the increase of non-dimensional impact speed. The ratio of the maximum pressure arising in an elastic body entering water to that of a rigid body is termed relative pressure and is shown to decrease linearly as a function of momentum exchange. The latter verifies the main hypothesis of this paper, namely that ‘the pressure acting on an elastic body can be predicted using an unsophisticated equation that uses the momentum exchange.’ The deformation and stresses arising in elastic plates entering water are demonstrated to be functions of momentum exchange and can be found using simple equations formulated via parametrisation of data. It is concluded that subject to further validation, the method could be extended for the prediction of hydroelastic response of other sections/bodies entering water.

Interesting effects of interleukins and immune cells on acute respiratory distress syndrome.

Acute respiratory distress syndrome (ARDS) is a medical condition characterized by widespread inflammation in the lungs with consequent proportional loss of gas exchange function. ARDS is linked with severe pulmonary or systemic infection. Several factors, including secretory cytokines, immune cells, and lung epithelial and endothelial cells, play a role in the development and progression of this disease. The present study is based on Pubmed database information (1987-2022) using the words "Acute respiratory distress syndrome", "Interleukin", "Cytokines" and "Immune cells". Cytokines and immune cells play an important role in this disease, with particular emphasis on the balance between pro-inflammatory and anti-inflammatory factors. Neutrophils are one of several important mediators of Inflammation, lung tissue destruction, and malfunction during ARDS. Some immune cells, such as macrophages and eosinophils, play a dual role in releasing inflammatory mediators, recruitment inflammatory cells and the progression of ARDS, or releasing anti-inflammatory mediators, clearing the lung of inflammatory cells, and helping to improve the disease. Different interleukins play a role in the development or inhibition of ARDS by helping to activate various signaling pathways, helping to secrete other inflammatory or anti-inflammatory interleukins, and playing a role in the production and balance between immune cells involved in ARDS. As a result, immune cells and, inflammatory cytokines, especially interleukins play an important role in the pathogenesis of this disease Therefore, understanding the relevant mechanisms will help in the proper diagnosis and treatment of this disease.

Potential direct role of synuclein in dopamine transport and its implications for Parkinson's disease pathogenesis

Parkinson Disease (PD) is a progressive neurodegenerative disorder that is caused by dysfunction and death of dopaminergic neurons. Mutations in the gene encoding α-synuclein (ASYN) have been linked with familial PD (FPD). Despite important role of ASYN in PD pathology, its normal biological function has not been clarified, although direct action of ASYN in synaptic transmission and dopamine (DA+) release have been proposed. In the present report we propose a novel hypothesis that ASYN functions as DA+/H+ exchanger that can facilitate transport of dopamine across synaptic vesicle (SV) membrane by taking advantage of proton gradient between SV lumen and cytoplasm. According to this hypothesis, normal physiological role of ASYN consists of fine-tuning levels of dopamine in the SVs based on cytosolic concentration of dopamine and intraluminal pH. This hypothesis is based on similarity in domain structure of ASYN and pHILP, a designed peptide developed to mediate loading of lipid nanoparticles with the cargo molecules. We reason that carboxy-terminal acidic loop D2b domain in both ASYN and pHILP binds cargo molecules. By mimicking DA+ association with E/D residues in D2b domain of ASYN using Tyrosine replacement approach (TR) we have been able to estimate that ASYN is able to transfer 8–12 molecules of dopamine across SV membrane on each DA+/H+ exchange cycle. Our results suggest that familial PD mutations (A30P, E46K, H50Q, G51D, A53T and A53E) will interfere with different steps of the exchange cycle, resulting in partial loss of dopamine transport function phenotype. We also predict that similar impairment in ASYN DA+/H+ exchange function also occurs as a result on neuronal aging due to changes in SV lipid composition and size and also dissipation of pH gradient across SV membrane. Proposed novel functional role of ASYN provides novel insights into its biological role and its role in PD pathogenesis.

Peculiarities of information and analytical support in conducting epidemiological surveillance in the public health system

Objective. The purpose of this study was to determine the features of information and analytical support in the conduct of epidemiological surveillance in the system of public health institutions. Methods. The research was performed on the basis of the following methods: dialectical - to determine the essence of information and analytical support of public health institutions; functional, comparative analysis - to analyze the activities of the State Institution "Kirovohrad Regional Center for Disease Control and Prevention of the Ministry of Health of Ukraine"; model, integrated approaches - to develop a model of information and analytical support for the activities of public health institutions and measures for its implementation in practice; methods of statistical analysis - to determine the features of research on environmental objects and the dynamics of infectious diseases. Results and discussion. A study of the functioning of public health institutions, in particular the Kirovohrad Regional Center for Disease Control and Prevention of the Ministry of Health of Ukraine, identified general areas for development and implementation to improve public health. Conclusions : In the process of improving the information and analytical support of the activities of epidemiological surveillance institutions in the public health system, its key aspects of development were presented. More detailed solutions to public health problems were suggested. Tasks have been formulated to improve the information and analytical support of the activities of epidemiological surveillance institutions in the public health system. It is established that all these aspects, which are related to improving the information and analytical function of public health institutions, for full use must be integrated into a single automated system with the creation and maintenance of information databases and information exchange functions, including real time. The structure of the model of information and analytical support for the activities of public health institutions has been developed. The main elements of the information-analytical system of epidemiological surveillance institutions in the public health system should be: databases of necessary information, system of indicators of public health, state of the environment, data processing system, communication system, transmission, information protection, system forecasting changes in public health indicators, the base of standard management decisions in certain circumstances (combinations of indicators), equipped with digital user workstations.

Associations between the muscle quality index and adult lung functions from NHANES 2011-2012.

The muscle quality index (MQI), as an important component of sarcopenia, is defined as the ratio of muscle strength to muscle mass. Lung function, is a clinical indicator to assess ventilation and air exchange function. This study investigated the relationship between lung function indices and MQI in the NHANES database from 2011 to 2012. This study included 1,558 adults from the National Health and Nutrition Examination Survey from 2011 to 2012. Muscle mass and muscle strength were assessed using DXA and handgrip strength, and all participants underwent pulmonary function measurements. Multiple linear regression and multivariable logistic regression were used to assess the correlation between the MQI and lung function indices. In the adjusted model, MQI was significantly correlated with FVC% and PEF%. And, after quartiles of MQI in Q3, where FEV1%, FVC%, and PEF% were all associated with MQI, in Q4, a lower relative risk of a restrictive spirometry pattern was linked to increased MQI. Compared to the lower age group, the relationship between the MQI and lung function indices was more significant in the higher age group. There was an association between the MQI and lung function indices. Furthermore, in the middle-aged and older adult populations, lung function indicators and restrictive ventilation impairment were significantly associated with MQI. This implies that improving lung function through muscle training may be beneficial to this group.

Abstract A022: Translation initiation factor 2B (eIF2B) stimulates mutant KRAS function in cancer

Abstract KRAS mutations appear with high frequency in colorectal, lung and pancreatic cancers, which are the three leading causes of new cancer deaths worldwide. Mutant KRAS is preferentially bound to GTP resulting in continuous cell proliferation. Mutant KRAS exposes cells to oncogenic forms of stress (i.e. genotoxic, metabolic, proteostatic stress), which disrupt proliferation and tissue homeostasis. To cope with stress, cells engage pro-adaptive mechanisms, which act in favor of mutant KRAS to transform cells. An important adaptation mechanism to stress acts at the level of mRNA translation and involves the functional interplay between the translation initiator factors eIF2 and eIF2B. Phosphorylated eIF2 mediates a translational and transcriptional reprogramming to promote adaptation under stress, a process that is antagonized by the guanine exchange function (GEF) of eIF2B. We demonstrate the physical interaction between mutant KRAS and eIF2B by mass spectrometry. Using genetic approaches, we show that eIF2B is required for the survival and proliferation of tumor cells with KRAS mutations via the stimulation of MAPK signaling. We also show that eIF2B contributes to increased resistance of tumor cells to pharmacological inhibition of mutant KRAS forms. Genetic inactivation of eIF2B promotes the formation of mutant KRAS-GDP complexes whereas its pharmacological stimulation facilitates mutant KRAS-GTP complex formation in tumor cells; this data supports a potential GEF function for eIF2B towards mutant KRAS. Cell imaging experiments provide strong evidence for the implication of eIF2B in the association of mutant KRAS with the plasma membrane of tumor cells. Our findings reveal a stimulatory role of eIF2B in mutant KRAS signaling and provide a previously unidentified link between mutant KRAS and mRNA translation with implications in the growth and treatment of cancers with KRAS mutations. Citation Format: Hyungdong Kim, Nour Ghaddar, Laleh Ebrahimi Ghahnavieh, Shuo Wang, Kwang-Jin Cho, Atsuo Sasaki, Antonis E. Koromilas. Translation initiation factor 2B (eIF2B) stimulates mutant KRAS function in cancer [abstract]. In: Proceedings of the AACR Special Conference: Targeting RAS; 2023 Mar 5-8; Philadelphia, PA. Philadelphia (PA): AACR; Mol Cancer Res 2023;21(5_Suppl):Abstract nr A022.

Polarization-Independent Reconfigurable WDM-MDM Hybrid Multiplexer on Silicon Photonics Platform

In order to increase the communication capacity of optical links, hybrid multiplexing technology has attracted a lot of interest. In this letter, we have proposed and experimentally demonstrated a polarization-independent silicon hybrid multiplexer with two-mode channels and four-wavelength channels based on an active polarization control scheme. It consists of eight on- chip polarization controllers, one <inline-formula xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink"> <tex-math notation="LaTeX">$8\times $ </tex-math></inline-formula> 8 arrayed waveguide grating multiplexer, and one mode switch. Experimental results show that the polarization-dependent loss is about 0.6 dB. And the crosstalk is less than −18 dB for an arbitrarily polarized light. At the same time, this device also features a signal exchange function between the TE0 and TE1 modes for the aggregated throughput of wavelength channels.

ФОРМУВАННЯ ФІНАНСОВО ПЕРСПЕКТИВНОЇ ІДЕЇ: БІРЖОВЕ ПІДПРИЄМНИЦТВО

Over the past two decades, the exchange environment has changed significantly, digitized, become more flexible and moved to other platforms. Technological, low-cost trading platforms contributed to intensifying competition between traditional exchanges. Conventional cooperative exchanges had neither the structural flexibility nor the financial agility to actively compete with new trading platforms. Digitization of exchanges leads to the emergence of new regulatory problems; therefore it is important that regulators and exchange management clearly understand the process of forming a financially promising idea and exchange position, are able to assess new risks and effectively solve them. The purpose of the study is to develop an approach to determining the value of the process of initiation, categorization and implementation of financially promising ideas and projects from the point of view of service on exchange platforms and its introduction as an evaluation of stock market instruments. Scientific publications and monographic editions, magazine articles and materials of scientific and practical conferences became the methodological basis of the research. Content analysis of scientific periodicals was used during the research; comparative critical analysis of existing approaches and methods of analysis of financial stability and tax burden; analysis of economic activity of enterprises in the aerospace industry; statistical methods of analysis. The main hypothesis of the study was the assumption of the possibility of forming an approach to determining the meaning of the process of initiation, categorization and implementation of financially promising ideas and projects from the point of view of service on exchange platforms and introduction as stock market tools. Presenting main material. The article examines the main aspects of the formation of an approach to determining the meaning of the process of initiation, categorization and implementation of financially promising ideas on stock exchanges. It is emphasized that financial ecology has significantly affected the exchange environment, forcing exchanges to review their roles and change the policy of their strategies regarding the formation of financially promising ideas. The stock exchange is presented as a commercial organization that produces a single product – price. The originality and practical significance is defined in the development of a methodical approach to determining the value of the process of initiation, categorization and implementation of financially promising ideas and projects from the point of view of service on exchange platforms and its introduction as an evaluation of stock market instruments. Conclusions and prospects for further research. The study analyzed the transformation of the stock exchange from the market model to the enterprise model. The role of the main functions of the stock exchange was reviewed and an analysis of the formation of an approach to determining the meaning of the process of initiation, categorization and implementation of financially promising ideas and projects from the point of view of service on stock exchange platforms and its introduction as an evaluation of stock market instruments was carried out

Blockchain Enhanced Stock Trading Application

Stock exchange works and functions in a very inconvenient and hectic way because of post-trade processes which are cost-inefficient, time-consuming and can be prone to numerous risks. This motivates us to experiment with new technologies like blockchain which has immense potential to change the process of post-trading. In this paper, we propose an implementation of a stock trading application built on Hyperledger Fabric, a hybrid blockchain architecture. The network for our application is built using Hyperledger Composer framework. All the transactions done on the client app are recorded and appended to the Fabric with the help of a REST server. Fabric contains various security measures such as Access Control Lists and channels to ensure only authorized users to have access to those transactions. Before the users can perform any transactions, they will be given an identity card containing the certificates and credentials required to access the blockchain network. With our approach, we aim to significantly cut the transaction costs of exchanging shares and bring about a seamlessly efficient platform where participants would confirm trades via a distributed ledger

Leaf porous structure Inspired packaging film for fruits preservation and monitoring CO2 concentration of package

The preservation of fresh fruit and vegetables is always a challenge. Equilibrium modified atmosphere packaging (EMAP) is ideal for preserving fresh produce. The gas transmission and selectivity of EMAP films is crucial for achieving atmospheric equilibrium in packaging. Inspired by leaf porous structure regulating their gas exchange function, we selected natural porous diatomite as the gas channel and modified it with polyethyleneimine (PEI). By introducing diatomite into the film matrix of CNFs, the gas transmission and CO2/O2 selectivity of EMAP films were regulated. The atmosphere in all the packages of EMAP films reached equilibrium within 24 h, which kept the fruit in low intensity aerobic respiration. The EMAP film of DgP7.5 (O2 transmission rate 43.33 cc m−2 day−1 bar−1, CO2/O2 selectivity 1.56) was found to be the most suitable for packaging litchis and green plums. Diatomite with porous structures will provide a design concept for EMAP films.

Vibrational characterization of the various forms of (solvated or unsolvated) mobile proton in the solid state. Advantages, limitations and open questions

A didactic review of (Raman, infrared and neutron) vibrational spectroscopy procedures to study mobile protonic species (H2O, H3O+, H5O2+, “H+”, NH4+, etc.) in solid hydrates, crystals and ceramics is proposed on the basis of paper published since 1970s. Three materials are taken as representative examples: hydrated uranyl phosphate (HUP), oxonium, hydroxonium and ammonium beta- and beta“-aluminas and nominally anhydrous strontium/barium zirconate perovskite. Particular attention is given to the advantages of isotopic substitution and dilution measurements as a function of temperature and partial ion exchange. The vibrational signatures that we consider as being able to serve as references for the different kinds of proton species observed in the proton conductors are presented. We also discuss the signature of protonic species giving no vibrational signature - or whose Raman and infrared signatures are too weak to be clearly detected – that need to be better characterized and understood. The presence of a strong incoherent inelastic neutron scattering background appears characteristic of (mobile) proton conductors.

CLCN7, a gene shared by autosomal recessive and autosomal dominant osteopetrosis.

After the discovery of abundant v-ATPase complexes in the osteoclast ruffled membrane it was obvious that in parallel a negative counter-ion needs to be transported across this membrane to allow for efficient transport of protons into the resorption lacuna. While different candidate proteins were discussed the osteopetrosis phenotype of Clcn7 knockout mice suggested that the chloride/proton-exchanger ClC-7 might be responsible for transporting the negative charge. In the following, individuals with autosomal recessive osteopetrosis (ARO) were found to carry biallelic CLCN7 pathogenic variants. Shortly thereafter, heterozygous pathogenic variants were identified as the exclusive cause of autosomal dominant osteopetrosis type 2 (ADO2). Since in most cell types other than osteoclasts ClC-7 resides in late endosomes and lysosomes, it took some time until the electrophysiological properties of ClC-7 were elucidated. Whereas most missense variants lead to reduced chloride currents, several variants with accelerated kinetics have been identified. Evidence for folding problems is also known for several missense variants. Paradoxically, a heterozygous activating variant in ClC-7 was described to cause lysosomal alteration, pigmentation defects, and intellectual disability without osteopetrosis. The counter-intuitive 2 Cl-/H+ exchange function of ClC-7 was shown to be physiologically important for intravesicular ion homeostasis. The lysosomal function of ClC-7 is also the reason why individuals with CLCN7-ARO can develop a storage disorder and neurodegeneration, a feature that is variable and difficult to predict. Furthermore, the low penetrance of heterozygous pathogenic CLCN7 variants and the clinical variability of ADO2 are incompletely understood. We aim to give an overview not only of the current knowledge about ClC-7 and its related pathologies, but also of the scientists and clinicians that paved the way for these discoveries.

Electronic Health Record Use and Perceptions among Urologic Surgeons.

Electronic health records (EHRs) have become widely adopted with increasing emphasis on improving care delivery. Improvements in surgery may be limited by specialty-specific issues that impact EHR usability and engagement. Accordingly, we examined EHR use and perceptions in urology, a diverse surgical specialty. We conducted a national, sequential explanatory mixed methods study. Through the 2019 American Urological Association Census, we surveyed urologic surgeons on EHR use and perceptions and then identified associated characteristics through bivariable and multivariable analyses. Using purposeful sampling, we interviewed 25 urologists and applied coding-based thematic analysis, which was then integrated with survey findings. Among 2,159 practicing urologic surgeons, 2,081 (96.4%) reported using an EHR. In the weighted sample (n = 12,366), over 90% used the EHR for charting, viewing results, and order entry with most using information exchange functions (59.0-79.6%). In contrast, only 35.8% felt the EHR increases clinical efficiency, whereas 43.1% agreed it improves patient care, which related thematically to information management, administrative burden, patient safety, and patient-surgeon interaction. Quantitatively and qualitatively, use and perceptions differed by years in practice and practice type with more use and better perceptions among more recent entrants into the urologic workforce and those in academic/multispecialty practices, who may have earlier EHR exposure, better infrastructure, and more support. Despite wide and substantive usage, EHRs engender mixed feelings, especially among longer-practicing surgeons and those in lower-resourced settings (e.g., smaller and private practices). Beyond reducing administrative burden and simplifying information management, efforts to improve care delivery through the EHR should focus on surgeon engagement, particularly in the community, to boost implementation and user experience.

Arabidopsis translation factor eEF1Bγ impacts plant development and is associated with heat-induced cytoplasmic foci.

The important role of translational control for maintenance of proteostasis is well documented in plants, but the exact mechanisms that coordinate translation rates during plant development and stress response are not well understood. In Arabidopsis, the translation elongation complex eEF1B consists of three subunits: eEF1Bα, eEF1Bβ, and eEF1Bγ. While eEF1Bα and eEF1Bβ have a conserved GDP/GTP exchange function, the function of eEF1Bγ is still unknown. By generating Arabidopsis mutants with strongly reduced eEF1Bγ levels, we revealed its essential role during plant growth and development and analysed its impact on translation. To explore the function of the eEF1B subunits under high temperature stress, we analysed their dynamic localization as green fluorescent protein fusions under control and heat stress conditions. Each of these fusion proteins accumulated in heat-induced cytoplasmic foci and co-localized with the stress granule marker poly(A)-binding protein 8-mCherry. Protein-protein interaction studies and co-expression analyses indicated that eEF1Bβ physically interacted with both of the other subunits and promoted their recruitment to cytoplasmic foci. These data provide new insights into the mechanisms allowing for rapid adaptation of translation rates during heat stress response.

Oxygenation index and NT-proBNP as predictors of pulmonary hypertension and ventilation/perfusion mismatch in acute pulmonary embolism.

The magnitude of pulmonary artery pressure (PAP) and the extent of ventilation/perfusion (V/Q) mismatch are essential for assessing the prognosis of acute pulmonary embolism (APE). We aimed to develop a model for predicting the status of the pulmonary circulation and arterial gas exchange functions using serum levels of cardiac biomarkers and arterial oxygenation index (OI) values. This single-center, retrospective observational cohort study included 224 patients with APE. Multivariate linear regression and Poisson regression were used to test the statistical association between cardiac biomarkers, OI, PAP, and V/Q mismatch. Diagnostic efficiency was calculated from a receiver operating characteristic (ROC) curve. Serum levels of troponin I (TNI), N-terminal pro-brain natriuretic peptide (NT-proBNP), and arterial OI magnitude significantly correlated with PAP and V/Q mismatches (P < 0.05). Multivariate linear regression showed that NT-proBNP serum levels (β = 0.002, P < 0.001) and OI values (β = -0.022, P = 0.001) significantly influenced PAP. Arterial OI (β = -0.039, P < 0.001) had a significant influence on the percentage of pulmonary vascular obstruction (PVO) as determined by perfusion scanning. Poisson regression showed that OI (odds ratio: 0.995, p < 0.001) was a predictor of the number of lung segments with V/Q mismatches. ROC area under the curve (AUC) values of NT-proBNP and OI predicting pulmonary hypertension were 0.716 and 0.730, respectively, and for V/Q mismatch scanning, the results were 0.601 and 0.634, respectively. Arterial OI and serum levels of cardiac biomarkers may be used as indicators of pulmonary hypertension and V/Q mismatch.

The leucine zipper EF-hand containing transmembrane protein-1 EF-handis an atypical tripartite calcium, temperature, and pH sensor.

Mitochondrial calcium (mtCa2+) is integral to ATP production; however, excessive Ca2+ leads to cell death. Both these processes are crucial to cellular function, and thus mtCa2+ homeostasis is tightly regulated. Leucine zipper EF-hand containing transmembrane protein-1 (LETM1) is an essential inner-mitochondrial membrane protein that regulates mtCa2+ through exchange of Ca2+ for protons (H+). LETM1 haploinsufficiency is associated with Wolf-Hirschhorn syndrome, characterized by microcephaly, growth retardation, and epileptic seizures, indicating a fundamental function for LETM1 in humans. LETM1 contains a conserved Ca2+ binding EF-hand motif (EF1). Deletion of EF1 abrogates LETM1 mediated mtCa2+ flux, but the precise mechanism by which EF1 regulates exchanger function remains unknown. To begin understanding the role of EF1 in LETM1 function, we biophysical and structurally characterized isolated EF1. Our data show that EF1 exhibits augmented α-helical secondary structure, solvent exposed hydrophobicity and oligomerization in the presence of Ca2+ due to a weak but specific, Ca2+-binding affinity. The low affinity is, in part, due to a terminal Asp within the binding loop, where mutation to Glu increases the affinity ∼4-fold. EF1 is structurally sensitive to pH changes within the physiological range for mitochondria, and remarkably, unfolds at high and low temperatures. Using solution NMR spectroscopy, we reveal that EF1 adopts an atypical EF-hand arrangement by pairing with an upstream loop-helix motif. Collectively, our data suggest that EF1 functions as a divergent multipartite environmental sensor within the EF-hand protein family by adopting an inimitable three-helix EF-hand domain arrangement in LETM1.