bluuebunny/crossref_metadata_2025 huggingface dataset:
The effect of roller pressure and feed rate on hides squeezing
Authors: Bahadirov Gayrat , Tsoy Gerasim , Nabiev Ayder
Published: August 2023

The article presents the results of experimental studies of the process of extracting excess liquid from a water-saturated hide. The experiments were conducted in two options: using a rigid base plate and a cermet base plate for the feed mechanism of the roller machine. In the study, samples of a wet hide on rigid and cermet base plates were pulled between rotating squeezing rollers using conveyor chains. Mathematical dependences of the amount of liquid removed from a wet hide on its feed rate and the pressure of the squeezing rollers were obtained for two special options. The experimental results showed a significant increase in the efficiency of the squeezing process of a wet hide due to the use of a cermet base plate in comparison with a rigid base plate.
Fire extinguishing systems for dump trucks
Authors: Pashkov Dmitry , Turgenev Ilya , Semenov Alexey
Published: August 2023

The paper presents a classification of fire extinguishing systems for dump trucks. The principles of fire-extinguishing systems operation are given according to the method of actuation and purpose of applied extinguishing agents. Manufacturers of fire-extinguishing systems for mine dump trucks are marked, and technical characteristics of their systems are represented. As a result of the research, it has been determined that the main direction of development of fire-extinguishing systems is connected with extinguishing of class E fires, because of increase in demand on CW with electromechanical transmission, the most perspective systems of fire-extinguishing are systems with automatic switching, with possibility of manual switching.
The formation of alloy based on Al-Ti-B system by electroslag process involving dispersed engineering waste
Authors: Safronov Nikolay , Kharisov Lenar , Fazliyev Marat
Published: August 2023

In this article presents technological process of manufacturing Al-Ti-B rod master alloy by electroslag casting is proposed and investigated. Aluminum alloy chip waste of a grade AK7, commercial titanium of a grade VT1-00 and amorphous boron of a grade A were used as starting materials. The consumable electrode is a product in the form of a rod obtained by mouthpiece pressing of a mixture of crushed starting materials in a mass ratio of AK7 : VT1-00 : amorphous boron = 97:2:1. According to the proposed technology and the ratio of starting materials in the charge composition, an experimental bar material of the Al-Ti-B ligature was obtained, electron microscopic, micro-X-ray spectral studies, the stereometric analysis of the structure which showed the priority interaction of titanium with boron.
Rheological properties magnetically elastic material samples under extreme compression modes
Authors: Minaev Andrey , Valiev Hammat , Stepanov Gennady
Published: August 2023

The magnetoelastic material samples in compression tests are investigated. The studied materials rheological properties are carried out on an automated testing machine. Compressive moduli changes diagrams depending on deformation values up to limiting extreme values are plotted. Transition ranges from linear to nonlinear, longitudinal compression moduli, depending on the specimen compression degree, were fixed. Repeated tests on specimens showed a decrease in the compression moduli by several times. In revealing rheological properties the investigated materials shape memory effect is demonstrated.
Solution of contact problems of anisotropic plates bending on an elastic base using the compensating loads method
Authors: Velikanov Peter
Published: August 2023

In critical structures used elements consisting of anisotropic materials with concentrated force or moment applied to them are often found. In order to equalize the internal force factors, as well as to ensure the required strength and rigidity of the structure, in places where a local load is applied, it is necessary to strengthen the plate with a rigid lining (stamp). There are several ways to solve contact problems. The way seems simpler if it is possible to determine the exact fundamental solution (FS) for the plate. The exact FS significantly reduces the amount of computational work due to the fact that the boundary conditions and the conditions of conjugation of solutions at the boundary of the contact area are met in advance. It remains only to formulate the conditions for the compatibility of movements in the contact area. With this formulation, the integral equation of the contact condition becomes a singular integral equation of the first kind. Such equations are reduced by regularization to Fredholm equations of the second kind and the problem becomes mathematically and physically correct. The paper considers contact problems without taking into account tangential interaction between objects. For such problems, the following way of simplification is possible: replacing the singular core for a half-space with a core for a layer of constant thickness modeled by an elastic base with a single base coefficient. Such a replacement for thin shells is quite justified and gives solutions that are in good agreement with the solutions of the theory of elasticity. The deflection of the plate is sought using the compensating loads method. To work out the methodology, a test contact problem was solved.
Effects of the single-lap joint on fatigue strength of metals with different surface coatings: a numerical simulation
Authors: Baykara Celalettin , Teke Ibrahim T. , Ertas Ahmet H.
Published: August 2023

Due to their low cost and ease of use, adhesives are frequently used in the industry. Selecting adherents and adhesives is essential when thinking about a construction that uses them. A fatigue study is therefore required to determine the best adherents and adhesives. In this situation, a prediction model must be incorporated into the process. In this study, Single-lap joint (SLJ) was chosen. Specimens with uncoated, primed, and cataphoresis-treated surfaces on DC01 steel sheet surfaces have been taken into account. A numerical solution was produced to obtain the fatigue life of the structures. Results indicate that the produced approach can provide an accurate estimate of fatigue resistance of different bonding methods including adhesive joints with various coating and adhesive thicknesses combined with adhesive techniques.
Influence of air temperature on thaw depth of a road foundation
Authors: Galkin A.F. , Plotnikov N.A. , Pankov V.Yu.
Published: August 2023

The expected thaw depth of the foundation soil is one of the parameters influencing the selection of technical solutions of road design in the permafrost area. The purpose of this research is a quantitative assessment of the degree of influence of air temperature on thaw depth of the road foundation soil in the permafrost area. A standard formula to calculate thaw depth of melting bodies of flat symmetry obtained through a solution of the one phase Stefan problem at boundary conditions of the first kind was used for the analysis. An algorithm using an analytical formula to assess the influence of the main initial parameters and accuracy of their determination on the resulting value, the thaw depth of the soil, is proposed. The results of the calculations are presented in a graphical form displaying the influence of average air temperature and the accuracy of its setting on the thaw depth of the road foundation soil. It was determined that the degree of change in thaw depth is non-linear and depends on both the average air temperature and on the accuracy with which it is set. For every average air temperature value there is a specific measure of required accuracy for thermal calculations so that the error of thaw depth determination does not exceed the permitted error. A 3D chart showing the expected percentage error in thaw depth forecasting depending on the average air temperature and the accuracy of its setting for an array of initial values was created.
High temperature resistant rubber asphalt
Authors: Opukenigara Opukenigara , Putri Elsa Eka , Adji Bayu Martanto , Hakam Abdul
Published: August 2023

Rubber Asphalt is the asphalt with rubber addition. The addition of rubber to asphalt was expected to have higher stiffness and longer durability that can be identified by its properties, that are softening point, penetration and ductility. The 60/70 penetration asphalt has been mixed with 7% rubber. Mixing of rubber with asphalt was quite a challenge. The liquid rubber or solid rubber should be processed through prevulcanization in the asphalt plant. The properties of the rubber asphalt have been investigated in the laboratory of BPJN West Sumatera. Hence, the properties of rubber asphalt have followed the Bina Marga standard for pavement mixture, i.e. the softening point value is >52°C, the ductility is more than 140 cm, and the burning point was above the 310°C. By determined the index penetration of the rubber asphalt that is. Thus, it can be concluded that the 7% rubber asphalt has resulted in the higher resistance to higher temperature binder.
Innovative types of strategy applied in businesses and example from application
Authors: Akbarov Tamerlan
Published: August 2023

Innovative types of strategies applied in enterprises are more in focus in today's business world. These types combine the different goals and objectives of businesses, resulting in innovation and creativity. Innovative strategies include the use of various new ideas, technologies and services provided to customers and their application in various business areas of the enterprise. These types create new values for the enterprise's customers or investors and increase their competitiveness. Several examples can be given for enterprises in the application of innovative strategies. For example, Apple has successfully implemented innovative strategies in the field of technology by introducing new products such as iPhone and iPad. This strategy increases Apple's investment value by providing innovation to customers. Also, Amazon, characteristically, applies an innovative strategy in the presentation of online stores. Amazon leverages technology to make customer orders faster and easier. This type of innovative strategy improves the customer experience in the shopping process and increases the likelihood of repeat orders.
Model of determination and forecasting of prices of forest products using the example of pulp
Authors: Sushko Olga , Plastinin Alexandr
Published: August 2023

The paper presents the problems of the development of the Russian forest complex at the present stage, which are confirmed by a decrease in the volume of production and export of forest products. Fluctuations in global and domestic prices for forest products create real problems of sustainable and effective development of the forest complex. Many factors determine the dynamics of timber prices and affect various components of price dynamics. As the correlation analysis showed, the main influence on the trend component of pulp prices on the world market and the Chinese market is exerted by: the change in GDP per capita as a percentage, the inflation rate and the growth rate of investments. To determine the trend in pulp prices for the Chinese market, we used official data from GDP growth forecasts. Highlighting the determinants of development and forecasting, taking into account the main factor of gross product, the trend-cyclical model of pulp prices allows us to anticipate natural deviations in market development, plan the cost of forest products, the cost of exporting forest materials, which is important for the financial situation of forestry enterprises. In general, the developed methodological approach is applicable to other types of forest products, and the results of the study can be used by enterprises, organizations of the forest complex when studying market conditions and planning activities for various periods. At the level of state bodies, forecast models allow planning the cost of export-import turnover of forest materials, production of products by forestry enterprises.
The role of special economic zones (SEZs) in achieving sustainable development in Nigeria
Authors: Alhassan Tijani Forgor , Stepannikova Oksana , Chebukhanova Lali
Published: August 2023

The development and implementation of Special Economic Zones (SEZs) has become one of the main directions of investment policies to many economies. The creation of SEZs is aimed at attracting foreign investment and boosting the entry of their manufacturers into the world market. This paper assesses the impact of SEZ programs on the sustainable development in Nigeria and define how SEZs contribute to employment and exports in selected sub-Saharan African countries. Furthermore, the effectiveness of certain types of financing in the main sectors and the level of their impact on sustainable development in Nigeria was analyzed. It was revealed that the mining sector financing methods do not seem to support or deliver on Nigeria's development goals, making it completely ineffective given the issues identified as well as the sector's contribution to improving the country's socio-economic performance. In other words, Nigeria should create various mechanisms and models for financing its manufacturing and agro-industrial complex through the creation of SEZs, as well as create the necessary preferential regimes in these sectors that can attract and direct huge investments in the manufacturing agricultural industries of these sectors. The authors developed a model for the relationship of investment with these indicators in African countries. A model was used to determine the degree to which job growth (p) and exports (e) are dependent on investment in special economic zones (SEZs). They conclude that the investment in SEZs is positively associated with job growth and exports.
Judicial fine as a means of ensuring sustainable state development
Authors: Podroykina Inna , Alekseeva Marina
Published: August 2023

The article states that sustainable development of the state requires a balanced policy, including criminalisation, decriminalisation of acts, penalisation, depenalisation as well as prosecution, non-criminalisation. That is why the authors targeted one of the types of exemption from criminal liability, the imposition of a court fine, which is relatively new and causes certain difficulties in its application in practise. The purpose of the study is to identify controversial provisions of the criminal law in relation to the regulation of court fines and, on the basis of this, to develop recommendations aimed at eliminating the identified deficiencies of the legislation. The work is based on such methods as system analysis, formal-legal, comparative-legal, statistical and concrete-sociological. Having examined in detail the conditions of exemption from criminal liability in connection with the imposition of a court fine, the authors draw attention to the fact that a number of points require specification, including the terms of payment of a court fine, the definition of its lower limit, etc. They also express their disagreement with the position of the Supreme Court which allows a broad interpretation of the law. Therefore, courts must find out the reasons for nonpayment of the court fines before cancelling the fine and bringing a person to criminal responsibility. On the whole, assessing positively the introduction of a rule allowing for exemption from criminal liability in connection with the imposition of a court fine, they conclude that only a deliberate use of this type of exemption from criminal liability will contribute to the sustainable development of the Russian state, which requires adjustment of the criminal law in terms of regulation of the court fine, as well as some positions of the Russian Supreme Court.
ESG audit and its fundamental concepts
Authors: Prodanova Natalia , Tarasova Olga , Sotnikova Lyudmila
Published: August 2023

According to the writers of the paper, ESG auditing is an innovative technique that is an important component in the chain of financial reporting for businesses. This strategy is founded on three pillars: environmental, social, and business risk management. The authors underline that ESG auditing is a business development tool that assists organizations in addressing environmental and social concerns as well as risk management. The article clarifies the reason why ESG auditing is essential, explores ESG audits as a way of enhancing businesses' capacity to function in compliance with emerging standards and requirements, and also diminish operational risks by managing issues.
Derivatographic analysis of bentonite "navbahor" in the technology of obtaining a nanocatalyst
Authors: Fayzullayev Normurot , Kurbonov Jamshed , Daminova Gulrukh , Saginaev Amanjan , Kurbanova Raxima , Kurbonov Jaxongir
Published: August 2023

This study presents an experimentally identified derivatogram of bentonite from the Navbahor mine, the texture of bentonite, physical and chemical characteristics, chemical composition, and their analysis of the retaining substance used in the preparation of nanocatalysts based on Zolgel technology.
Technology of producing local liquid parafines for separation of potassium chloride from natural sylvinite
Authors: Vakkasov S. S. , Mamadiyorova Sh. I. , Tadjieva G. A. , Gazikhodjayeva N. M.
Published: August 2023

The purpose of this study was to determine the possibility of obtaining liquid paraffins on the basis of by-products available in the local chemical industry, and to compare the product with industrial apolar wound agents in the process of silvinite flotation. The experiments were performed with a secondary liquid product - hexane solution and pyrocondensate. A technological sequence of reagent use to increase the efficiency of the flotation process is proposed. In order to increase the efficiency of the flotation process, the sequence of transfer of reagents to the process and the time of exposure were studied. Experiments have shown that adding 2.5 to 7.5% tetradecane and pentadecane to liquid paraffins derived from hexane used can reduce KCl residue by 2.2%. The technology producing of local liquid paraffins from hexane, a secondary product of Uz-Kor Gas Chemical JV LLC, has been developed.
Synthesis and characterization of europium (III), terbium (III) complexes and their mixture for making white light emission powder
Authors: Viet Dung Duong , Johar Masa , Khan Haziq Naseer , Segura-Ramírez Yutzil
Published: August 2023

The enhanced luminescence of lanthanide complexes coordinated to antenna ligands has potential applications for developing devices like screens and lamps. Herein, three β-diketone antenna ligands were incorporated into Eu(III) and Tb(III) metals to synthesize five complexes. Their luminescence properties in solid state and the energy levels of the electronic states for the ligands and the metals were recorded and probed by UV–vis and fluorescence spectroscopies. Under UV light, a white-light emission powder was observed by mixing red-emission europium and green-emission terbium complexes, with blue-emission laundry powder. The powder composition was tuned by using spectroscopic analysis and CIE 1931 color diagram.
Cardiopulmonary Bypass for Thoracic Aortic Aneurysm: A Report on 488 Cases
Authors: Guan Yulong , Yang Jing , Wan Caihong , He Meiling , Dong Peiqing
Published: August 2023

Our objective was to investigate different cardiopulmonary bypass (CPB) techniques for thoracic aortic aneurysm retrospectively. Four hundred and eighty-eight patients with thoracic aortic aneurysm received surgical treatment. Total CPB was used routinely in 331 cases with ascending aortic aneurysm. When the aneurysm expanded to the aortic arch, brain protection was executed by adopting deep hypothermia circulatory arrest (DHCA) or DHCA combined with retrograde cerebral perfusion (RCP). Selected cerebral perfusion via carotid artery was used in three cases and separated upper and lower body perfusion in five cases. Left heart bypass was adopted for the surgeries of 157 cases with descending aortic aneurysm. In two of the cases, ventricular defibrillation could not be achieved, and then bypass was altered to separated upper and lower body perfusion to acquire satisfactory outcome. In the ascending aortic aneurysm group, DHCA time in the 17 patients was 10–63 minutes (mean 35.58 ± 18.81 min), and DHCA ± RCP time in 61 patients was 16–81 minutes (mean 43.43 ± 17.91 min). Total mortality of aortic aneurysm surgery requiring full CPB was 5.4% (18/331), in which eight patients died in emergency operations. The total mortality of emergency operation was 11.9% (8/67). In the descending aortic aneurysm group, time of left heart bypass was 125.56 ± 57.28 min, and the total mortality was 7% (11 of 157 patients). Three patients developed postoperative paraplegia. Techniques for extracorporeal circulation for surgery of the aorta are dependent on the nature of the disease and require a flexible approach to meet the specific anatomical challenge. The ability to alter the perfusion circuit to meet unexpected situations should be anticipated and planned for. In this series, we have varied our approach to perfusion techniques as required with acceptable outcome data as compared to the international literature.
The In Vitro Effects of Aprotinin on Twelve Different ACT Tests
Authors: Jones Karen , Nasrallah Fadi , Darling Edward , Clay Nicole , Searles Bruce
Published: August 2023

Aprotinin is frequently used during CPB to reduce post-operative bleeding and attenuate the inflammatory response. The level of anticoagulation in these patients is monitored by using various activated clotting time (ACT) tests, which are generally accepted as being altered by the presence of aprotinin in blood. Therefore, we have investigated the effect of aprotinin on several ACT tests using whole blood from CPB patients.With IRB approval, blood samples were collected from patients undergoing CPB before and after full heparinization (300 u/kg). Each blood sample was divided into two aliquots, and aprotinin was added to one of them to yield a final calculated concentration of 300 KIU/mL. Both aliquots were used simultaneously to perform the 12 ACT tests. A paired Student’s t-test was performed on the data. Overall, test results from 9 of 12 devices were significantly increased by aprotinin. Of these, four were increased only when the sample was heparinized, three were elevated by both heparinized and unheparinized blood, and two were elevated only when the sample was unheparinized. Each affected test responded uniquely to aprotinin, producing ACT test results ranging from 12 to 51% above nonaprotinized values. Several tests that were affected by aprotinin using heparinized blood samples were unaffected using unheparinized blood samples. These data emphasizes the unique manner in which individual ACT tests respond to aprotinized blood samples and should be considered when developing institutional policy for anticoagulation of aprotinized patients.
A Rapid Platelet Function Assay Used to Regulate Platelet Transfusion Prophylaxis Following Cardiopulmonary Bypass Surgery
Authors: Shaffer Kathy E. , Pearman David T. , Galen Robert S. , Carville David G.M.
Published: August 2023

Subsequent to cardiac surgery with cardiopulmonary bypass (CPB), patients are at risk of postoperative bleeding caused by acquired defects associated with the procedure. As such, many patients receive prophylactic blood product transfusion. The effectiveness of measuring platelet function using a near-patient platelet function analyzer for the purpose of regulating platelet transfusion and potentially modulating other blood products including fresh frozen plasma (FFP) and cryoprecipitate (CRYO) transfusion was evaluated prospectively in patients undergoing CPB. A 6-month prospective study was designed that encompassed all CPB patients at Aultman Hospital (Canton, OH) during 2001. Each patient was assessed postoperatively for platelet count and function using a point-of-care analyzer. Data were used to help determine whether a platelet transfusion would be administered. Transfusion of CRYO and FFP was also recorded. The data were then compared to the retrospective same 6-month period in the preceding year for the purpose of determining the value of this system in guiding transfusion triage. There were 1770 platelet packs transfused during the study period, representing a 34% reduction in platelet usage. Platelet transfusions were reduced by 51% (5.75 in 2001 vs. 11.75 in 2000) per patient. CRYO/FFP usage was also substantially reduced. During the study period, the patient caseload had increased by 72 (310 vs. 238). Monitoring platelet count and function as a result of CPB and administering an appropriate transfusion protocol can positively impact transfusion outcome.
The Use of Cardiopulmonary Bypass and Extracorporeal Membrane Oxygenation for Support During Removal of Two Teratomas and Hydrops Fetalis
Authors: Burdis Leighann , Koch Donald D.
Published: August 2023

The removal of massive tissue tumors often leads to rapid blood loss and decreased lung compliance because of large volume shifts. Cardiopulmonary bypass (CPB) and extracorporeal membrane oxygenation (ECMO) have both been used as a means of support during resection of saccrococcygeal teratomas (1). Hydrops fetalis is the accumulation of fluid in extravascular spaces and body cavities. This leads to edema and sometimes hypoxia. ECMO has been used for support during treatment of hydrops fetalis (2). This patient was diagnosed, via sonogram, at 30 weeks gestation to have two teratomas and hydrops fetalis. Because of the risk of hemorrhage and poor lung compliance during removal of these types of tumors, CPB and ECMO were used. This support allowed for successful removal of the tumors. Following removal of the tumors, the patient failed to wean from CPB because of the severity of hydrops. The patient remained on extracorporeal support for treatment of hydrops fetalis. This report describes the perfusion techniques used for support during the removal of teratomas and the treatment of hydrops fetalis.
The Effects of Leukocyte Reduction on Matrix Metalloproteinase Release in Cardiopulmonary Bypass
Authors: Garner Jessica R. , Stroud Robert E. , Finklea Laura , Ikonomidis John S. , Dorman B. Hugh , Spinale Francis G.
Published: August 2023

Matrix metalloproteinases (MMPs) are a family of enzymes responsible for degrading the extracellular matrix, a process that likely contributes to the development of altered vascular permeability. Past studies in patients undergoing cardiopulmonary bypass (CPB) have documented increased levels of MMPs with CPB. The purpose of this study was to evaluate the effect of leukocyte reduction on MMP release during CPB. Patients (n = 17) undergoing elective coronary revascularization requiring CPB were randomly assigned to either a leukocyte-reducing filter (LRF) group (n = 9) or the standard CPB circuit with no LRF (n = 8). White blood cell (WBC) counts, MMP-2, and MMP-9 levels were serially measured at baseline and up to 12 hours post CPB. MMP levels were measured by enzyme-linked immunoassay. ProMMP-2 levels increased in both the non-LRF and LRF groups but to a higher degree in the LRF group. ProMMP-9 levels increased by 40% in the non-LRF group. In contrast, proMMP-9 decreased by 30% in the LRF group. The addition of leukocyte-reducing filters in the CPB circuit attenuated the release of MMP-9 but increased release of MMP-2 post-CPB. Because MMPs can degrade the extracellular matrix, leading to increased vascular permeability, attenuation of MMPs may have decreased the local tissue injury known to occur as a result of these enzymes. However, future prospective studies to test this hypothesis directly are warranted.
End-Tidal CO2 for Prediction of Cardiac Output Following Weaning from Cardiopulmonary Bypass
Authors: Baraka Anis S. , Aouad Marie T. , Jalbout Maya I. , Kaddoum Roland N. , Khatib Mohammad F. , Haroun-Bizri Sania T.
Published: August 2023

This prospective study included 32 patients undergoing cardiopulmonary bypass (CPB) for elective coronary artery bypass grafting correlates the respiratory end-tidal CO2 (ETCO2) during partial separation from CPB with cardiac output (CO) following weaning from CPB. After induction of general anesthesia, a pulmonary artery catheter was inserted for measurement of cardiac output by thermodilution. Patients were monitored using a 5-lead ECG, pulse oximeter, invasive blood pressure monitoring, rectal temperature probe, and end-tidal capnography. At the end of surgery, patients were weaned from CPB in a stepwise fashion. Respiratory ETCO2 and in-line venous oximetry were continuously monitored during weaning. The ETCO2 was recorded at quarter pump flow and after complete weaning from CPB. Following weaning from CPB, CO was measured by thermodilution. The CO values were correlated with the ETCO2 during partial bypass and following weaning from bypass. Regression analysis of ETCO2 at quarter-flow and post-bypass CO showed significant correlation (r = 0.57, p < .001). Also, regression analysis of ETCO2 after complete weaning from bypass and post-bypass CO showed significant correlation (r = 0.6, p = .002). The correlation between ETCO2 and CO showed that an ETCO2 >30 mm Hg during partial CPB will always predict an adequate CO following weaning from CPB. An ETCO2 <30 mm Hg may denote either a low or a normal cardiac output and hence other predictive parameters such as SvO2 must be added.
The Basic Science Aspect of Donor Heart Preservation: A Review
Authors: Rivard Andrew L. , Gallegos Robert P. , Bianco Richard W. , Liao Kenneth
Published: August 2023

In cardiac transplantation, the transport time between harvest and recipient is limited by the viability of the donor heart. The problem of viability is a consistent limitation in cardiac transplantation. Since the 1960s, techniques, including hypothermia, perfusion, oxygenation, and hyperbaria, have been used to prolong the preservation of the transplantable heart. Continuing development of cardioplegic solutions has minimized edema and oxygen radical formation, which have resulted in extension of the donor heart viability. New research into the events leading to necrosis, oncosis, and apoptosis may allow further advancement of protective cardioplegic solutions in combination with technology of transporting the heart. With a prolonged preservation time there is potential to increase the donor pool and ultimately improve post-operative outcomes.
A Technique for Performing Antegrade Selective Cerebral Perfusion Without Interruption of Forward Flow or Cannula Relocation for Pediatric Aortic Arch Reconstruction
Authors: Deptula Joseph J. , Fogg Sherrie K. , Glogowski Kimberly R. , Fenton Kathleen N. , Hunt Peter , Duncan Kim F.
Published: August 2023

New technology and advances in extracorporeal bypass circuitry and surgical techniques have drastically improved outcomes in infants with congenital heart defects. Hypothermia with circulatory arrest has fallen out of favor in many institutions over the last decade in part from data implicating even short circulatory arrest times to long-term neurologic sequelae. Implementing continuous cerebral perfusion techniques for aortic arch reconstruction is desirable in ameliorating neurologic complications because long-term survival of complex defects can be more routinely achieved. Many centers have implemented alternative means of alleviating cerebral ischemic periods by incorporating selective antegrade or retrograde cerebral perfusion techniques. The incidence of post-operative neurologic events is low when alternative cerebral perfusion techniques are used. Many techniques used to perform continuous cerebral perfusion involve brief periods of circulatory arrest, usually for perfusion cannula repositioning. Herein we describe a technique for performing continuous antegrade cerebral perfusion without a need to interrupt forward flow.
The Effectiveness of Low-Prime Cardiopulmonary Bypass Circuits at Removing Gaseous Emboli
Authors: Norman Matthew J. , Sistino Joseph J. , Acsell Jeffrey R.
Published: August 2023

During extracorporeal circulation, the patient’s blood is siphoned into the extracorporeal circuit (ECC) by gravity or may be assisted kinetically or by vacuum. In all instances, negative pressure is generated in the venous line, which can cause entrainment of air into the ECC at the cannulation site. The typical ECC uses a venous reservoir, membrane oxygenator, and arterial line filter, which together aid in removal of air that has entered the venous line and minimize the transmission of gaseous microemboli to the patient. Recently, several manufacturers have introduced low prime ECCs with component configurations that differ from conventional ECCs, including the omission of a venous reservoir. These configuration changes may change the ability of the circuit to handle air and therefore their ability to minimize gaseous microemboli. The purpose of this study was to test the ability of new low prime ECCs to remove air introduced into the venous line and minimize gaseous microemboli from entering the patient’s circulation. Using a model of CPB, air was introduced into the venous line of a low prime ECC and a conventional CPB circuit. The detection of the gaseous microemboli produced was monitored distal to the oxygenator by an ultrasonic emboli detector to determine if venous air was able to traverse the ECC at varying rates of air introduction and blood flow. Data was collected using data acquisition software loaded on a personal computer. Gaseous microemboli levels detected in the arterial line of the low prime ECC were 8 to 10 times higher than the microemboli levels detected in the conventional ECC at all blood flow rates. Every effort should be made to minimize and prevent air from being entrained in the venous line of a low prime CPB circuit to minimize the risk of arterial gaseous microemboli generation.
Anticoagulant Monitoring Techniques in a Heparin-Induced Thrombocytopenia Patient Undergoing Cardiopulmonary Bypass Using Bivalirudin Anticoagulant
Authors: Baker Trace , Chan Richard , Hill Fredrick
Published: August 2023

Heparin is widely used as the anticoagulant of choice for cardiopulmonary bypass. However, some patients exposed to heparin therapies develop heparin-induced thrombocytopenia (HIT). Severe complications of HIT-induced thrombosis may lead to end-organ dysfunction and death. Bivalirudin, a hirudin analog, is an alternative anticoagulant that may be used in the patient with HIT without inducing thrombotic disorders. This case report provides a look at the successful use of bivalirudin as the sole anticoagulant in a patient diagnosed with HIT undergoing minimally invasive cardiothoracic surgery requiring cardiopulmonary bypass for severe mitral insufficiency. An 80-year-old male presented to the operating room for a minimally invasive mitral valve repair. Past medical history included mitral valve prolapse, atrial fibrillation, hypertension, and congestive heart failure. Preoperative evaluation noted the existence of HIT with heparin exposure 2 months prior. The decision was made to use bivalirudin as the sole anticoagulant for the operative procedure. Anticoagulation evaluation was performed with both high-does thrombin time (HiTT) and Celite activated clotting time tubes for comparison using a Hemochron device. Cardiopulmonary bypass was initiated, and the patient’s mitral valve was repaired using a 34-mm annuloplasty ring. The patient was successfully weaned from bypass. No complications or evidence of HIT exacerbation were noted in the postoperative course.
Aprotinin and Hemostasis Monitoring Concerns During Cardiac Surgery
Authors: Swartz Michael F. , Fink Gregory W. , Searles Bruce
Published: August 2023

Aprotinin (Trasylol) is a serine protease inhibitor, isolated from bovine lung that initially was marketed for the treatment of pancreatitis. In the mid 1980s, reports of its ability to decrease hemorrhaging after cardiopulmonary bypass surgery introduced the drug to the realm of cardiac surgery. Unfortunately, its introduction into this arena was followed by the publication of multiple studies and case reports that blamed aprotinin for poor outcomes in the form of early graft closure. More than 17 years have passed since the initial article describing the use of aprotinin during cardiopulmonary bypass, and with time there has been a significant increase in scientific knowledge and clinical experience. Interestingly, modern literature does not support the dogma that aprotinin is a procoagulant. Aprotinin increases the activated partial thromboplastin time (aPTT), as well as the kaolin- and celite-activated clotting time (ACT), regardless of heparin. Aprotinin, because of its ability to inhibit kallikrein, has been found to decrease thrombin antithrombin III complexes, fibrin-split products, fibrinopeptide1+2, prothrombin fragments, and all markers of thrombin formation. Some authors have suggested that it may have a synergistic effect with heparin to ensure graft patency. Anticoagulation monitoring during the use of aprotinin also has been developed based on early studies. Aprotinin administration does influence the results of various ACT tests, and consequently different methods of testing anticoagulation have been developed. Researchers have demonstrated that the celite ACT is not “artificially” prolonged in the presence of heparin and aprotinin, rather the kaolin ACT is “artificially” shortened. This article will review the scientific literature with regard to aprotinin’s anticoagulatory effects and review the current recommendations for hemostasis monitoring during the use of aprotinin.
Aprotinin Dosing: How Much Is Enough?
Authors: Niimi Kevin S.
Published: August 2023

Coagulopathy and postoperative bleeding continue to be a major concern for patients undergoing cardiac surgery with cardiopulmonary bypass. Pharmacologic attenuation of this morbidity has been one area that clinicians have held in high interest. Aprotinin, a serine protease inhibitor, has been shown to be effective in reducing bleeding as well as the need for blood component transfusions. Although effective, aprotinin is an expensive drug and this, in conjunction with a cost-conscious community, has led clinicians to determine what is the lowest effective dose of aprotinin. From these studies, various aprotinin dosing regimens have been studied with differing results. The purpose of this work is to review the effectiveness of the various dosing strategies and to examine potential benefits of a dosing regimen based on a patient’s weight, which may allow clinicians to achieve the maximal benefits from aprotinin without overdosing patients.
Numerical analysis of finite element methods for the cardiac extracellular-membrane-intracellular model: Steklov–Poincaré operator and spatial error estimates
Authors: Fokoué Diane , Bourgault Yves
Published: August 2023

The extracellular-membrane-intracellular (EMI) model consists in a set of Poisson equations in two adjacent domains, coupled on interfaces with nonlinear transmission conditions involving a system of ODEs. The unusual coupling of PDEs and ODEs on the boundary makes the EMI models challenging to solve numerically. In this paper, we reformulate the problem on the interface using a Steklov–Poincaré operator. We then discretize the model in space using a finite element method (FEM). We prove the existence of a semi-discrete solution using a reformulation as an ODE system on the interface. We derive stability and error estimates for the FEM. Finally, we propose a manufactured solution and use it to perform numerical tests. The order of convergence of the numerical method agrees with what is expected on the basis of the theoretical analysis of the convergence.
Governance of Electronic Health Record Modification at U.S. Academic Medical Centers
Authors: Ravi Akshay , Arvisais-Anhalt Simone , Weia Benjamin , Khanna Raman , Adler-Milstein Julia , Auerbach Andrew
Published: August 2023

Objectives A key aspect of electronic health record (EHR) governance involves the approach to EHR modification. We report a descriptive study to characterize EHR governance at academic medical centers (AMCs) across the United States.

Methods We conducted interviews with the Chief Medical Information Officers of 18 AMCs about the process of EHR modification for standard requests. Recordings of the interviews were analyzed to identify categories within prespecified domains. Responses were then assigned to categories for each domain.

Results At our AMCs, EHR requests were governed variably, with a similar number of sites using quantitative scoring systems (7, 38.9%), qualitative systems (5, 27.8%), or no scoring system (6, 33.3%). Two (11%) organizations formally review all requests for their impact on health equity. Although 14 (78%) organizations have trained physician builders/architects, their primary role was not for EHR build. Most commonly reported governance challenges included request volume (11, 61%), integrating diverse clinician input (3, 17%), and stakeholder buy-in (3, 17%). The slowest step in the process was clarifying end user requests (14, 78%). Few leaders had identified metrics for the success of EHR governance.

Conclusion Governance approaches for managing EHR modification at AMCs are highly variable, which suggests ongoing efforts to balance EHR standardization and maintenance burden, while dealing with a high volume of requests. Developing metrics to capture the performance of governance and quantify problems may be a key step in identifying best practices.
DMSO arbitrated Oxidative Annulation Followed by Homologated N-Alkylation: Microwave-Assisted Efficient and Greener Approach to Access 3-(3-Oxo-3-arylpropyl) Quinazolinones
Authors: Babu Bathini Nagendra , Prasanthi A. V. G.
Published: August 2023

A convenient, time efficient, tandem approach for the synthesis of medicinally privileged 3-(3-oxo-3-arylpropyl) quinazolinones is developed from ubiquitously available acetophenones and anthranilamide via microwave irradiation. This transition-metal-free reaction is initiated by the oxidative annulation of anthranilamide and in situ generation of α,β-unsaturated carbonyl compounds from aryl ketones in the presence of K2S2O8 and dimethyl sulfoxide. The latter acts as a source of two carbons [methine (=CH–) and methylene (–CH2–)] apart from being the solvent. The reaction is carried out under microwave irradiation which has the advantage of homogenous heat distribution, reducing the reaction time drastically compared to the conventional heating reaction.
Role of Aprotinin in Moderate and Severe Burns
Authors: Bhatnagar Prateek , Singh A. K. , Tarachand Tarachand
Published: August 2023

The role of Aprotinin (Antagosan) in moderate and severe thermal burns has been studied. Patients were randomized in two groups; both receiving same treatment with the exception that patients in trial group received Aprotinin in addition. 2000,000 K.I.U. (Kallikrein inhibition units) Aprotinin was given I.V. stat, followed six hourly, for three days. Mortality was 27.08 percent in trial group and 47.9 percent in control group (p < 0.05). Aprotinin is believed to be helpful in reducing mortality in burns.
Immunogobulins and Thermal Burns Infections
Authors: Mehdiratta N. K. , Singh H. P.
Published: August 2023

Burns patients have higher susceptibility to infections, causes of which are many fold. Leakage of immunoglobulins in blister fluid is one of them. The present work was undertaken to find out the relationship between the types of infections and the levels of various immunoglobulins in the sera of burn patients. Radial immunodiffusion technique of Mancini was utilized to measure the levels. It was observed that all types of infections produced rise in immunoglobulin levels. In mixed and Pseudomonas infections the rise of all major immunoglobulins was found statistically insignificant while in fungally invaded patients IgM levels were significantly raised but on excision of the invaded areas, IgM levels dropped to within normal range.
Extended Medial Gastrocnemius Myocutaneous Flap (A Case Report)
Authors: Saha Ila , Sinha P. , Banerjee A. K.
Published: August 2023

The extended gastrocnemius myocutaneous flap is a good technique for reconstruction of skin and soft tissue loss of the lower third leg defects. We have obtained satisfactory result in our case by using this flap.
Reconstitution of the Oral Sphincter
Authors: Chowdhury Siti Royh
Published: August 2023

The result in a fourteen year old female child with macroglossia and lax oral sphincter who was treated successfully by glossectomy and free palmaris longus muscle grafts for reconstituting the oral sphincter is being presented.
The Dorso-Lateral Flap in Post Burn Flexion Contracture of Fingers
Authors: Singh A. K. , Kalra G. S. , Pandey S. D.
Published: August 2023

Volar defects of the fingers can be resurfaced by a flap from the dorso-radial or dorso-ulnar aspect of the same finger. Its use following release of twenty-one post burn flexion contracture of the fingers in fifteen patients has been discussed.
Goldenhar's Syndrome (A Case Report)
Authors: Bhattacharya S. , Bhatnagar S. K. , Chandra R.
Published: August 2023

Goldenhar's syndrome or occulo-auriculo-vertebral dysplasia is characterized by the presence of abnormalities of the first and second branchial arches accompanied by apibulbar dermoids or lipodermoids and vertebral anomaties. Other associated congenital anomaties may be frequently present. A case of Goldenhar's syndrome with macrostomia, transverse facial cleft and telepes calcaneovalgus deformity is being presented.
Examining Chinese social sciences graduate students’ understanding of research ethics: implications for their research ethics education
Authors: Huang Jinyan , Wang Yuehan
Published: August 2023

Using the research ethics scale (Huang et al., 2021) and follow-up interviews, this study examined Chinese social sciences graduate students’ understanding of research ethics of empirical studies involving human subjects. The participants included 463 Chinese graduate students majoring in teacher education, English education, management, and economics. The quantitative findings suggested that these graduate students had a fairly good understanding of researchers’ ethical responsibilities and developed general human subjects’ ethical awareness; furthermore, there existed significant research experience and gender-by-research experience interaction effects on their understanding of researchers’ ethical responsibilities and human subjects’ ethical awareness, respectively. The qualitative results indicated that the participants had realized the importance of ethics reviews for social sciences research including human subjects; and they identified best ways to promote research ethics education for social sciences graduate students in Chinese higher education. Implications for Chinese university leaders, program developers, and research methods professors are discussed.
Modeling the reuse intention and practices of secondhand clothing: evidence from a developing nation
Authors: Wu Mengling , Al Mamun Abdullah , Yang Qing , Masud Muhammad Mehedi
Published: August 2023

This study explored the effect of perceived values on sustainability, problem awareness, the ascription of responsibility, sense of community, and anticipated guilt on reuse (sell and/or swap) intention of secondhand clothing through partial least squares structural equation modeling. This study adopted a cross-sectional design and collected quantitative data from 524 conveniently selected respondents in China through an online survey. The findings revealed that perceived values on sustainability, ascription of responsibility, sense of community, and anticipated guilt are the most important factors influencing reuse intention, whereas problem awareness is not a significant predictor. It has also been demonstrated that reuse intention promotes the development of reuse practices. Despite its large population, China is facing significant environmental challenges. The findings of this study may provide a viable option for the sustainable development of reusing secondhand clothing and also contribute to new knowledge on the factors that influence the reuse practices of secondhand clothing in China and even around the world.