bluuebunny/crossref_metadata_2025 huggingface dataset:
Development and Experimental Testing of Connections for the Simple for Dead Load--Continuous for Live Load Steel Bridge System
Authors: Lampe Nick , Mossahebi Nazanin , Yakel Aaron , Farimani Reza , Azizinamini Atrod
Published: April 2024

The most critical aspect of the simple for dead load and continuous for live load (SDCL) bridge system is identifying a detail capable of connecting the girders over the interior supports. An experimental program was set up to identify and study the fundamental characteristics of an interior connection for the SDCL bridge system. Three full-scale test specimens were constructed and tested, each using different connection details for possible use in the SDCL bridge system. Each specimen was subjected to two types of loading: cyclic testing to simulate long term truck traffic loads, and an ultimate load test to determine the ultimate capacity of the system. Results of the tests indicated that connection details meeting the design provisions could consist of embedding the girder ends in the concrete diaphragm and would provide a good service life. The main objective in using a concrete diaphragm to join the girder ends over the interior support is to prevent crushing of the concrete adjacent to the compression flanges of the girder and embedded in the concrete diaphragm. One of the primary conclusions is that deck reinforcement is sufficient to develop continuity, and the top flange need not be continuous over the interior support.
Simple for Dead Load--Continuous for Live Load Steel Bridge Systems
Authors: Azizinamini Atorod
Published: April 2024

This paper presents the development of design, fabrication, erection and construction procedures for a new steel bridge system referred to as simple for dead and continuous for live loads (SDCL). The economy of the SDCL system depends on several factors, including the use of economical and efficient details over the interior supports. Extensive experimental, numerical and analytical work was conducted to develop economical details and efficient ways of using the SDCL steel bridge system for straight and minimally skewed bridges in which the skew angle is less than 10Â°. Several bridges were then designed using the research results and their performance from the time of fabrication to construction and their long term behavior were studied. This knowledge was then used to provide detailed information on design, fabrication, erection, and construction procedures for steel bridges using the SDCL system. This paper provides a summary of the entire work, including design recommendations and economical details to be employed in conjunction with the SDCL steel bridge system.
A Graphical Design Aid for Selecting Standard W-Shape Steel Beam-Columns with Minimum Weight
Authors: Saadat Mohammad Ali , Banan Mohammad Reza
Published: April 2024

This paper presents an alternative technique for selecting the lightest W-section for beam-column members. Following the AISC procedure, the number of required steps to find a feasible section highly depends on the initial trial section. A new graphical technique based on the AISC interaction formula for designing steel beam-columns is proposed. By employing the newly developed diagrams, the new approach quickly leads to the lightest feasible section for a member subjected to combined biaxial bending and axial force. The number of computational steps in the proposed method is slightly reduced from the current AISC procedure. Some advantages of the new proposed method are converging to the solution in fewer steps, imposing no limit on Lb, considering the effect of Cb, considering biaxial bending by simply using a modification factor and covering cases where Lb is not equal to KL.
Weld Effective Lengths for Rectangular HSS Overlapped K-Connections
Authors: Tousignant Kyle , Packer Jeffrey A.
Published: April 2024

One large-scale, 33-ft-span, simply supported, Warren truss was tested to assess the performance of welds in rectangular hollow structural section (HSS) overlapped K-connections. Nine overlapped connections, within the truss, were designed to be weld-critical and sequentially failed by producing an axial force distribution with a point load, applied quasi-statically, to strategic panel points. The structural reliability (or safety index) of the existing AISC specification formulas for the effective length of welds in rectangular HSS overlapped K-connections, in Table K4.1 of the 2010 AISC Specification for Structural Steel Buildings, was determined from the tests. The results indicate that these provisions are conservative; hence, a modification to the current requirements that limits the effective width of the transverse weld elements is proposed. The proposal establishes a more economical and yet still safe weld design method for rectangular HSS overlapped K-connections.
Steel Structures Research Update: Steel-Concrete Composite Beams at Ambient and Elevated Temperatures
Authors: Liu Judy
Published: April 2024

Ongoing and recently completed research on steel-concrete composite beams and floor systems at ambient and elevated temperatures is presented. The research highlighted here includes investigations into shear connector slip, composite beams with high-strength steel, and tests of real-scale composite floor systems subjected to fire and structural loading.
Buckling of Conventional and High-Strength Vanadium Steel Double-Angle Compression Members: Computational Parametric Study
Authors: Webster Mark D. , Citipitioglu Ahmet , Mayes Ronald L. , Talaat Mohamed M. , Kan Frank W.
Published: April 2024

High-strength, low-alloy vanadium (HSLA-V) steel offers higher strength and toughness than conventional steel. The resulting lighter weight and more slender structural components are more susceptible to buckling in compression. A series of conventional Grade 50 steel and HSLA-V (nominal Grade 80) steel angle compression components was tested at Lehigh University’s ATLSS laboratory. This experimental database was used to develop and verify a modeling approach using the general purpose finite element (FE) software ABAQUS to simulate the component buckling response. This study extensively evaluates the 2010 American Institute of Steel Construction (AISC) and Steel Joist Institute (SJI) design equations for double-angle buckling, resulting in significant findings and recommendations for both specifications. The primary objective of this paper was to assess the validity of applying the buckling equations given in the SJI 2010 Design Specification for long-span and deep-long-span joists (SJI, 2010) to double-angle compression members manufactured using 80-ksi HSLA-V steel. Present SJI specifications are applicable only for steel with specified yield stress of 50 ksi or less. Another objective of this study was to compare the design equations for compression buckling in the SJI Design Specification and the AISC 2010 Specification (AISC, 2010) and to develop recommendations for enhancing the accuracy of buckling equations commonly used in current practice. To achieve these goals, an extensive database of analytical buckling simulations was created to compare the performance of the code buckling equations in determining the buckling strength for regular and HSLA-V steel compression members. Potential solutions for resolving the observed lack of conservatism in the strong-axis buckling predictions were investigated. The use of the modified component slenderness ratio in the AISC provisions significantly improved the accuracy of the SJI buckling strength predictions for strong-axis buckling cases with Q-factor values less than 1.0.
Complementary Evaluation of Diagonal Tension Field Inclination Angle in Steel Plate Shear Walls
Authors: Fu Yushan , Bruneau Michel
Published: April 2024

Complementarily to previous studies, research was conducted to investigate whether the equivalent constant angle of diagonal tension field action should be taken as either 40° or 45° for ductile steel plate shear walls (SPSW) designed per current codes. A two-dimensional finite element (FE) model was first calibrated against results from a prior study of “limited-ductility SPSW” by comparing effective stress contours and average angle of diagonal tension field action at different locations across the web plate. Then, this SPSW was redesigned as a ductile SPSW in compliance with the 2016 AISC Seismic Provisions (AISC, 2016a) to have fully restrained beam-to-column connections and analyzed using strip models and finite element models, respectively. The AISC moment-axial force interaction equation was used to compare demands in the SPSW boundary elements obtained from the strip and finite element models. With respect to the use of a single angle in design, it is shown that using an inclination angle of 45° is slightly (but not significantly) more conservative than using 40° as far as boundary element design is concerned. On the basis of these observations, along with findings from previous research on the diagonal tension field inclination angle, it is recommended that a single constant angle of either 40°or 45° be used for the design of SPSW.
Guidance on Shear Rupture, Ductility and Element Capacity in Welded Connections
Authors: Fortney Patrick J. , Muir Larry S. , Thornton William A.
Published: April 2024

Several considerations need to be made while in the process of designing welds and welded connections. For the most part, the AISC Specification for Structural Steel Buildings, in combination with corresponding parts of the AISC Steel Construction Manual, provides fairly good guidance on what is required to design Specification-compliant welds. However, there seems to be some confusion and controversy in regard to a few of these considerations. Specifically: (1) when is the load path from the weld to the connecting element(s) unclear? (2) When should the ductility factor be applied to a weld? (3) When should a weld be sized to develop the strength of a connecting plate? This paper is written in an effort to provide guidance in regard to these three considerations. Background into the development of the equations used to make these checks along with some discussion on the intent of application is provided and supported with some anecdotal examples. It is the objective of the authors to shed some light on these issues and hopefully clear any confusion and/or controversy, as well as to encourage more consistency throughout the steel construction industry with regard to these three considerations.
Simplified Equations for Shear Strength of Composite Concrete-Filled Steel Tubes
Authors: Kenarangi Hadi , Bruneau Michel , Varma Amit H. , Ahmad Mubashshir
Published: April 2024

Shear strength of filled composite members, namely, circular or rectangular concrete-filled steel tubes (CFST) have been investigated in past research. Results established the relative contributions of the steel tube and concrete infill to the total shear strength and showed that the concrete contribution depends on the development of a compression strut in the concrete infill when shear-span values are low. While experimental results and numerical models are available in the literature, simple equations that empirically encompass this behavior are preferable for design purposes. This paper provides an overview of the technical approach that has been followed to propose such equations for consideration and possible implementation in future editions of design specifications. The shear strength obtained using the proposed equation is compared with the shear test database from the existing literature and found to be safe; it accurately captures the contribution of the steel tube to the total shear strength and conservatively approximates that of the concrete.
Interaction Strength of Steel-Concrete Composite Beam-Columns Including the Balance Point
Authors: Denavit Mark D.
Published: April 2024

The maximum bending moment capacity of steel-concrete composite column cross sections occurs with concurrently applied axial compression. This is seen in the shape of the interaction diagram, where the bending moment capacity increases with increasing axial compression before reaching the balance point. The size of this bulged region of the interaction diagram can be significant, especially for concrete-dominant sections. However, it is often neglected in design because of two stability-related concerns. First, the simple transformations that are recommended to convert cross-section strength to member strength produce illogical results near the balance point, with member strength exceeding cross-section strength. Second, research has shown that the stiffness reductions used in elastic analyses are not sufficient for highly slender concrete-dominant composite members subjected to high bending moments. This work seeks to address these issues through the development of more advanced transformations and stiffness reductions. These new recommendations will more accurately capture the strength of composite members and allow for more efficient designs.
Errata: The Severity of Fires in Steel-Frame Buildings
Authors: L.G. Seigel
Published: April 2024

Errata
Shear Strength of Thin Flange Composite Specimens
Authors: Goble George G.
Published: April 2024

Light gage steel is finding increasing use in load-carrying elements of structural systems. If very thin steel sections are to be used extensively in composite construction, experimental data on the behavior of the shear connector system are necessary. The purpose of this study was to explore the behavior of stud shear connector composite pushout specimens. Previous experimental studies of this composite system have been concerned with determining the behavior of the specimen when failure occurs either by pulling-out of the shear connector from the concrete or byshearing of the connector. If very thin steel flanges are used, it must be expected that failure could be controlled by pullout of the connector from the steel flange. The tests reported here examined the behavior of thin flange push-out specimens with 0.5, and 0.75 in. diameter welded stud shear connectors. The line defining the shift in failure mode from stud shear to flange pull-out is located.
Experimental Evaluation on Lateral Torsional Buckling Resistance of Continuous Steel Stringers
Authors: Sun C .Shawn , Linzell Daniel G. , Puckett Jay A. , Rageh Ahmed
Published: April 2024

An extensive experimental study evaluated lateral torsional buckling resistance of two-span, continuous, steel beams in a test assembly that included three beam lines, an interior transverse support (floor beam), and transverse diaphragms at the end supports. Funded by the Louisiana Transportation Research Center (LTRC), this study was conducted to better understand continuous stringer behavior so that simplified analyses would better capture their lateral torsional buckling (LTB) behavior. Current practice produces Louisiana Department of Transportation and Development (LA DOTD) bridge ratings often conservatively controlled by stringer LTB capacity and, in many cases, necessitates posting; thereby imposing significant and often unnecessary operational restrictions. Forty-seven elastic tests were completed. The tests encompassed a variety of unbraced lengths and support conditions with steel diaphragms or timber ties acting as bracing members. The interior beam in the test assembly was loaded orthogonal to its strong axis at the middle of one or both spans using a spreader beam that minimized restraint and prevented the development of follower forces. Tests demonstrated that minimal bracing could significantly increase lateral torsional buckling resistance and justify a higher LTB resistance than what is currently used. Although the tests were conducted on assemblies used to represent a bridge floor system, the results provided an extensive set of valuable data that could be used by structural steel researchers interested in examining flexural resistance of continuous beams.
Reliability in Building Construction Through Nondestructive Testing
Authors: Greenberg Simon A.
Published: April 2024

Before World War II, structural welding was used only by a few pioneer-spirited designers. Then they had difficulty finding fabrication shops that were willing and able to acceptwelded work of any magnitude. At the same time, welding was used for making repairs and for strengthening existing structures under conditions that would be considered less than desirable even today. Yet this was not considered a contradiction. There was no other way to make these repairsor renovations—so welding had to be used. Structural welding almost ceased during World War II. Emphasis was on producing war material—ships, tanks, machinery, some portable building frames, and the like. Designers and fabricators of buildings had to turn from their usual work to war production. Time was the critical factor in this work. Any design, material, or process that would resultin getting the work done sooner was employed. Here was an opportunity to prove the advantages of welding. Savings in material, dead weight, and production time were realized through welding. Mistakes were made, but through them people were educated. The concept of weldability was developed. Thousands of welders were trained under goverment programs. With the end of the war, building designers and fabricators were ready and eager to use welding. Their wartime experience could now be used advantageously for their more usual pursuits. Fabrication shops had new and efficient welding equipment. Much of the riveting equipment was old and worn. An ample supply of trained welders could be drawn from. As expected, the day of structural welding had arrived.
Analysis of Helicoidal Girders
Authors: Abdul-Baki Assad , Bartel Dean
Published: April 2024

Helicoidal girders are becoming very common structural members in staircases, bridges, and ramps. Their structural analysis is cumbersome and difficult, and is often simplified from the case of a curved space girder to the case of a circular bowed girder. A few investigators have done some work on this problem, covering some special cases. The purpose of this study is not only to present an analytical method of analysis, but also to provide the designer with a set of design charts from which he can determine directly the redundants of a fixed-ended helicoidal girder of any given symmetrical cross section, slope, and curvature. In spite of the fact that these charts are limited to the case of a uniformly distributed load, they cover a multitude of cases that include a wide range of geometrical configurations.
One Engineers Opinion (Rectangular Section Beams)
Authors: Milek Jr. William A.
Published: April 2024

One Engineers Opinion
Temperature Effects on Tall Steel Framed Buildings Part 2-Structural Analysis
Authors: West Harry H. , Kar Anil K.
Published: April 2024

Recent trends in architectural design have led to the construction of multistory structures with the exterior columns partially or fully exposed. Such an arrangement provides a pleasing aesthetic effect with strong vertical lines. However, this arrangement subjects the exposed columns to severe temperature variations, whereas the interior columns remain in a controlled environment. These variations induce changes of length of the exterior columns which induce forces throughout the structure. The magnitude of these forces depends on many things, but of primary importance is the height of the structure. For low structures, the effects are small; however, for tall buildings they may be significant. The response of structural members to temperature variations is well known, but little work has been done on the analysis and design of tall steel buildings in which temperature changes occur in the exposed columns. Khan and Fintel developed a procedure for the analysis of temperature effects in reinforced concrete structures. Their procedure is an approximate iteration process which assumes rigid beam-to- column connections. This assumption is valid for reinforced concrete structures; however, steel structures may have rigid or semi-rigid connections. There are several schemes of complete structural analysis available to the designer that can be used for the temperature problem. The Structural Design Language (STRUDL) of Integrated Civil Engineering System (ICES) is an example of such a scheme. This problem-oriented program provides a stiffness method of analysis for the complete frame. However, at present, semi-rigid joints and complicated temperature gradients cannot be handled. STRUDL is used for comparison in this study; however, the cost prohibits its use for the parameter study.
Temperature Effects on Tall Steel Framed Buildings Part 1-Response of Steel Columns to Temperature Exposure
Authors: McLaughlin E.R.
Published: April 2024

In tall buildings the steel frame is usually inside the curtain wall line, so that the columns are protected from the temperature fluctuations of the weather (Fig. 1a). In this constant temperature position the length of the column remains constant and stresses due to temperature change are avoided. Many new designs place the columns on the wall line, where they are subjected to temperature variations which are a portion of the variations in the weather air temperature. The American Iron and Steel Institute sponsored research to determine the response of columns to changes in air temperature and what effects these responses might have on dimensions and stresses. A standard 14-in. wide flange section weighing 228 lbs per ft was selected for two columns to be exposed simultaneously. Three column locations were used to simulate the face-exposed, semi-exposed, and fully exposed locations of the column in the wall. In the first instance, only the outside flange extended beyond the wall line. In the second case, the wall line intersected the neutral axis of the column. In the fully exposed position, the entire web of the column was beyond the wall line. The bare or uncovered columns were observed, as well as columns with covers and various arrangements of insulation and fireproofing. Temperatures were observed at numerous locations on the column, after equilibrium had been attained with a warm-side air temperature of approximately 75°F and cold-side air temperatures of 20°, 0° and —20°F.
Discussion: Design of Steel Bearing Plates
Authors: Gogate Anand B. , Fling Russel S.
Published: April 2024

Discussion
Treatment of Eccentrically-loaded Connections in the AISC Manual
Authors: Higgins T.R.
Published: April 2024

As in earlier editions, the recommended loads for eccentrically loaded connections and the coefficients tabulated in the AISC Manual of Steel Construction, 7th Edition, for their design are more conservative than might be expected in view of recent studies and tests. (See the paper by Carl L. Shermer in this issue of the Engineering Journal.) However, there are a number of factors—including the need for further research into the plastic behavior of large connections subject to considerable eccentricity of loading— which discouraged across-the-board adaptation of these findings during preparation of the 7th Edition of the Manual. Unfortunately, calculation of the plastic strength of eccentrically loaded fastener patterns requiring the determination, by an iterative procedure, of the center of rotation satisfying the three equations of equilibrium would be far too tedious using ordinary slide-rule methods. Therefore, resort to the familiar vector method of analysis, even at the sacrifice of some economy in fabrication cost, would still be justified in evaluating unusual fastener patterns.
Plastic Behavior of Eccentrically-Loaded Connections
Authors: Shermer Carl L.
Published: April 2024

Structural connections are generally designed on the basis of their ultimate strengths. This has always been so, even though design methods might seem to suggest that stress is the criterion. However, there are probably very few connections of any kind in which stresses at some location have not reached the yield point during construction or under design loads. As a matter of fact, if connection material were not ductile and could not yield, connections and their method of design would have to be completely revised. Present "elastic" design methods work because ductile behavior is assumed implicitly and design stresses are based upon the distribution of stress when local yielding occurs. For example, centrally-loaded connections are assumed to be stressed uniformly throughout the joint but distribution at working loads is not uniform even in the simplest of connections. For that matter, in a single rivet or bolt or in a single spot of weld there are steep stressgradients and stress concentrations. In addition, there is a great variation between individual fasteners or between different areas in the same weld. When the connection begins to yield, however, the stresses become quite uniform. "Elastic" analysis has been used as the basis for design because it involves reasonably simple calculations which lead to safe designs, even though it is known that the results in many cases are more conservative than necessary and that the calculated stresses are not representative of the actual stresses by a wide margin.
Discussion: Plastic Behavior of Eccentrically-Loaded Connections
Authors: Kulak G.L. , Shermer Carl L.
Published: April 2024

Discussion
The Case for the Semi-Box Girder
Authors: Schlenker Norman E.
Published: April 2024

The semi-box girder is that breed having a partly open and a partly closed cross section. As such, it is not as torsionally stiff as a rectangular box girder, but substantially stiffer in this regard than an open section. Its main attribute is its ability to resist failure by lateral torsional buckling and, as such, is useful in bridge work to facilitate erection, or in other instances when the girder is used in an isolated condition, such as in a monorail or crane girder. This type of girder certainly did not originate with the author; it has been reported upon at least twice previously. Homer M. Hadley reported on the "Delta Girder" at the same time that Edward Luss reported on the "Double Y Girder" on the following pages of the same reference. The cross-sectional designs are illustrated in Fig. 1. In both instances (delta and double Y girders), the applications were in highway bridges, where the torsional strength lent itself to easy and safe erection, while the cross section, by bracing the web, eliminated stiffeners. The result was a simple and clean section, easy to look at and easy to maintain. In another article, Mr. Hadley provided details of construction and photographs of certain bridges both during construction and following completion, in which he not only emphasized the above attributes, but also pointed out the additional advantages of a shorter effective roadway slab span and better bonding of the slab to the girder top.
Dermatological aspects of primary psychiatric disorders
Authors:   University of Debrecen, Faculty of General Medicine, Institute of Behavioral Sciences, Debrecen, Halász Katinka , Remenyik Éva , Fekete Zita
Published: April 2024

The field of psychodermatology has received increasing attention because psychological comorbidity associated with skin lesions impairs our patients' quality of life, compliance with dermatological treatment and its success. In our review, possible classifications of comorbid psychological disorders of high dermatological significance are presented . Furthermore primary psychiatric disorders of relevance to dermatological practice are demonstrated. We describe their clinical picture, epidemiology and comorbidities.. Lesions that can be identified as alarming signs are highlighted, This will be carried out along the DSM-5 nosological system, with the alphanumeric codes of ICD-10.
LPS-induced systemic inflammation is suppressed by the PDZ motif peptide of ZO-1 via regulation of macrophage M1/M2 polarization
Authors: Lee Hyun-Chae , Park Sun-Hee , Jeong Hye Min , Shin Goeun , Lim Sung In , Kim Jeongtae , Shim Jaewon , Park Yeong-Min , Song Kyoung Seob
Published: April 2024

The gram-negative bacterium lipopolysaccharide (LPS) is frequently administered to generate models of systemic inflammation. However, there are several side effects and no effective treatment for LPS-induced systemic inflammation. PEGylated PDZ peptide based on zonula occludens-1 (ZO-1) was analyzed for its effects on systemic inflammation induced by LPS. PDZ peptide administration led to the restoration of tissue injuries (kidney, liver, and lung) and prevented alterations in biochemical plasma markers. The production of pro-inflammatory cytokines was significantly decreased in the plasma and lung BALF in the PDZ-administered mice. Flow cytometry analysis revealed the PDZ peptide significantly inhibited inflammation, mainly by decreasing the population of M1 macrophages, and neutrophils (immature and mature), and increasing M2 macrophages. Using RNA sequencing analysis, the expression levels of the NF-κB-related proteins were lower in PDZ-treated cells than in LPS-treated cells. In addition, wild-type PDZ peptide significantly increased mitochondrial membrane integrity and decreased LPS-induced mitochondria fission. Interestingly, PDZ peptide dramatically could reduce LPS-induced NF-κB signaling, ROS production, and the expression of M1 macrophage marker proteins, but increased the expression of M2 macrophage marker proteins. These results indicated that PEGylated PDZ peptide inhibits LPS-induced systemic inflammation, reducing tissue injuries and reestablishing homeostasis, and may be a therapeutic candidate against systemic inflammation.
A Modified BPaL Regimen for Tuberculosis Treatment replaces Linezolid with Inhaled Spectinamides
Authors: Ali Malik Zohaib , Dutt Taru S. , MacNeill Amy , Walz Amanda , Patterson Johnathan , Pearce Camron , Lam Ha , Henao-Tamayo Marcela , Lee Richard E. , Liu Jiuyu , Robertson Gregory T. , Hickey Anthony J. , Meibohm Bernd , Gonzalez-Juarrero Mercedes
Published: April 2024

The Nix-TB clinical trial evaluated a new 6-month regimen containing three-oral-drugs; bedaquiline (B), pretomanid (Pa) and linezolid (L) (BPaL regimen) for treatment of tuberculosis (TB). This regimen achieved remarkable results as almost 90% of the multidrug resistant (MDR) or extensively drug resistant (XDR) TB participants were cured but many patients also developed severe adverse effects (AEs). The AEs were associated with the long-term administration of the protein synthesis inhibitor linezolid. Spectinamide 1599 (S) is also a protein synthesis inhibitor of Mycobacterium tuberculosis with an excellent safety profile but which lacks oral bioavailability. Here we hypothesize that inhaled spectinamide 1599, combined with BPa ––BPaS regimen––has similar efficacy to that of BPaL regimen while simultaneously avoiding the L-associated AEs. The BPaL and BPaS regimens were compared in the Balb/c and C3HeB/FeJ murine chronic TB efficacy models. After 4-weeks of treatment, both regimens promoted equivalent bactericidal effect in both TB murine models. However, treatment with BPaL resulted in significant weight loss and the complete blood count suggested development of anemia. These effects were not similarly observed in mice treated with BPaS. BPaL treatment also decreased myeloid to erythroid ratio and increased concentration of proinflammatory cytokines in bone marrow compared to mice receiving BPaS regimen. During therapy both regimens improved the lung lesion burden, reduced neutrophil and cytotoxic T cells counts while increased the number of B and helper and regulatory T cells. These combined data suggest that inhaled spectinamide 1599 combined with BPa is an effective TB regimen that avoids L-associated AEs.Tuberculosis (TB) is an airborne infectious disease that spreads via aerosols containing Mycobacterium tuberculosis (Mtb), the causative agent of TB. TB can be cured by administration of 3-4 drugs for 6-9 months but there are limited treatment options for patients infected with multidrug (MDR) and extensively resistant (XDR) strains of Mtb. BPaL is a new all-oral combination of drugs consisting of Bedaquiline (B), Pretomanid (Pa) and Linezolid (L). This regimen was able to cure ∼90% of MDR and XDR TB patients in clinical trials but many patients developed severe adverse effects (AEs) associated to the long-term administration of linezolid. We evaluated a new regimen in which Linezolid in the BPaL regimen was replaced with inhaled spectinamide 1599. In the current study, we demonstrate that 4-weeks of treatment with inhaled spectinamide 1599 in combination with Bedaquiline and Pretomanid has equivalent efficacy to the BPaL drug combination and avoids the L-associated-AEs.
DNA methylome regulates virulence and metabolism in Pseudomonas syringae
Authors: Huang Jiadai , Chen Fang , Lu Beifang , Sun Yue , Li Youyue , Hua Canfeng , Deng Xin
Published: April 2024

Bacterial pathogens employ epigenetic mechanisms, including DNA methylation, to adapt to environmental changes, and these mechanisms play important roles in various biological processes. Pseudomonas syringae is a model phytopathogenic bacterium, but its methylome is less well known than that of other species. In this study, we conducted single-molecule real-time sequencing to profile the DNA methylation landscape in three model pathovars of P. syringae. We identified one Type I restriction–modification system (HsdMSR), including the conserved sequence motif associated with N6-methyladenine (6mA). About 25–40% of the genes involved in DNA methylation were conserved in two or more of the strains, revealing the functional conservation of methylation in P. syringae. Subsequent transcriptomic analysis highlighted the involvement of HsdMSR in virulent and metabolic pathways, including the Type III secretion system, biofilm formation, and translational efficiency. The regulatory effect of HsdMSR on transcription was dependent on both strands being fully 6mA methylated. Overall, this work illustrated the methylation profile in P. syringae and the critical involvement of DNA methylation in regulating virulence and metabolism. Thus, this work contributes to a deeper understanding of epigenetic transcriptional control in P. syringae and related bacteria.
Special issue on software citation, indexing, and discoverability
Authors: Katz Daniel S. , Chue Hong Neil P.
Published: April 2024

Software plays a fundamental role in research as a tool, an output, or even as an object of study. This special issue on software citation, indexing, and discoverability brings together five papers examining different aspects of how the use of software is recorded and made available to others. It describes new work on datasets that enable large-scale analysis of the evolution of software usage and citation, that presents evidence of increased citation rates when software artifacts are released, that provides guidance for registries and repositories to support software citation and findability, and that shows there are still barriers to improving and formalising software citation and publication practice. As the use of software increases further, driven by modern research methods, addressing the barriers to software citation and discoverability will encourage greater sharing and reuse of software, in turn enabling research progress.
Otimização de rotas de transporte em estradas florestais: um estudo de caso em Paraopeba/MG
Authors: Ramos Marcos de Paulo , Gonçalves Isabella Alves , Nero Marcelo Antonio , Bortone Thiago Pena , Martini Rachel Jardim , Temba Plinio da Costa
Published: April 2024

As estradas florestais desempenham um papel crucial na ligação entre as áreas de cultivo e os locais de armazenamento e processamento. Devido à importância significativa das estradas para o setor florestal e a necessidade de reduzir os custos das operações florestais relacionadas à logística, a proposta de alternativas para otimizar as rotas dos veículos de carga ao longo de uma rede de estradas, com o objetivo de minimizar as distâncias, constitui um problema muito comum na tomada de decisões. Este trabalho tem como objetivo estudar e determinar as melhores rotas de transporte de madeira em estradas florestais utilizando ferramentas de análise e roteirização baseadas em Sistemas de Informações Geográficas (SIG). Para isso, foram empregadas ferramentas de análise espacial, preparação dos dados com o uso de técnicas de geoprocessamento, fragmentação da rede viária em "arcos-nós", visitas a campo, definição dos pontos de origem e destino e a ferramenta de análise de rede Network Analyst, uma extensão do SIG ArcGIS. As novas rotas simuladas possibilitaram o transporte de madeira até a planta de carbonização com menor distância, maior segurança e menor tempo de percurso, além de possibilitar a classificação das estradas florestais. As análises realizadas permitiram a criação de um modelo de geoprocessamento que poderá ser aplicado em outras áreas para aprimorar e/ou otimizar as rotas de transporte em estradas florestais. Portanto, o método utilizado é adequado para o planejamento e determinação das melhores rotas de transporte em estradas florestais, mostrando-se de grande importância para o desenvolvimento tecnológico e a competitividade do processo logístico, visando uma maior eficiência no transporte de qualquer tipo de carga.
Correlation of Serum Neutrophil Gelatinaseassociated Lipocalin with Clinical Severity Score in Patients with Acute Coronary Syndrome: A Cross-sectional Study
Authors: Dalai Sunanda , Devi Nirupama , Jena Jhulana Kumar , Panda Jyoti Prakash , Nanda Bijaya Lakshmi , Satpathy Saswati
Published: April 2024

Introduction: Acute Coronary Syndrome (ACS) is a term that encompasses various clinical presentations such as ST-Segment Elevation Myocardial Infarction (STEMI), Non STEMI (NSTEMI), or unstable angina. Neutrophil Gelatinase-associated Lipocalin (NGAL), also known as lipocalin-2, belongs to the lipocalin category of extracellular proteins. Recent research indicates that NGAL levels are increased in different cardiac situations, regardless of the presence of acute renal injury. Aim: To compare the levels of serum NGAL and Global Registry of Acute Coronary Events (GRACE) scores between cases with ACS and Angio-negative cases, and to study the correlation of serum NGAL with the GRACE score (clinical severity score) in ACS patients. Materials and Methods: A cross-sectional study was conducted with 128 patients at the Department of Biochemistry, MKCG Medical College and Hospital, Berhampur, Odisha, India, presenting to the Cardiac Emergency Department from November 2020 to August 2021. Coronary Angiograms (CAG) were done to confirm the presence of Coronary Artery Disease (CAD), and patients were grouped accordingly as Group-1 with ACS patients and Group-2 with angiogram-negative cases. Apart from the routine work-up, including serum urea and creatinine, serum electrolytes, fasting blood sugar, lipid profile, and management, all patients underwent determination of serum NGAL levels and GRACE score at admission. The data were analysis using student’s t-test and Pearson’s correlation test. Results: Among the 128 participants (64 cases in Group-1 and 64 cases in Group-2), Group-1 comprised 37 cases of STEMI, 26 cases of NSTEMI, and one case of unstable angina. Serum NGAL levels were significantly elevated in patients with CAGproven ACS (140.89±56.47 ng/mL) without any renal dysfunction, sepsis, or overt infection compared to patients without CAD on CAG (52.01±18.39 ng/mL) (p<0.0001). The serum NGAL level exhibited a positive correlation of 0.359 (p=0.004) with the severity of ACS, as measured by the GRACE score. Conclusion: The present study suggests that serum NGAL in patients with ACS may serve as a potential novel biomarker for risk stratification and predicting the severity of the disease.
Diagnostic Utility of Bone Marrow Aspiration, Trephine Biopsy, and Flow Cytometry in the Evaluation of Various Haematological and Non Haematological Disorders: A Cross-sectional Study from Northern India
Authors: Verma Renuka , Kalra Rajnish , Gupta Veena , Gupta Sumiti , Gupta Monika , Singh Sunita
Published: April 2024

Introduction: The spectrum of haematological and non haematological disorders is vast in various age groups. Complete blood counts and other routine laboratory tests are not always sufficient to diagnose these diseases. Bone marrow examination plays an important role in diagnosing their underlying causes. Aim: To analyse the spectrum of various haematological and non haematological disorders reported in Bone Marrow Aspiration (BMA) and compare them with Bone Marrow Trephine Biopsy (BMB) and Flow Cytometry (FCM) findings where applicable. Materials and Methods: A one-year cross-sectional study was conducted in the Department of Clinical Pathology, PGIMS, Rohtak, Haryana, India from April 2022 to March 2023. A total of 518 consecutive BMA samples were morphologically analysed. Comparative evaluations were performed among BMA, BMB, and FCM where applicable. Diagnostic accuracy was calculated, and the findings of discordant cases were tabulated. Definitive diagnosis of lymphoma/leukaemia and Paroxysmal Nocturnal Haemoglobinuria (PNH) cases were made using FCM. Results: The patients’ ages ranged from three months to 86 years, with a mean age of 38.4 years. The male to female ratio was 1.3:1, with a slight male predominance. The highest number of cases were of anaemia {183 (35.3%) and 164 (31.7%), respectively} and leukaemia {128 (24.7%) and 134 (25.9%), respectively}, followed by normal marrow studies {39 (7.5%) and 32 (6.2%), respectively} and megakaryocytic thrombocytopenia {24 (4.6% in each} in both BMA and biopsy. Among anaemia cases {183 and 164 cases in BMA and BMB}, the majority were of the megaloblastic type {62 (33.8%) and 54 (32.9%), respectively}, followed by hypoplastic/aplastic type {40 (21.8%) and 50 (30.5%), respectively}. In cases of leukaemia (128 and 134 cases in BMA and BMB), acute leukaemia cases (76 (59.4%) and 82 (61.2%), respectively} outnumbered chronic leukaemia cases {52 (40.6%) and 52 (38.8%), respectively} in both BMA and BMB. The concordance and discordance rate between BMA and BMB were 87.6% (419 cases) and 12.4% (59 cases), respectively. Diagnosis was exclusively made by BMB in cases of myelofibrosis, granulomatous disease, and Hodgkin’s lymphoma. Conclusion: BMA cytology is a relatively safe and mildly invasive technique for evaluating various haematological and non haematological disorders with better preservation of cellular morphology. However, in cases with dry/blood taps and focal marrow involvement, BMB should be performed, as it shows well-preserved marrow architecture with all its cellular and stromal components. FCM is a definitive diagnostic modality for further categorisation of acute leukaemia and Chronic Lymphoproliferative Disorders (CLPD).
Procalcitonin Levels for Prognosis of Scrub Typhus Patients: A Retrospective Observational Analysis from a Tertiary Care Centre in Northern India
Authors: Jamwal Ashima , Varghese Gerlin , Sarawat Deepika , Sahu Chinmoy , Patel Sangram Singh , Khan Mohd Rashid , Tiwari Ankita
Published: April 2024

Introduction: Scrub typhus is a major cause of acute febrile illness in India. It presents with various clinical features that vary from fever to multiorgan dysfunction. Similar symptoms and presentations cause difficulty in diagnosis. Therefore, it is important to have early and prompt diagnosis with better prognostic markers to decrease morbidity and mortality. Aim: To determine the prognosis of scrub typhus patients based on the Procalcitonin (PCT) levels. Materials and Methods: This retrospective observational study was conducted in the Microbiology Department of Sanjay Gandhi Postgraduate Institute of Medical Sciences, Uttar Pradesh, India, from January 2022 to January 2023. A total of 120 patients admitted to the hospital, who tested positive for Scrub typhus IgM by ELISA during this period and had a negative blood culture, were included in this study. Data analysis was conducted from February 2023 to April 2023. PCT levels of all these patients at the time of admission were recorded. The demographic information, laboratory parameters, and treatment regimen of these patients were also compiled. Statistical analysis was performed, and p-value was used to determine statistical significance. Results: The majority of the patients belonged to the age group of 21-40 years. Among these, elevated PCT values (ranging from 0.05-89.4 ng/mL) were observed in 112 (93.33%) patients. Twelve (10%) patients died during the study period, and all of them had elevated PCT levels. Among these, six developed septic shock with Multiple Organ Dysfunction Syndrome (MODS). Increased leukocyte values, elevated liver enzymes such as Aspartate Aminotransferase (SGOT/AST) and Alanine Transferase (SGPT/ALT), abnormal coagulation profile, and abnormal renal profile with elevated urea and uric acid levels were found to be significantly associated with scrub typhus patients with elevated PCT values. Conclusion: There is a need to address the role of prognostic markers in the management of scrub typhus patients. This may lead to breakthroughs in the field of diagnostic research and help improve the prognosis of these patients.
Sigma Metrics in Thyroid Testing: Striving for Perfection- An Observational, Cross-sectional Study
Authors: Rajib Sekh , Mukherjee Kasturi , Ghosh Bithika , Bhattacharyya Raghunath , Mukhopadhyay Mousumi
Published: April 2024

Introduction: Six Sigma is a potent tool for evaluating the quality of the analytical phase by combining bias, imprecision, and Total Allowable Error (TEa). Considering the variation in TEa values from different sources, analysis on the sigma scale needs to be carefully monitored. Aim: To assess the performance of Thyroid Stimulating Hormone (TSH) and free Thyroxine (fT4) on the Sigma scale. Materials and Methods: The present observational, cross- sectional study Immunoassay laboratory at the Department of Biochemistry, IPGMER and SSKM Hospital, Kolkata, India, from February 2021 to January 2022. The study involves 12 months of tri-level (L1, L2, L3) Internal Quality (IQ) control data and External Quality Assessment (EQAS) data. The bias percentage was obtained from EQAS, and the Coefficient of Variation (CV%) was obtained from IQ Control (IQC) data run on Advia Centaur CP (CLIA) each month. Sigma (σ) was calculated applying TEa from the desirable biological variation database. Sigma values of L1, L2, L3 of TSH and fT4 have been calculated using Microsoft spreadsheet software version 2010, applying the formula σ= (TEa-bias)/CV. Results: The CV% and bias% were found to be within an acceptable range, always less than the cut-off percentage of imprecision (I%) and inaccuracy (B%) for TSH and fT4 in the desirable specifications for imprecision and inaccuracy (updated 2014). However, sigma levels are near the satisfactory mark, found to be <5σ over 17 months for TSH and 23 months for fT4, considering all sigma values of L1, L2, and L3 IQ levels. Better sigma values (>5σ) in tri-level IQ for TSH with a higher numeric TEa% value (23.7%) were obtained in more months, whereas for fT4 with a lower TEa% value (8%), better sigma values (>5σ) were obtained in a lesser number of months. Conclusion: The present study establishes that Sigma values are affected by the numeric values of TEa% of a particular parameter taken from the source. Sigma values showed average performance despite satisfactory CV% and bias% for fT4 and TSH, creating chaos in the laboratory’s operational routine. The Sigma matrix is a good indicator, but it is difficult to maintain a good sigma value for parameters that have low TEa%. It becomes crucial to choose appropriate TEa to plan a quality control strategy for thyroid hormones.