bluuebunny/crossref_metadata_2025_split huggingface dataset:
Differential Impact of the FMR-1 Full Mutation on Memory and Attention Functioning: A Neuropsychological Perspective
Authors: Cornish Kim M. , Munir Fehmidah , Cross Gareth 
Published: July 2002

AbstractMemory and attention processing were examined in a group of 15 adult Fragile-X syndrome (FXS) males with Fragile-X mental retardation 1 (FMR-1) full mutation and compared to two control groups: a learning disabled (LD) control and a normal functioning control. Performance was assessed across a wide range of tasks including working memory, recognition memory, selective attention, sustained attention, and attentional switching. All three groups performed at a comparable level on recognition memory tasks, and the Fragile-X males and LD control group performed worse than the control group on tasks of working memory and sustained attention. On a task of executive function, the Fragile-X males demonstrated a significant deficit in comparison to the LD control group and the normal control group, but performed better than the LD control group and at a comparable level to the control group on tasks of selective attention. Molecular analyses of the lymphocyte DNA provided little evidence for a correlation between expansion size and performance on tasks of memory and attention. The findings from the present study are discussed in the context of functional neuroimaging and brain-behavior-molecular correlates.
Magmatic and metasomatic processes during formation of the Nb-Zr-REE deposits Khaldzan Buregte and Tsakhir (Mongolian Altai): Indications from a combined CL-SEM Study
Authors: Kempe U. , Götze J. , Dandar S. , Habermann D. 
Published: July 2002

AbstractCathodoluminescence (CL) imaging and spectroscopy, as well as backscattered electron imaging, were used to assign the occurrence of several mineral phases and rock structures in altered nordmarkites and calcite-bearing granites from the Nb-Zr-REE deposits from Khaldzan Buregte and Tsakhir (Mongolian Altai) to three events: (1) intrusion of barren nordmarkites; (2) intrusion of small bodies of calcite-bearing granites with metasomatic alteration of the wall-rocks; and (3) alteration by F-rich fluids.Unusual red and yellow CL caused by Fe3+ and Mn2+ emission centres were detected in microcline and albite. Fe3+ centres were also established (along with others) in quartz, zircon, and possibly in fluorite.Magmatic and metasomatic rock structures and internal structures of the minerals coexist in the samples. The primary magmatic features were in part preserved during alteration. In contrast, the internal and the centre structures may be changed during alteration even in non-replaced mineral phases. Euhedral minerals may be formed by secondary processes as shown for lath-shaped albite. The occurrence of pseudomorphs, the inheritance of elements during replacement, and the mechanical effects of secondary minerals on earlier mineral phases during metasomatic growth are proposed as criteria for the reconstruction of the mineral succession in altered rocks. Snowball structures may be formed as a result of metasomatic alteration rather than as a magmatic intergrowth.
Increases in circulating and lymphoid tissue interleukin-10 in autoimmune lymphoproliferative syndrome are associated with disease expression
Authors: Lopatin Uri , Yao Xu , Williams Richard K. , Bleesing Jack J. H. , Dale Janet K. , Wong David , Teruya-Feldstein Julie , Fritz Scott , Morrow Matthew R. , Fuss Ivan , Sneller Michael C. , Raffeld Mark , Fleisher Thomas A. , Puck Jennifer M. , Strober Warren , Jaffe Elaine S. , Straus Stephen E. 
Published: July 2002

AbstractAutoimmune lymphoproliferative syndrome (ALPS) is an inherited disorder in which genetic defects in proteins that mediate lymphocyte apoptosis, most often Fas, are associated with enlargement of lymph nodes and the spleen and a variety of autoimmune manifestations. Some patients with ALPS have relatives with these same apoptotic defects, however, who are clinically well. This study showed that the circulating levels of interleukin 10 (IL-10) were significantly higher (P &lt; .001) in 21 patients with ALPS than in healthy controls. Moreover, the peripheral blood mononuclear cells (PBMCs) and lymphoid tissues of these patients with ALPS contained significantly higher levels of IL-10 messenger RNA (mRNA;P &lt; .001 and P &lt; .01, respectively). By fractionating PBMC populations, disproportionately high concentrations of IL-10 mRNA were found in the CD4−CD8−T-cell population, expansion of which is virtually pathognomonic for ALPS. Immunohistochemical staining showed intense IL-10 protein signals in lymph node regions known to contain CD4−CD8− T cells. Nonetheless, in vitro studies showed no influence of IL-10 on the survival of CD4−CD8− T cells. Overexpression of IL-10 in patients with inherited apoptotic defects is strongly associated with the overt manifestations of ALPS.
Altered T-cell receptor + CD28-mediated signaling and blocked cell cycle progression in interleukin 10 and transforming growth factor-β–treated alloreactive T cells that do not induce graft-versus-host disease
Authors: Boussiotis Vassiliki A. , Chen Zong-Ming , Zeller Jay C. , Murphy William J. , Berezovskaya Alla , Narula Satwant , Roncarolo Maria G. , Blazar Bruce R. 
Published: July 2002

AbstractThe induction of anergy in T cells, although widely accepted as critical for the maintenance of tolerance, is still poorly understood at the molecular level. Recent evidence demonstrates that in addition to blockade of costimulation using monoclonal antibodies (mAbs) directed against cell surface determinants, treatment of mixed lymphocyte reaction (MLR) cultures with interleukin 10 (IL-10) and transforming growth factor-β (TGF-β) results in induction of tolerance, rendering alloreactive murine CD4+ T cells incapable of inducing graft-versus-host disease (GVHD) after in vivo transfer to histoincompatible recipients. The present study, using these cells prior to adoptive transfer, determined that IL-10 + TGF-β–tolerant CD4+ T cells exhibit an altered pattern of T-cell receptor (TCR) + CD28-mediated signaling and are incapable of progressing out of the G1 phase of the cell cycle during stimulation with HLA class II disparate antigen-presenting cells. TGFβ + IL-10–tolerant cells were incapable of phosphorylating TCR-ζ, or activating ZAP-70, Ras, and MAPK, similarly to T-cell tolerized by blockade of B7/CD28 and CD40/CD40L pathways. Moreover, these cells were incapable of clonal expansion due to defective synthesis of cyclin D3 and cyclin A, and defective activation of cyclin-dependent kinase (cdk)4, cdk6, and cdk2. These cells also exhibited defective down-regulation of p27kip1 cdk inhibitor and lack of cyclin D2-cdk4 activation, Rb hyperphosphorylation, and progression to the S phase of the cell cycle. These data link anergy-specific proximal biochemical alterations and the downstream nuclear pathways that control T-cell expansion and provide a biochemical profile of IL-10 + TGF-β–tolerant alloreactive T cells that do not induce GVHD when transferred into MHC class II disparate recipients in vivo.
Caspase 8 activation independent of Fas (CD95/APO-1) signaling may mediate killing of B-chronic lymphocytic leukemia cells by cytotoxic drugs or γ radiation
Authors: Jones Dylan T. , Ganeshaguru Kanagasabai , Virchis Andres E. , Folarin Najeem I. , Lowdell Mark W. , Mehta Atul B. , Prentice H. Grant , Hoffbrand A. Victor , Wickremasinghe R. Gitendra 
Published: July 2002

Abstract
Ligation of the cell-surface Fas molecule by its ligand (Fas-L) or agonistic anti-Fas monoclonal antibodies results in the cleavage and activation of the cysteine protease procaspase 8 followed by the activation of procaspase 3 and by apoptosis. In some leukemia cell lines, cytotoxic drugs induce expression of Fas-L, which may contribute to cell killing through the ligation of Fas. The involvement of Fas, Fas-L, and caspase 8 was studied in the killing of B-cell chronic lymphocytic leukemia (B-CLL) cells by chlorambucil, fludarabine, or γ radiation. Spontaneous apoptosis was observed at 24-hour incubation, with additional apoptosis induced by each of the cytotoxic treatments. Although Fas mRNA expression was elevated after exposure to chlorambucil, fludarabine, or γ radiation, Fas protein levels only increased after irradiation. Therefore, Fas expression may be regulated by multiple mechanisms that allow the translation of Fas mRNA only in response to restricted cytotoxic stimuli. None of the cytotoxic stimuli studied here induced Fas-L expression. An agonistic anti-Fas monoclonal antibody (CH-11) did not significantly augment apoptosis induction by any of the death stimuli. A Fas-blocking antibody (ZB4) did not inhibit spontaneous, chlorambucil-, fludarabine-, or radiation-induced apoptosis. However, procaspase 8 processing was induced by all cytotoxic stimuli. These data suggest that the Fas/Fas-L signaling system does not play a major role in the induction of apoptosis in B-CLL cells treated with cytotoxic drugs or radiation. However, Fas-independent activation of caspase 8 may play a crucial role in the regulation of apoptosis in these cells.
Experience of Older Adults and Their Family Members in the Kidney Transplant Evaluation
Authors: Butler Catherine R. , Gaughran Olivia A. , Taylor Janelle S. , Gee Patrick O. , O’Hare Ann M. 
Published: December 2024

ImportanceTransplant can be a valuable treatment option for older adults with kidney failure, and recent initiatives encourage more frequent referral to transplant centers. However, the evaluation process can be challenging, and most older adults do not ultimately receive a kidney.ObjectiveTo elucidate the perspectives and experiences of older adults with advanced kidney disease and their family members regarding the kidney transplant evaluation process.Design, Setting, and ParticipantsThis qualitative study, conducted between December 19, 2022, and February 5, 2024, included adults aged 65 years or older with advanced kidney disease (estimated glomerular filtration rate ≤20 mL/min/1.73 m2, receiving dialysis, or with a functioning kidney transplant) and their family members in Seattle, Washington.Main Outcomes and MeasuresPerspectives and experiences of patients and family members, identified through inductive thematic analysis of semi-structured interviews.ResultsA total of 26 older adults (16 [61.5%] men; median age, 68 years [range, 65-74 years]) with advanced kidney disease and 7 of their family members (4 [57.1%] women; median age, 65 years [range, 36-75 years]) were interviewed. Three dominant themes pertaining to the kidney transplant evaluation process were identified: (1) committed to transplant, (2) a complex and protracted process, and (3) responsibility without power. Because receiving a kidney was such an important priority, most participants were willing to engage in what could be a demanding process of testing and treatment narrowly focused on this future goal. However, the transplant evaluation could be lengthy, demanding, opaque, and fragmented, and patients often put other aspects of their lives on hold while awaiting an uncertain result. Patients and families often felt personally responsible for navigating and completing the transplant evaluation despite having little power to shape this process. Feeling responsible for the continued progress of a high-stakes evaluation process while remaining dependent on clinical teams and family members for support could strain relationships.Conclusions and RelevanceThis qualitative study found that older adults with advanced kidney disease and their family members were highly motivated to receive a kidney transplant but engagement in an evaluation process, over which they had little control, could have far-reaching implications for patients and families. These findings underline the importance of making the transplant evaluation process more transparent and person centered and of helping patients and families who are contemplating or engaged in the process to understand what to expect.
Adaptive Antenna Arrays
Authors: Sun Chen , Karmakar Nemai C. , Zomorodi Mohammad , Nguyen Dong H. 
Published: December 2024

Abstract
Adaptive array antennas play an important role in wireless communications systems. The article begins with a brief introduction to the evolution of wireless communications systems and demands for adaptive array antennas. After that, the current and future applications of adaptive array antennas in wireless communications systems are described. Next, the structures and implementations of the adaptive array antenna systems, including switched‐beam antennas, phased‐array antennas, digital beamforming (DBF) array antennas, parasitic array antennas, diversity antennas, and multiple input multiple output (MIMO), are discussed. The article concludes with a comparison of different adaptive array antenna architectures.
Radiation Patterns
Authors: Chryssomallis Michael , Christodoulou Christos 
Published: December 2024

Abstract

The radiation pattern of an antenna is one of its basic properties since it shows the way the antenna distributes its energy in space. It generally consists of a number of lobes, and if it is measured far away from the antenna, it is independent of distance. It is a function of angles and can be expressed as field or power pattern. It usually can be completely specified from the patterns in two planes, perpendicular to each other, the
E
‐ and
H
‐plane, respectively. Related to the radiation pattern of an antenna, a number of important parameters exist, such as radiation power density, beamwidth, radiation and beam efficiency, directivity, gain, and antenna polarization.

The subject of this article is to provide an introduction to radiation patterns and all the related important parameters. The content is organized in four sections. The first section introduces several antenna patterns, giving the necessary definitions and presenting the common types. The field regions of an antenna are also pointed out. In the second section, after the introduction of Poynting vector and radiation power density, radiation performance measures such as the beam solid angle, directivity, and gain of an antenna are defined. In the third section, the concepts of wave and antenna polarization are discussed. Finally, in the fourth section, a general case of antenna pattern calculation is considered, and numerical solutions are suggested for radiation patterns that are not available in simple closed‐form expressions.
Chirality
Authors: Lakhtakia Akhlesh 
Published: December 2024

Abstract
Chiral media have the ability to discriminate between left‐ and right‐handed electromagnetic fields. These media can be classified into two types: (1) isotropic chiral media and (2) structurally chiral media. The molecules of a naturally occurring isotropic chiral medium are handed, while an artificial chiral medium can be made by randomly dispersing electrically small, handed inclusions (such as springs) in an isotropic achiral host medium. The molecules or inclusions in a structurally chiral medium, such as a chiral nematic liquid crystal, are randomly positioned but have helicoidal orientational order. Structurally chiral media can also be artificially fabricated either as stacks of uniaxial laminae or using thin‐film technology. Formulations for electromagnetic fields in both classes of chiral media are succinctly presented here.
Frequency Independent Antennas
Authors: Cencich Thomas P. , Samson Timothy 
Published: December 2024

Abstract
Frequency‐independent (FI) antennas are radiating structures capable of maintaining consistent impedance and pattern characteristics over multiple‐decade bandwidths. Their finite size limits the lowest frequency of operation, and the finite precision of the center region bounds the highest frequency of operation. The geometry of an FI antenna must be specified by angles alone, and principles such as truncation and self‐complementarity are necessary and desired, respectively. In this chapter, Rumsey's theory of FI antennas, developed in the mid‐1950s, is thoroughly discussed, and historical highlights listing the most important contributions in this area are given. A mathematical derivation for a general FI structure is provided, and some special cases are considered both theoretically and practically. A description and an explanation of the underlying theory of operation for several FI antenna types, including equiangular spirals, conventional and unconventional sinuous antennas, and log‐periodic folded slot arrays, are also provided. A view of frequency independence through the modal content and contamination of the radiated far field is emphasized. Considerations for flush/conformal mounting are briefly discussed, including the use of log‐periodic lossless cavities and broadband conical cavities. Several examples of FI antenna hardware are shown.
Lens Antennas
Authors: Malherbe Johannes A. G. 
Published: December 2024

Abstract

Lenses can be employed to act as high‐gain scannable antennas. The optical principles that apply to lens antennas are discussed, as well as the materials used in the construction of lenses. The basic lens function is discussed, and examples given of simple planoconvex and planoconcave lenses, together with the equations that describe the lens surfaces. In order to reduce the lens size, lenses are zoned, and equations for lens zoning are given. Other lens parameters such as gain, sidelobe level, reflections, loss, and bandwidth are treated. Lens systems for scannable or multibeam antennas are described, and design and analysis procedures for Rotman lenses given. Other lenses discussed include Luneburg,
R
‐2
R
, integrated dielectric, and Fresnel zone lenses. Physical construction methods for Rotman, Luneburg, and Fresnel zone plate lenses are discussed. This includes three‐dimensional (3D) printing and use of metamaterials.
Yagi–Uda Antenna
Authors: Kaneda Noriaki , Deal William R. 
Published: December 2024

Abstract
The Yagi–Uda antenna is one of the most practical and commonly used antennas. It features high gain, low weight and profile, and is inexpensive to manufacture. In this article, the fundamental operation of the Yagi–Uda, as well as a classic graphical technique for obtaining a fixed gain design, is discussed. Several modern versions of the Yagi–Uda antenna are also described, which permit the antenna to be operated at microwave frequencies and allow for simple integration into planar arrays in various applications including modern wireless communications.
Finite‐Difference Time‐Domain Analysis Advances
Authors: Yu Wenhua , Zhang Xin 
Published: December 2024

Abstract
The finite‐difference time‐domain (FDTD) method is one of key numerical techniques to solve Maxwell's equations, which has the broad applications for a variety of electromagnetic problems such as electromagnetic propagation, electromagnetic compatibility (EMC), and electromagnetic interference (EMI). This article first reviews the basic FDTD techniques such as update equations, numerical dispersion, stability properties, boundary conditions and conformal techniques, and then focuses on some enhanced FDTD techniques such as parallelization techniques and hardware acceleration techniques that can be greatly used to extend applications of the regular FDTD methods.
RF MOSFETs
Authors: Kumari Vandana , Gupta Mridula , Saxena Manoj 
Published: December 2024

Abstract
In this article, the RF performance of different MOSFET architectures such as Silicon‐On‐Insulator (SOI), Lightly Doped Drain (LDD) MOSFET, Graphene FET, and Negative Capacitance (NC) FET have been reported based on the previously reported work in the form of equivalent circuits. Using the data reported in the literature, the cutoff frequency and maximum frequency of oscillation have been summarized with varying channel lengths. Compared results show that multigate architecture results in higher cutoff frequency and a maximum frequency of oscillation, which can be further increased by decreasing the channel length of the MOSFET architecture. However, the deterioration in the resulting device gain at lower channel length has also been reported. Furthermore, the performance of SOI, Silicon‐on‐Nothing (SON), Double Gate (DG), Double‐Gate Silicon‐On‐Insulator (DGSOI), and Empty Space in Double‐Gate (ESDG) architectures have been explored using ATLAS TCAD software tool for RF and digital parameters investigation. The various parameters explored in this article are current density, electric field, breakdown voltage, impact ionization rate, scattering parameters, noise conductance, minimum noise figure, and cross‐correlation factor. The presented results show that, for the same drain current value, ESDG architecture has higher device gain compared to other devices used for comparison along with higher cutoff frequency. However, this higher device gain comes at the cost of a slightly higher minimum noise figure but with improved noise conductance and cross‐correlation factor (slightly higher than DG). Thus, ESDG is a reliable candidate for LNA design compared to other devices.
Stability of Nonlinear Systems
Authors: Chen Guanrong 
Published: December 2024

Abstract
This chapter briefly presents the notion of stability of nonlinear systems in both continuous‐time and discrete‐time settings. Basic concepts and fundamental theorems of various system stabilities are introduced. These mainly include the important Lyapunov stability theory, along with some others particularly the orbital stability and the structural stability. The bounded‐input bounded‐output stability of maps is also discussed.
Antenna Testing and Measurements
Authors: Kefauver W. Neill , Samson Timothy 
Published: December 2024

Abstract
Antenna measurements have a wide range of end uses; in many cases, the need is to verify as‐built performance against the evermore sophisticated design tools. These electromagnetic design tools now include details on surface roughness and dielectric loading with computational speeds that make these problem easily completed on engineering workstation that would have required supercomputers a decade ago. In addition, the resulting simulations can be tied from RF (radio frequency) fields into detailed physics associated with power handling due to heat, corona breakdown, saturation, and multipaction. Properly verifying the performance has hence become more complex as the margins continue to be reduced on as‐built designs, and the antennas have more embedded electronics.
Antenna measurements have thus become more detailed with the increasing complexity of antennas. In the 1950s, the phase or quadrature response of the antenna was not required for many systems, only power detection was necessary. As the systems started to use techniques of phase and frequency modulation, the measurement of phase became more essential to characterizing system performance and improving polarization data also. Next, the need for knowledge extended to frequency and eventually time domain as increasingly the antenna became another electronic component in the microwave designers' tool kit. In the 2000s, the antenna has evolved into a shaped multibeam, polarization, and frequency agile device, not just for the military but for communications systems as well. In application, the next generation, from the 2020s onward, will see the concept of an antenna become blurred as the digital realm begins to reach down into the final layers of RF devices to the antenna itself.
Not all antenna testing is providing measurements of fields, but for this article, the author will not investigate testing that is not unique to antennas, such as temperature, vibration, shock, humidity, stress, wind, and other possibilities. Unless the RF properties are part of the performance evaluated during these other types of tests, the testing methods would be the same as for any black box taken to an environmental test facility.