bluuebunny/crossref_metadata_2025 huggingface dataset:
Asymmetric memory hierarchies
Authors: Williams John G.
Published: July 2002

A study is presented of some of the system implications of memory hierarchies in which the backing or secondary store has a very small read time, relative to both the time required for writing and to the read time of conventional backing storage devices. Several analytic models are introduced, and it is shown that such hierarchies may operate in ways which differ from those of more conventional hierarchies. In particular, it is shown that it may not be necessary to multiprogram in such a situation.

In the past, backing storage devices have been roughly symmetric with respect to their read and write times. This situation may not continue, as several devices are currently under development which may have a very small read-time/write-time ratio. This study places particular emphasis on one such system—the RCA read/write holographic optical memory.
A number system for the permutations
Authors: Pager David
Published: July 2002

A number system described here is particularly suitable for numbering the permutations. An algorithm is then presented by which the permutation associated with a number of this kind may be obtained. Since arithmetical operations, such as the addition of 1, are easily performed in the number system, one may make use of the algorithm to generate the permutations one at a time, using a minimal amount of work space. Employed for this purpose, it provides an alternative to the method given in [1].
Algorithm 449: solution of linear programming problems in 0-1 variables
Authors: Fiala František
Published: July 2002

This subroutine solves the linear zero-one programming problem of the following form.
Directed random generation of sentences
Authors: Friedman Joyce
Published: July 2002

The problem of producing sentences of a transformational grammar by using a random generator to create phrase structure trees for input to the lexical insertion and transformational phases is discussed. A purely random generator will produce base trees which will be blocked by the transformations, and which are frequently too long to be of practical interest. A solution is offered in the form of a computer program which allows the user to constrain and direct the generation by the simple but powerful device of restricted subtrees. The program is a directed random generator which accepts as input a subtree with restrictions and produces around it a tree which satisfies the restrictions and is ready for the next phase of the grammar. The underlying linguistic model is that of Noam Chomsky, as presented in
Aspects of the Theory of Syntax
. The program is written in FORTRAN IV for the IBM 360/67 and is part of a unified computer system for transformational grammar. It is currently being used with several partial grammars of English.
Variable length tree structures having minimum average search time
Authors: Patt Yale N.
Published: July 2002

Sussenguth suggests in a paper (1963) that a file should be organized as a doubly-chained tree structure if it is necessary both to search and to update frequently. Such a structure provides a compromise between the fast search/slow update characteristics of binary searching and the slow search/fast update characteristics of serial searching. His method, however, contains the limiting restriction that all terminal nodes lie on the same level of the tree. This paper considers the effect of relaxing this restriction.

First, trees which have the property that a priori the filial set of each node is well defined are studied. It is proved that coding the nodes within each filial set with respect to the number of terminal nodes reachable from each is necessary and sufficient to guarantee minimum average search time.

Then the more general case (that is, where the entire structure of the tree is changeable) is treated. A procedure is developed for constructing a tree with a minimum average search time. A simple closed expression for this minimum average search time is obtained as a function of the number of terminal nodes. The storage capacity required to implement the doubly-chained tree structure on a digital computer is also determined. Finally, the total cost of the structure, using Sussenguth's cost criterion, is computed. It is shown that significant improvements in both the average search time and the total cost can be obtained by relaxing Sussenguth's restriction that all terminal nodes lie on the same level of the tree.
Randomized binary search technique
Authors: Arora S. R. , Dent W. T.
Published: July 2002

A mathematical model is developed for the mean and variance of the number of trials to recover a given document in a randomly received list of files. The search method described is binary in nature and offers new potential for information retrieval systems.
Loader standardization for overlay programs
Authors: Lanzano Bernadine C.
Published: July 2002

The overlay capability is described for four of the third generation computer systems: CDC-6000, GE-635, IBM-360, and UNIVAC-1108. A critique of the first three sytems is based on actual experience with a large overlaid trajectory simulation program; a short history and description of this program is presented. A standardization of minimum capabilities for loaders is recommended so that programs which must operate under more than one computer system may be easily converted and maintained. A proposal that overlay software incorporates a memory occupation specification concept instead of the conventional tree structure is delineated. This concept provides more efficient and cost-effective utilization of the memory as well as increasd flexibility in program structure.
Constraint-type statements in programming languages
Authors: Wilkes M. V.
Published: July 2002

A proposal is made for including in a programming language statements which imply relations between variables but which are not explicit assignment statements. The compiler sets up a Newtonian iteration making use for the purpose of a routine for formal differentiation.
Algorithm 279: Chebyshev quadrature
Authors: Hopgood F. R. A. , Litherland C.
Published: July 2002

It has always been obvious that the aid to calculation offered by the computer forces a change in the curricula of mathematics, statistics, physics, engineering and other courses. Not so obvious are the many pedagogic aids the computer can offer in teaching the subject matter. The possibilities of giving the student a better technical as well as conceptual understanding of statistics were explored for a number of years at the College of Medicine of the University of Cincinnati and are reported here.
Language features for flexible handling of exceptions in information systems
Authors: Borgida Alexander
Published: July 2002

An exception-handling facility suitable for languages used to implement database-intensive information systems is presented. Such a mechanism facilitates the development and maintenance of more flexible software systems by supporting the abstraction of details concerning special or abnormal occurrences. The type constraints imposed by the schema as well as various semantic integrity assertions are considered to be normalcy conditions, and the key contribution of this work is to allow exceptions to these constraints to persist. To achieve this, solutions are proposed to a range of problems, including sharing and computing with exceptional information, exception handling by users, the logic of constraints with exceptions, and implementation issues. The use of exception handling in dealing with null values, estimates, and measurement is also illustrated.
When experts agree
Authors: Bharat Krishna , Mihaila George A.
Published: July 2002

In response to a query, a search engine returns a ranked list of documents. If the query is about a popular topic (i.e., it matches many documents), then the returned list is usually too long to view fully. Studies show that users usually look at only the top 10 to 20 results. However, we can exploit the fact that the best targets for popular topics are usually linked to by enthusiasts in the same domain. In this paper, we propose a novel ranking scheme for popular topics that places the most
authoritative
pages on the query topic at the top of the ranking. Our algorithm operates on a special index of "expert documents." These are a subset of the pages on the WWW identified as directories of links to non-affiliated sources on specific topics. Results are ranked based on the match between the query and relevant descriptive text for hyperlinks on expert pages pointing to a given result page. We present a prototype search engine that implements our ranking scheme and discuss its performance. With a relatively small (2.5 million page) expert index, our algorithm was able to perform comparably on popular queries with the best of the mainstream search engines.
The design and building of Enchère, a distributed electronic marketing system
Authors: Banâtre Jean-Pierre , Banâtre Michel , Lapalme Guy , Ployette Florimond
Published: July 2002

Building and prototyping an agricultural electronic marketing system involved experimenting with distributed synchronization, atomic activity, and commit protocols and recovery algorithms.
Biomedical Ethics and the Withdrawal of Advanced Life Support
Authors: Henig Noreen R. , Faul John L. , Raffin Thomas A.
Published: July 2002

▪ Abstract  It is common for health care providers to deal with the complex and difficult issue of withdrawing advanced life support. The patient is always the key source of authority in these decisions. The most important ingredient in end-of-life decision making is effective communication. It is important to try to ascertain what the patient thought about quality-of-life values before surrogate decisions can be made on the patient's behalf. The concepts of beneficence, nonmaleficence, autonomy, and justice are the foundation of ethical decision making. Numerous legal precedents have laid the groundwork for end-of-life decision making. Most state courts have supported withholding and withdrawing life support from patients who will not regain a reasonable quality of life. The recent Patient Self-Determination Act encourages patients to fill out advance directives that state their desires. When continued intensive care is futile, advanced life support should be withdrawn. However, a narrow definition of futility in this situation is the key, since the concept of futility could lead to inappropriate decisions. It is best to consider a situation futile when the patient is terminally ill, the condition is irreversible, and death is imminent. During the withdrawal of advanced life support, terminal or rapid weaning is preferable to extubation. Combinations of opiates, benzodiazepines, and other agents help provide comfort to patients who are suffering.
From Chick Nutrition to Nutrition Policy
Authors: Hegsted D. M.
Published: July 2002

It is difficult to abstract a summary of a lifetime of work. I have chosen to discuss research on protein, calcium, and the effects of dietary fat and cholesterol on serum cholesterol and on my activities that led to the publication of the Dietary Guidelines for Americans. Among the conclusions from studies on protein and calcium is that reasonably healthy people are adapted to their current diets. People all over the world, for example, are raised on relatively low calcium intakes yet have less osteoporosis than those who consume western-style diets. They also appear to do reasonably well on low-lysine intakes. Attempts to define requirements need to allow for adaptation, and we need to determine whether such adaptations are beneficial or detrimental to health. The studies on serum cholesterol defined the role of the various classes of fatty acids. The publication of the Dietary Guidelines for Americans introduced a new era of nutrition and has radically altered nutrition policy, nutrition standards, and education.
Cerebral Specialization for Speech and Non-Speech Stimuli in Infants
Authors: Dehaene-Lambertz G.
Published: July 2002

Early cerebral specialization and lateralization for auditory processing in 4-month-old infants was studied by recording high-density evoked potentials to acoustical and phonetic changes in a series of repeated stimuli (either tones or syllables). Mismatch responses to these stimuli exhibit a distinct topography suggesting that different neural networks within the temporal lobe are involved in the perception and representation of the different features of an auditory stimulus. These data confirm that specialized modules are present within the auditory cortex very early in development. However, both for syllables and continuous tones, higher voltages were recorded over the left hemisphere than over the right with no significant interaction of hemisphere by type of stimuli. This suggests that there is no greater left hemisphere involvement in phonetic processing than in acoustic processing during the first months of life.
Perceptual and Semantic Components of Memory for Objects and Faces: A PET Study
Authors: Simons Jon S. , Graham Kim S. , Owen Adrian M. , Patterson Karalyn , Hodges John R.
Published: July 2002

Previous studies have suggested differences in the neural substrates of recognition memory when the contributions of perceptual and semantic information are manipulated. In a within-subjects design PET study, we investigated the neural correlates of the following factors: material type (objects or faces), semantic knowledge (familiar or unfamiliar items), and perceptual similarity at study and test (identical or different pictures). There was consistent material-specific lateralization in frontal and temporal lobe regions when the retrieval of different types of nonverbal stimuli was compared, with objects activating bilateral areas and faces preferentially activating the right hemisphere. Retrieval of memories for nameable, familiar items was associated with increased activation in the left ventrolateral prefrontal cortex, while memory for unfamiliar items involved occipital regions. Recognition memory for different pictures of the same item at study and test produced blood flow increase in left inferior temporal cortex. These results have implications for our understanding of the neural correlates of perceptual and semantic contributions to recognition memory.
Relation Between Retinotopical and Orientation Maps in Visual Cortex
Authors: Ernst Udo , Pawelzik Klaus , Tsodyks Misha , Sejnowski Terrence J.
Published: July 2002

A recent study of cat visual cortex reported abrupt changes in the positions of the receptive fields of adjacent neurons whose preferred orientations strongly differed (Das & Gilbert, 1997). Using a simple cortical model, we show that this covariation of discontinuities in maps of orientation preference and local distortions in maps of visual space reflects collective effects of the lateral cortical feedback.
Embodiment of Evolutionary Computation in General Agents
Authors: Smith Robert E. , Bonacina Claudio , Kearney Paul , Merlat Walter
Published: July 2002

Holland's Adaptation in Natural and Artificial Systems largely dealt with how systems, comprised of many self-interested entities, can and should adapt as a whole. This seminal book led to the last 25 years of work in geneticalgorithms (GAs) and related forms of evolutionary computation (EC). In recent years, the expansion of the Internet, other telecommunications technologies, and other large scale networks have led to a world where large numbers of semi-autonomous software entities (i.e., agents) will be interacting in an open, universal system. This development cast the importance of Holland's legacy in a new light. This paper argues that Holland's fundamental arguments, and the years of developments that have followed, have a direct impact on systems of general network agents, regardless of whether they explicitly exploit EC. However, it also argues that the techniques and theories of EC cannot be directly transferred to the world of general agents (rather than EC-specific) without examination of effects that are embodied in general software agents. This paper introduces a framework for EC interchanges between general-purpose software agents. Preliminary results are shown that illustrate the EC effects of asynchronous actions of agents within this framework. Building on this framework, coevolutionary agents that interact in a simulated producer/consumer economy are introduced. Using these preliminary results as illustrations, areas for future investigation of embodied EC software agents are discussed.
TAANACH UND MEGIDDO: ÜBERLEGUNGEN ZUR STRUKTURELL-HISTORISCHEN SITUATION ZWISCHEN SAUL UND SALOMO
Authors: Niemann Hermann Michael
Published: July 2002

The article proposes a connection between Jdg. v 19 and 1 Kings iv 12 in time, situation, and behavioral pattern. If the core of the song of Deborah including Jdg. v 19 stems from the time of Saul and Eshbaal, one might identify the same behavioral pattern which I found behind 1 Kings iv 8-17 also in Jdg. v 19, viz. a carefully planned first stage of exercising influence to the northern tribal areas primarily controlled by these rulers. Using this modus operandi Solomon and later the Omrides and the Nimsides? followed previously established patterns of power and control from the times of Saul and Eshbaal.
TWO NEW SPECIES AND A NEW RECORD OF SPIDER CRABS WITH A NOTE ON STILBOGNATHUS CURVICORNIS (HERBST, 1803) FROM PAKISTAN WATERS OF THE NORTHERN ARABIAN SEA
Authors: Tirmizi Nasima , Kazmi Quddusi
Published: July 2002

Tirmizi & Kazmi (1988) reported sixteen majid crabs from Pakistan, later two more species were added (Kazmi & Tirmizi, 1995). In the present paper one species, Menaethiops nodulosus (Nobili), is being recorded for the first time from Pakistan and two species, Menaethiops gadaniensis and Pseudomicippe griffini, are being described as new. Pseudomicippe here presents the first record of the genus for this region. A note is also added on live specimens of Stilbognathus curvicornis (Herbst) previously reported from Pakistan from a dry piece of carapace only. Tirmizi & Kazmi (1988) ont signale du Pakistan seize especes de crabes Majidae, auxquelles se sont ajoutees deux especes supplementaires (Kazmi & Tirmizi, 1995). Dans le present article une espece, Menaethiops nodulosus (Nobili), est signalee pour la premiere fois de Pakistan et deux especes, Menaethiops gadaniensis et Pseudomicippe griffini, sont decrites comme nouvelles. C'est la premiere mention du genre Pseudomicippe dans la region. Une note est aussi ajoutee sur des specimens vivants de Stilbognathus curvicornis (Herbst), espece qui avait ete precedemment signalee de Pakistan seulement d'apres un fragment sec de carapace.
Root-knot nematode perineal pattern development: a reconsideration
Authors: Karssen Gerrit , Van Aelst Adriaan
Published: July 2002

The perineal pattern, a unique and complex structure located at the female posterior body region, comprises the vulva-anus area, tail terminus, phasmids, lateral lines and surrounding cuticular striae. Little is known about the development of this important but variable character complex. Published information together with scanning electron and light microscopical observations on female development and perineal patterns were used to explain in detail the perineal pattern. The basic pattern, with fine striae, is formed just after the last moult when the vulva is induced above the anus at the posterior ventral body side. This process is likely to be influenced by the previous feeding stage. The vulva-anus region moves posteriorly, while the female is still enclosed by the old cuticle layers. After resuming feeding, the female diameter increases rapidly and pattern striae become folded and coarser. The role of the expanding rectal glands and perineal pattern structures as lateral lines, anus, tail terminus and punctations are discussed in detail. Major origins for pattern variation are developmental and aging factors in both feeding stages, a vulva-anus shift and the observation of patterns of different age, in combination with variable interpretation and description.
Influence of clay minerals and exchangeable cations on the formation of humic-like substances (melanoidins) from D-glucose and L-tyrosine
Authors: Arfaioli P. , Pantani O. L. , Bosetto M. , Ristori G. G.
Published: July 2002

The ability to produce humic-like polymeric compounds, with D-glucose and L-tyrosine as starting materials, was evaluated in different mineral systems: (1) Ca-, Al- and Cu(II)-saturated montmorillonite; (2) Ca-, Al- and Cu(II)-saturated kaolinite; (3) quartz in the presence of two different amounts of the same cations (according to the cation exchange capacity of the clays); and (4) untreated quartz (as control). All systems proved to be effective in the formation of humic-like compounds, particularly quartz, in the presence of cations. The effectiveness in promoting humification reactions was strictly related to the amounts of added cations. In the reaction conditions considered, the humification appears to be due more to the cations than to the type of clay minerals. The clayey systems synthesized more complex (aromatic) substances than the quartz ones.
Mn-Mg disordering in cummingtonite: a high-temperature neutron powder diffraction study
Authors: Reece J. J. , Redfern S. A. T. , Welch M. D. , Henderson C. M. B.
Published: July 2002

The crystal structure of a manganoan cummingtonite, composition [M4](Na0.13Ca0.41Mg0.46Mn1.00) [M1,2,3](Mg4.87Mn0.13)(Si8O22)(OH)2, (Z = 2), a = 9.5539(2) Å, b = 18.0293(3) Å, c = 5.2999(1) Å, β = 102.614(2)° from Talcville, New York, has been refined at high temperature using in situ neutron powder diffraction. The P21/m to C2/m phase transition, observed as spontaneous strains +ε1 = −ε2, occurs at ˜107°C. Long-range disordering between Mg2+ and Mn2+ on the M(4) and M(2) sites occurs above 550°C. Mn2+ occupies the M(4) and M(2) sites preferring M(4) with a site-preference energy of 24.6±1.5 kJ mol−1. Disordering induces an increase in XMnM2 and decrease in XMnM4 at elevated temperatures. Upon cooling, the ordered states of cation occupancy are ‘frozen in’ and strains in lattice parameters are maintained, suggesting that re-equilibration during cooling has not taken place.
Revisions to the Declaration of Helsinki on Its 60th Anniversary
Authors: Resneck Jack S.
Published: October 2024

This Viewpoint discusses the 2024 revisions made to the Declaration of Helsinki as it continues to work toward ensuring research is subject to ethical standards that promote respect for all human participants and protect their rights and interests.
Revisiting the Declaration of Helsinki—A Patient-Centered Perspective
Authors: Bloom Lara
Published: October 2024

This Viewpoint contextualizes the history of the Declaration of Helsinki, analyzes the implications of its latest revision, and emphasizes the need for patient-centricity in research ethics.
Declaration of Helsinki—Revisions for the 21st Century
Authors: Bierer Barbara E.
Published: October 2024

This Viewpoint discusses significant revisions in the Declaration of Helsinki in response to changing ethical norms and technologies.
Understanding the Role of Organic Hole Transport Layers on Pinhole Blocking and Performance Improvement in Sb2Se3 Solar Cells
Authors: Shalvey Thomas P. , Don Christopher H. , Bowen Leon , Veal Tim D. , Major Jonathan D.
Published: October 2024

Sb2Se3 is an emerging semiconductor which has shown promise for low‐cost photovoltaic applications. After successive record‐efficiencies using a range of device structures, spiro‐OMeTAD has emerged as the default hole transport material (HTM), however, the function of HTM layers remains poorly understood. Here, thin‐film Sb2Se3 solar cells are fabricated with which three organic HTM layers ‐ namely P3HT, PCDTBT, and spiro‐OMeTAD are investigated. By comparing these against one another, and to a reference device, their role in the device stack are clarified. These organic HTM layers are found to serve a dual purpose, increasing both the average and peak efficiency by simultaneously blocking pinholes and improving the band alignment at the back contact, with marginal differences in performance between the different HTMs. This produced a champion device of 7.44% using P3HT, resulting from an improvement in all performance parameters. A more complex processing route, run‐to‐run variability, and lower overall device performance compared to the other organics challenge the assumption that spiro‐OMeTAD is the optimal HTM for Sb2Se3 devices. A Schottky barrier at the Au‐Sb2Se3 contact despite the deep work function of gold implies Fermi level pinning due to a defective interface, which each of the organic HTMs are equally capable of alleviating.
Optimal scheduling of boiler electrification for process decarbonization
Authors: Lee Jui‐Yuan , Foo Dominic C. Y. , Chen Cheng‐Liang , Tan Raymond R.
Published: October 2024

Process heat electrification offers the prospect of deep decarbonization of the chemical and allied industries. Replacing fossil fuel‐fired boilers with electric units can reduce carbon emissions if the power mix has a large share of renewables. For multinational firms with plants in multiple locations, the electrification decisions should be scheduled based on grid carbon intensity projections and should also be coordinated among these subsidiaries. In addition, carbon credits can be traded among the multiple sites to allow lagging plants to reduce their carbon footprints. A novel mathematical model has been developed to optimize process heat electrification plans in multinational corporations. The model determines the optimal timing of electrification at each location, and also the necessary level of carbon trading among subsidiaries. An illustrative case study demonstrates how the model can be used to generate electrification plans that are superior to those based on simple heuristics.
Weighing the risks and benefits of flowering early in the spring for the woody perennial Prunus pumila
Authors: Lake Diver Danielle A. , Savage Jessica A.
Published: October 2024

Premise

There are advantages to flowering early in the spring, including greater pollinator fidelity and longer fruit maturation time. But plant phenology has advanced in recent years, making many plants vulnerable to freezing damage from late frosts.

Methods

To determine the costs and benefits of flowering early in the growing season, we exposed Prunus pumila plants to two freezing treatments and a delayed flowering treatment in subsequent years. Data were collected on ovary swelling, fruit production, and pollinator visitation on hand‐ and open‐pollinated plants in all treatments. We also measured tissue damage after freeze events.

Results

Our results suggest that flowering time and temperature affect reproductive success, with fewer fruits produced after hard freezes. The same was not true for light freezes, which had minimal impact on reproduction. Freezing damage to plants after a hard freeze did affect the number of dipteran pollinators but not the overall pollinator visitation rate. Despite the clear impact of freezing temperatures on plant reproduction, flowering early provided an advantage in that reproductive output decreased with delayed flowering.

Conclusions

Our findings suggest that Prunus pumila will retain the ability to attract pollinators and produce viable seeds if exposed to false spring conditions that involve a light freeze, but hard freezes may reduce yield by an order of magnitude. Although the advantages to flowering early may outweigh the risk of freezing damage under current conditions, it is possible that flower viability may be constrained under continued climate warming.
Palladium‐Catalyzed Dehydrogenation Cross‐Coupling Reactions of Hydrosilanes: Facile Synthesis of Silanols and Silyl Ethers
Authors: Zhang Lianji , Wu Yujuan , Wang Cuiping , Zhao Yuhui , Wei Wanguo , Zhang Zhiqiang
Published: October 2024

A palladium‐catalyzed dehydrogenative cross‐coupling reactions between silanes and oxygen‐containing functional groups (water, alcohols, phenols) to generate the corresponding silanols, monosilane ethers, and disilane ethers directly in moderate to high yields. This strategy does not rely on any additional oxidizing agents or proton reductants. The possible mechanisms for this transformation are also proposed.
Fighting Amyotrophic Lateral Sclerosis by Protecting the Liver? A Prospective Cohort Study
Authors: Zhu Luyi , Li Yaojia , Yu Xinyue , Chen Yinuo , Zhang Junwei , Pang Chunyang , Xie Jiali , Gao Lingfei , Du Lihuai , Cao Wen , Fan Dongsheng , Cui Can , Yu Huan , Deng Binbin
Published: October 2024

Background

Previous studies have observed liver abnormalities in amyotrophic lateral sclerosis (ALS) patients. This study aimed to investigate whether early signs of liver disease, measured by magnetic resonance imaging‐derived iron‐corrected T1‐mapping (cT1), are risk factors for developing ALS.

Methods

cT1 and proton density fat fraction were measured and automatically analyzed using LiverMultiScan® software. The Fibrosis‐4 index was calculated using an established formula based on age and blood markers. Cox proportional hazard models were used to examine the relationship between liver disease, liver biomarkers, and incident ALS.

Results

In a cohort of 533,707 individuals from UK Biobank, 24 ALS cases were identified among 28,328 participants with liver disease during the follow‐up period. Among a total of 33,959 individuals with complete liver imaging data, 15 incident ALS cases were observed during a median follow‐up period of 5.6 years. Individuals with liver disease had a higher risk of developing ALS, with an adjusted hazard ratio of 7.35 (95% CI 4.47–12.09; p < 0.001). An increase in cT1 was also associated with a higher risk of ALS. After adjusting for age, sex, Townsend deprivation index, smoking status, alcohol intake frequency, body mass index, proton density fat fraction, Fibrosis‐4, and metabolic syndrome, an increase in cT1 remained significantly associated with a higher risk of ALS, with an adjusted hazard ratio of 3.15 (95% CI 1.79–5.55) per 1‐SD increase. Sensitivity analyses confirmed these robust results.

Interpretation

Liver disease activity, indicated by cT1, increases the risk of developing ALS, independent of metabolic syndrome, liver fat, or fibrosis. ANN NEUROL 2025;97:270–280
Activation and Deactivation of Chirality Transfer in the Superbundles of Sequence‐defined Stereoisomers
Authors: Yu Zhihong , Tan Rui , Cheng Xiaoxiao , Zhang Wei , Wang Yong , Zhang Jiandong , Zhou Nianchen , Zhang Zhengbiao , Zhu Xiulin
Published: October 2024

Discrete oligomers can be used to precisely evaluate the structure–property relationship and enable unique chiroptical activities, however, the role of stereochemical sequences on chirality transfer is still unclear. Herein, we report the successful synthesis of a series of sequence‐defined chiral azobenzene (Azo) oligomers via iterative stepwise chain growth strategy. Sequence‐defined stereoisomers with one single chiral (L or D) stereocenter at the α‐position, ω‐position and middle‐ (m−) position have completely different self‐assembly dynamics. ω‐positional stereocenter can effectively command all Azo building blocks to adopt a tilted π–π stacking along the helical superbundles, exhibiting the activation of chirality transfer. However, discrete oligomers with the stereocenter at other positions can only self‐assemble into non‐helical nanowires, accompanied by the deactivation of chirality transfer.Cooperative supramolecular interactions, including the π–π interaction between Azo units, the intermolecular hydrogen bonding and steric hindrance, are intrinsic driving forces for these differentiations.
The effect of rubber and plastic mass ratio on the compatibilized ethylene propylene diene monomer/polypropylene TPV with shape memory behavior
Authors: Xu Mengmeng , Chen Liheng , Zong Chengzhong
Published: October 2024

Thermoplastic vulcanizate (TPV) with shape memory performance showed great application potential in various fields. In this work, the effect of the mass ratio of ethylene propylene diene monomer (EPDM) and polypropylene (PP) on the performance of TPV with sea island microstructure compatibilized by magnesium maleate (MgMA) and maleic anhydride (MAH) was studied. The compatibilized TPV 70/30 and TPV 60/40 obtained good shape memory property with the shape fixity ratio (Rf) and shape recovery ratio (Rr) of 87.3%, 96.7% and 91%, 86.6% respectively. Rf increased with more PP content and decreased with more EPDM content, however Rr decreased with more PP content and increased with more EPDM content. The maximum Rf of 95.4% and the maximum Rr of 100% of TPV were obtained at the EPDM/PP mass ratio of 20/80 and 80/20 respectively. The tensile strength and elongation at break of TPV increased with more PP content in the blend. The result of DMA, Fourier transform infrared (FTIR), and SEM demonstrated the compatibility effect of MgMA and MAH on EPDM and PP interface.
Improving the tensile properties of hemicellulose/polylactic acid (PLA) blends prepared by solvent casting
Authors: Fialho Michaella Socorro Bruce , de Medeiros Souza Kataoka Lays Furtado , Ribeiro Bruno Ramos , da Luz Sandra Maria
Published: October 2024

The development of new biopolymers has been explored as an alternative to improve the biodegradability of conventional synthetic plastics, such as those used in the packaging industry. Hemicelluloses are biodegradable polymers extracted from plants that, when combined with other biodegradable polymers, such as polylactic acid (PLA), can be easily processed and satisfy the mechanical requirements for commercial application. Thus, this work seeks a biodegradable blend that combines hemicellulose and PLA properties using solvent casting. The influence of hemicellulose content (5, 10, 15, and 20 wt%) on the thermal and mechanical properties was studied. For that purpose, thermogravimetric analysis and differential scanning calorimetry were applied to determine the thermal stability and crystallinity of the materials. Additionally, water uptake and mechanical tests provided information regarding the mechanical and hygroscopic behavior of the blends due to hemicellulose addition. As a result, the blends presented intermediate thermal stabilities between those of hemicellulose and PLA and increased crystallinities with hemicellulose content. The blends are more flexible and hygroscopic than PLA and more resistant than pure hemicellulose. Given the biodegradable nature of PLA and hemicellulose, these blends have the potential for application in sustainable packaging.
Improved healability for large‐sized electrical breakdown in thermosetting polythiourethane with excellent mechanical properties and electrical insulation
Authors: Zhang Zhuolin , Wu Kangning , Yang Zichao , Sui Haoran , An Dongxu , Cui Chenhui , Zhou Fusheng , Li Jianying
Published: October 2024

Replacing thermoset insulation by healable and recyclable covalent adaptable networks is a promising approach to the sustainable development of electrical and electronic devices. However, the repair performance gifted by dynamic covalent bonds always conflicts with the excellent mechanical properties gifted by stiff cross‐linked networks. In this paper, by introducing dynamic thiocarbamate bonds, polythiourethane (PTU) with excellent mechanical properties and electrical insulation comparable to commercial epoxy resins are successfully developed, which exhibit superior healability and recyclability properties. Sub‐centimeter scale electrical breakdown failures of the PTU samples could be efficiently self‐healed with a healing efficiency up to 90%, while the storage modulus and volume resistivity exceeded 2 GPa and 1016 Ω cm, respectively. Even though the electrical breakdown strength inevitably declined after multiple repair processes, PTU samples could restore their initial excellent insulation performance by simply reprocessing with the efficiency above 95%. Moreover, the efficient healability performance of large‐sized electrical breakdown failures remained after the reprocessing. These outstanding characteristics underscore the tremendous potential of PTU materials as a new generation of sustainable high voltage insulation.
Expression‐based machine learning models for predicting plant tissue identity
Authors: Palande Sourabh , Arsenault Jeremy , Basurto‐Lozada Patricia , Bleich Andrew , Brown Brianna N. I. , Buysse Sophia F. , Connors Noelle A. , Das Adhikari Sikta , Dobson Kara C. , Guerra‐Castillo Francisco Xavier , Guerrero‐Carrillo Maria F. , Harlow Sophia , Herrera‐Orozco Héctor , Hightower Asia T. , Izquierdo Paulo , Jacobs MacKenzie , Johnson Nicholas A. , Leuenberger Wendy , Lopez‐Hernandez Alessandro , Luckie‐Duque Alicia , Martínez‐Avila Camila , Mendoza‐Galindo Eddy J. , Plancarte David Cruz , Schuster Jenny M. , Shomer Harry , Sitar Sidney C. , Steensma Anne K. , Thomson Joanne Elise , Villaseñor‐Amador Damián , Waterman Robin , Webster Brandon M. , Whyte Madison , Zorilla‐Azcué Sofía , Montgomery Beronda L. , Husbands Aman Y. , Krishnan Arjun , Percival Sarah , Munch Elizabeth , VanBuren Robert , Chitwood Daniel H. , Rougon‐Cardoso Alejandra
Published: October 2024

Premise

The selection of Arabidopsis as a model organism played a pivotal role in advancing genomic science. The competing frameworks to select an agricultural‐ or ecological‐based model species were rejected, in favor of building knowledge in a species that would facilitate genome‐enabled research.

Methods

Here, we examine the ability of models based on Arabidopsis gene expression data to predict tissue identity in other flowering plants. Comparing different machine learning algorithms, models trained and tested on Arabidopsis data achieved near perfect precision and recall values, whereas when tissue identity is predicted across the flowering plants using models trained on Arabidopsis data, precision values range from 0.69 to 0.74 and recall from 0.54 to 0.64.

Results

The identity of belowground tissue can be predicted more accurately than other tissue types, and the ability to predict tissue identity is not correlated with phylogenetic distance from Arabidopsis. k‐nearest neighbors is the most successful algorithm, suggesting that gene expression signatures, rather than marker genes, are more valuable to create models for tissue and cell type prediction in plants.

Discussion

Our data‐driven results highlight that the assertion that knowledge from Arabidopsis is translatable to other plants is not always true. Considering the current landscape of abundant sequencing data, we should reevaluate the scientific emphasis on Arabidopsis and prioritize plant diversity.
Reconfigurable Photonic Lattices Based on Atomic Coherence
Authors: Yuan Jiaqi , Liang Shun , Yu Qingsong , Li Changbiao , Zhang Yanpeng , Xiao Min , Zhang Zhaoyang
Published: October 2024

The array of coupled optical waveguides, which is also viewed as a photonic lattice, can exhibit abundant photonic band structures depending on the desired spatial arrangements of involved waveguides. Studies of photonic lattices are usually performed in solid‐state materials, where the required periodic susceptibilities can be achieved by employing the femtosecond laser direct‐writing or optical induction method, and have spawned flourishing achievements in manipulating the behaviors of light. Recently, the concept of electromagnetically induced photonic lattice (EIPL) is proposed under the well‐known electromagnetically induced transparency (EIT) in coherently prepared multilevel alkali‐metal atomic systems, where the strong coupling beams producing EIT possess spatially periodic intensity profiles. The inherited instantaneous tunability of susceptibility from EIT‐modulated atomic coherence allows for the easy reconfigurability of EIPLs, which gives rise to exotic beam dynamics under such a readily controllable framework. This paper summarizes the historical overview and recent advances of the in situ and all‐optically reconfigurable EIPLs. The Introduction section provides the scheme and formation of the EIPL via atomic coherence. The following sections review the recently demonstrated dynamical properties of light in various 1D and 2D EIPLs and in compound EIPLs built by two coupling fields. The final section gives brief concluding remarks.
Enhancing exam question quality in medical education through bootstrapping
Authors: Mohiyeddini Changiz
Published: October 2024

Medical schools are required to assess and evaluate their curricula and to develop exam questions with strong reliability and validity evidence, often based on data derived from statistically small samples of medical students. Achieving a large enough sample to reliably and validly evaluate courses, assessments, and exam questions would require extensive data collection over many years, which is inefficient, especially in the fast‐changing educational environment of medical schools. This article demonstrates how advanced quantitative methods, such as bootstrapping, can provide reliable data by resampling a single dataset to create many simulated samples. This economic approach, among others, allows for the creation of confidence intervals and, consequently, the accurate evaluation of exam questions as well as broader course and curriculum assessments. Bootstrapping offers a robust alternative to traditional methods, improving the psychometric quality of exam questions, and contributing to fair and valid assessments in medical education.
Water hyacinth biorefinery: Improved biofuel production using Trichoderma atroviride pretreatment
Authors: Ilo Obianuju P. , Simatele Mulala D.
Published: October 2024

The pyrolysis of water hyacinth is gaining attention and acceptance as a resource recovery technique due to its availability and economic viability. However, the presence of lignin, one of the three major biomass fractions, presents significant challenges for profitable water hyacinth processing for biofuel production. Fungal pretreatment of water hyacinth for lignin breakdown has been explored but the application of Trichoderma atroviride as a pretreatment for pyrolysis is relatively novel. The efficacy of T. atroviride pretreatment in improving water hyacinth's pyrolytic products using a fixed‐bed reactor was therefore investigated in this study. The optimization process was studied using a central composite design in response surface methodology with Design Expert 13. Delignification of the biomass was established because the elemental analysis showed a 25.42% increase in cellulose content and a 23.40% and 3.37% decrease in lignin and hemicellulose content, respectively. The biomass pretreatment applied influenced the physical and chemical characteristics of the pyrolytic products. The highest pyrolysis oil yield increased by 25.81% at 575 °C and particle size 2290 μm, and the highest char yield decreased by 4.23% at 273 °C and particle size 1500 μm. This research is crucial for policy and research conversations as it offers a scientific basis for the application of T. atroviride pretreatment in biomass pyrolysis technology and emphasizes the optimal utilization of water hyacinths to obtain socio‐environmental benefits.
Factors affecting generative artificial intelligence, such as ChatGPT, use in higher education: An application of technology acceptance model
Authors: Shahzad Muhammad Farrukh , Xu Shuo , Asif Muhammad
Published: October 2024

The adoption of generative artificial intelligence (GAI) tools, such as ChatGPT, in higher education presents numerous opportunities and challenges. The use of GAI technologies in various fields, including education, has accelerated as technology develops. The widely used language model ChatGPT, developed by OpenAI, has become progressively more important, especially in the field of education. This study employs the technology acceptance model to investigate the factors influencing the employment of ChatGPT within the higher education sector of Pakistan. This study employed the PLS‐SEM method for probing data collected from 368 Pakistani university students. The findings indicate that ChatGPT trust positively mediates the affiliation between ChatGPT self‐efficacy, ChatGPT actual use, ChatGPT use for information and ChatGPT use for interaction. Further, ChatGPT usefulness and ChatGPT ease of use significantly moderate the association between ChatGPT self‐efficacy and ChatGPT trust. Educators must encourage students to use ChatGPT safely to preserve their critical thinking, problem‐solving abilities and creativity during assessments. This study contributes to understanding generative AI tools such as ChatGPT that are used in educational settings and provides insights for administrators and policymakers aiming to implement these technologies effectively.
Analysis of the Plasticity of Circulating Tumor Cells Reveals Differentially Regulated Kinases During the Suspension‐to‐Adherent Transition
Authors: Smit Daniel J. , Hoffer Konstantin , Bettin Bettina , Kriegs Malte , Cayrefourcq Laure , Schumacher Udo , Pantel Klaus , Alix‐Panabières Catherine , Jücker Manfred
Published: October 2024

Background

Research on circulating tumor cells (CTCs) offers the opportunity to better understand the initial steps of blood‐borne metastasis as main cause of cancer‐related deaths. Here, we have used the colon cancer CTC‐MCC‐41 and breast cancer CTC‐ITB‐01 lines, which were both established from human CTCs as permanent cell lines as models to further study CTC biology with special emphasis on anchorage‐independent survival and growth.

Methods and Results

Both cell lines showed a marked intrinsic plasticity to switch between suspension and adherent in vitro growth, in 2D adherent culture conditions, and established an equilibrium of both growth patterns with predominant adherent cells in the CTC‐MCC‐41 line (77%) and suspension cells in the CTC‐ITB‐01 line (85%). Western blot analysis revealed a higher expression of pERK1/2 in CTC‐ITB‐01 adherent cells compared to the suspension counterpart that suggested the involvement of kinases in this process. Subsequent functional kinome profiling identified several serine/threonine as well as tyrosine kinases that were differentially regulated in adherent and suspension CTCs. In the adherent cells of the breast cancer line CTC‐ITB‐01 the activity of MSK1, Src family kinases and the PKG family was increased compared to the suspension counterpart. In adherent cells of the colorectal CTC‐MCC‐41 line, an increased activity of TYRO3 and JAK2 was detected, whereas p38 MAPK was strongly impaired in the suspension CTC‐MCC‐41 cells. Some of the regulated kinases, which include the Src family, TYRO3, MSK1, JAK2 and p38 MAPK, have been associated with crucial cellular processes including proliferation, migration and dormancy in the past.

Conclusions

The investigated CTC lines exhibit a high plasticity, similar to the concept of ‘adherent‐to‐suspension transition (AST)’ that was recently suggested as a new hallmark of tumor biology by Huh et al. Moreover, we identified differentially regulated kinome profiles that may represent potential targets for future studies on therapeutic interventions.