bluuebunny/crossref_metadata_2025 huggingface dataset:
Bacterial gasdermins reveal an ancient mechanism of cell death
Authors: Johnson Alex G. , Wein Tanita , Mayer Megan L. , Duncan-Lowey Brianna , Yirmiya Erez , Oppenheimer-Shaanan Yaara , Amitai Gil , Sorek Rotem , Kranzusch Philip J.
Published: January 2022

Ancient origin of cell death

Gasdermins are cell death proteins in mammals that form membrane pores in response to pathogen infection. Johnson
et al
. report that diverse bacteria encode structural and functional homologs of mammalian gasdermins. Like their mammalian counterparts, bacterial gasdermins are activated by caspase-like proteases, oligomerize into large membrane pores, and defend against pathogen—in this case, bacteriophage—infection. Proteolytic activation occurs through the release of a short inhibitory peptide, and many bacterial gasdermins are lipidated to facilitate membrane pore formation. Pyroptotic cell death, a central component of mammalian innate immunity, thus has a shared origin with an ancient antibacteriophage defense system. —SMH
Fetal bovine serum—a cell culture dilemma
Authors: van der Valk Jan
Published: January 2022

Ethical and possible reproducibility issues arise when using fetal bovine serum in cell culture media
Tumors resurrect an embryonic vascular program to escape immunity
Authors: Huijbers Elisabeth J. M. , Khan Kabir A. , Kerbel Robert S. , Griffioen Arjan W.
Published: January 2022

Tumors escape immunity by using embryonic-like angiogenesis resulting in nonadhesive vasculature, preventing leukocyte infiltration.
Recombinant HNP-1 Produced by Escherichia coli Triggers Bacterial Apoptosis and Exhibits Antibacterial Activity against Drug-Resistant Bacteria
Authors: Xie Qi , Wang Yin , Zhang Mengmeng , Wu Shujia , Wei Wei , Xiao Weidi , Wang Yihao , Zhao Jinchao , Liu Nan , Jin Yiguang , Wu Junzhu , Xu Ping
Published: January 2022

Human neutrophil peptide-1 (HNP-1) is a promising antibiotic candidate, but its clinical application has been hampered by the difficulty of mass production and an inadequate understanding of its bactericidal mechanisms. In this study, we demonstrated that recombinant protein expression combined with ultrafiltration may be a simple and cost-effective solution to HNP-1 production.
Protein Interactome Analysis of the Type IX Secretion System Identifies PorW as the Missing Link between the PorK/N Ring Complex and the Sov Translocon
Authors: Gorasia Dhana G. , Lunar Silva Ignacio , Butler Catherine A. , Chabalier Maïalène , Doan Thierry , Cascales Eric , Veith Paul D. , Reynolds Eric C.
Published: January 2022

The T9SS is a newly identified protein secretion system of the
Fibrobacteres
-
Chlorobi
-
Bacteroidetes
superphylum used by pathogens associated with diseases of humans, fish, and poultry for the secretion and cell surface attachment of virulence factors. The T9SS comprises three known modules: (i) the trans-envelope core module comprising the PorL/M motor and the PorK/N ring, (ii) the outer membrane Sov translocon, and (iii) the cell surface attachment complex.
erm
(T)-Mediated Macrolide-Lincosamide Resistance in Streptococcus suis
Authors: Yu Rui , Xu Yindi , Schwarz Stefan , Shang Yanhong , Yuan Xuezhen , Zhang Yue , Li Dexi , Du Xiang-Dang
Published: January 2022

Macrolide and lincosamide resistance due to the presence of
erm
(T) have posed a challenge for the treatment of Gram-positive pathogens. Because of the low detection rate of
erm
(T) gene among the
S. suis
population due to the fitness cost of the
erm
(T)-carrying plasmid and ICE, the presence of
erm
(T) in
S. suis
and its potential transmission to other Gram-positive pathogens will be of important significance.
Outbreak of NDM-1-Producing Escherichia coli in a Coronavirus Disease 2019 Intensive Care Unit in a Mexican Tertiary Care Center
Authors: Fernández-García Oscar A. , González-Lara María F. , Villanueva-Reza Marco , de-León-Cividanes Nereyda , Xancal-Salvador Luis F. , Esteban-Kenel Verónica , Cárdenas-Ochoa Ayleen , Cervantes-Sánchez Axel , Martínez-Gamboa Areli , Ochoa-Hein Eric , Galindo-Fraga Arturo , Bobadilla-del-Valle Miriam , Sifuentes-Osornio José , Ponce-de-León Alfredo
Published: January 2022

The SARS-CoV-2 pandemic has resulted in a surge of critically ill patients. Hospitals have had to adapt to the demand by repurposing areas as intensive care units. This has resulted in high workload and disruption of usual hospital workflows. Surge capacity guidelines and pandemic response plans do not contemplate how to limit collateral damage from issues like hospital-acquired infections. It is vital to ensure quality of care in surge scenarios.
Behaviour model integrated by protection motivation theory and information–motivation–behavioural skills model applying in pregnancy weight management (PrInMAMa): a study protocol for a randomised controlled trial in China
Authors: Ge Jinjin , Wang Li , Peng Xueqing , Zhang Chi , Zhao Shiqi , Zhou Meng , Tang Shaowen , You Hua
Published: January 2022

Introduction

Excessive gestational weight gain poses a significant threat to maternal and child health. The healthy behaviour theory has been increasingly applied to weight management during pregnancy, but research is still insufficient. The successful application of the protection motivation theory (PMT) and the information–motivation–behavioural skills (IMB) model in the field of healthy behaviour laid the foundation for this intervention study. The overall aim of this study is to test the effectiveness of interventions based on the behaviour model integrated with the PMT and IMB model (PMT–IMB model) on weight management and provide feasible methods for weight management during pregnancy.

Methods and analysis

This prospective, single-centre, randomised controlled trial involves two steps. First, based on the PMT–IMB model, evaluation tools and intervention materials will be developed. Second, more than 800 women in the first trimester of pregnancy will be randomly assigned to two groups and will be followed until 1 week after delivery. The control group will receive standardised antenatal care (ANC), whereas the experimental group will receive both standardised ANC and interventions based on the PMT–IMB model. After three surveys (at enrolment, at 28 weeks of gestation, and on the day of hospitalisation for delivery), primary outcomes (scores of the subscales of the PMT–IMB model, scores of the pregnancy weight management strategy scale, and gestational weight gain) and secondary outcomes (pregnancy outcomes and pregnancy complications) will be obtained. Differences in outcomes between the two groups will be analysed to evaluate the effectiveness of the intervention.

Ethics and dissemination

The study protocol has been approved by the ethics committee of Nanjing Medical University. All participants will sign an informed consent form prior to enrolment. The findings of the study will be published in peer-reviewed journals and presented at conferences.

Trial registration number

ChiCTR2100043231
Neoadjuvant programmed cell death 1 blockade combined with chemotherapy for resectable esophageal squamous cell carcinoma
Authors: Yang Weixiong , Xing Xiangbin , Yeung Sai-Ching Jim , Wang Siyu , Chen Wenfang , Bao Yong , Wang Fang , Feng Shiting , Peng Fang , Wang Xiaoyan , Chen Shuling , He Minghui , Zhang Ning , Wang Honglei , Zeng Bo , Liu Zhenguo , Kidane Biniam , Seder Christopher W , Koyanagi Kazuo , Shargall Yaron , Luo Honghe , Peng Sui , Cheng Chao
Published: January 2022

Background

Programmed cell death 1 (PD-1) blockade induces tumor regression in patients with advanced esophageal squamous cell carcinoma (ESCC); however, little is known about the efficacy of PD-1 blockade as neoadjuvant therapy in resectable ESCC. We aim to assess the safety and feasibility of using the combination of neoadjuvant PD-1 blockade with chemotherapy in patients with ESCC.

Methods

Patients with previously untreated, resectable (stage II or III) ESCC were enrolled. Each patient received two 21-day cycles of neoadjuvant treatment with camrelizumab, nab-paclitaxel, and carboplatin before undergoing surgical resection approximately 6–9 weeks after the first cycle.

Results

Between January 2020 and September 2020, 37 patients were screened, of whom 23 were enrolled. The neoadjuvant therapeutic regimen had an acceptable side effect profile, and no delays in surgery were observed. Severe (grade 3–4) treatment-related adverse events included neutropenia (9 of 23, 39.1%) and leukopenia (2 of 23, 8.7%). The objective response and disease control rates were 90.5% and 100%, respectively. Twenty patients received surgery, and R0 resection was achieved in all cases. Five (25%) patients had a pathological complete response (PCR) and 10 (50%) patients had a major pathological response. The proportion of patients with a high tumor mutation burden and a high expression of programmed death-ligand 1 (PD-L1) in primary tumor was significantly higher in the PCR group than in the non-PCR group (p=0.044). The number of infiltrating PD-L1+ CD163+ cells was significantly lower in the PCR group than in the non-PCR group after treatment (p=0.017).

Conclusions

Neoadjuvant camrelizumab plus carboplatin and nab-paclitaxel had manageable treatment-related adverse effects and induced an objective response in 90.5% of patients, demonstrating its antitumor efficacy in resectable ESCC.

Trial registration number

ChiCTR2000028900.
Moral injury and well-being in essential workers during the COVID-19 pandemic: local survey findings
Authors: Guy Catherine , Kunonga Edward , Kennedy Angela , Patel Paras
Published: January 2022

Background

Essential workers have faced many difficult situations working during the pandemic. Staff may feel that they, or other people, have acted wrongly and be distressed by this. This represents moral injury, which has been linked with significant mental ill health.

Methods

This survey asked essential workers in County Durham and Darlington about their experiences during the first wave of the pandemic and anything they felt would help. Well-being and moral injury were rated using sliders.

Results

There were 566 responses. A majority of respondents reported feeling troubled by other people’s actions they felt were wrong (60% scored over 40, where 0 is ‘not at all troubled’ and 100 ‘very troubled’, median score=52.5). Respondents were generally less troubled by their own actions (median score=3). Well-being and moral injury scores varied by employment sector (eg, National Health Service (NHS) staff were more troubled by the actions of others than non-NHS staff).

Staff suggestions included regular supervisor check-ins, ensuring kindness from everyone, fair rules and enforcement and improving communication and processes. Respondents offered simple, practical actions that could be taken by leaders at team, organisation, societal and governmental levels to tackle moral injury and the underlying causes of moral injurious environments.

Conclusion

Using these findings to develop a strategy to address moral injury is important, not only for staff well-being, but staff retention and continued delivery of vital services in these challenging times. Working together, we can seek to reduce and mitigate ‘moral injury’ the same way we do for other physical workplace ‘injuries’.
A Facile Microwave-Assisted Green Synthetic Approach of Solid-State Fluorescent Carbon-Dot Nanopowders Derived from Biowaste for Potential Latent-Fingerprint Enhancement
Authors: Dinake Pogisego , Phokedi Gothatamang Norma , Mokgadi Janes , Ntshekisang Anthony , Botlhomilwe Mmamiki Ayanda , Kelebemang Rosemary , Motswetla Obakeng , Present Bokang
Published: January 2022

Latent fingerprint detection and visualization remains a challenge especially where problems of poor contrast, auto-fluorescent surfaces and patterned backgrounds are encountered. As a result there is an increasing interest in the development of simple, cost effective, rapid and yet accurate methods for latent fingerprint detection and recovery. Herein, this paper reports the synthesis of bright blue photoluminescent carbon dots (C-dots) via an eco-friendly and simple one-step microwave-assisted carbonization of potato peels’ biomass. The C-dots were prepared in only 3 min and ground into powder and used without any further treatment. The as-prepared C-dots were characterized using atomic force microscope, Fourier transform infra-red spectroscopy and X-ray diffraction with an average size of 1.0[Formula: see text]nm. The optical properties of the as-prepared C-dots were studied by UV-Vis spectroscopy and spectrofluorometer which established an excitation and emission wavelengths of 390[Formula: see text]nm and 480[Formula: see text]nm, respectively. Owing to their strong solid state fluorescence, the as-prepared C-dots’ powder was successfully used in latent fingerprint detection and imaging on porous and nonporous surfaces. Latent fingerprints were recovered with high resolution and excellent quality providing sufficient details for individual identification. These findings demonstrate that C-dots derived from biomass have a great potential in latent fingerprint analysis for forensic applications.
Fluvial processes and landforms
Authors: Ferguson Robert I. , Lewin John , Hardy Richard J.
Published: January 2022

The period 1965–2000 saw a sustained increase in research and publications on fluvial processes and landforms. The trend towards generalization and/or mechanistic understanding, rather than site-specific history, continued. Research was multidisciplinary, with important contributions from hydraulic engineers, geologists and physical geographers and from experimental and theoretical approaches as well as geomorphological and sedimentological fieldwork. Rapidly increasing computer power underpinned new measurement methods, and greatly increased the scope of data analysis and numerical modelling. There were major advances in understanding the interaction of river process and form at reach scale, with growing recognition of differences between sand-bed and coarse-bed rivers. Field studies outside Europe and North America led to greater awareness of the diversity of river planforms and depositional landforms. Conceptual models of how rivers respond to natural or anthropogenic change in boundary conditions at different timescales were refined, taking advantage of studies of the response to land-use change, major floods and volcanic eruptions. The dating of sediments allowed greater appreciation of fluctuations in the incidence of extreme driving events over centuries and thousands of years. Towards the end of this period, research on bedrock rivers began to take off.
Cross-border petroleum geology in the North Sea: an introduction
Authors: Archer Stuart G. , Kombrink Henk , Patruno Stefano , Chiarella Domenico , Jackson Christopher A.-L. , Howell John A.
Published: January 2022

The North Sea has reached an ultra-mature state as a petroleum basin, entering a phase of infrastructure-led exploration in an attempt to extend the economic lives of the main fields and reduce the rate of production decline. At the same time, the transition to a future low-carbon use of the basin is also in progress. As the papers in this volume demonstrate, in order to find, appraise and develop the mostly smaller near-field opportunities as well as making sure to grasp the opportunities of the near-future energy transition, a regional understanding of the North Sea is still critical. Even more so, a cross-border approach is essential because: (1) some of the plays currently being targeted have a clear cross-border element; (2) it allows a comparison of stratigraphic names throughout the entire basin; and (3) it enables explorers to learn lessons from one part of the rift to be applied somewhere else.

This volume offers an up-to-date ‘geology-without-borders’ view of the stratigraphy, sedimentology, tectonics and oil-and-gas exploration trends of the entire North Sea Basin. The challenges associated with data continuity and nomenclature differences across median lines are discussed and mitigated. Examples of under-exploited cross-border plays and discoveries are discussed.
Improving the Variational Quantum Eigensolver Using Variational Adiabatic Quantum Computing
Authors: Harwood Stuart M. , Trenev Dimitar , Stober Spencer T. , Barkoutsos Panagiotis , Gujarati Tanvi P. , Mostame Sarah , Greenberg Donny
Published: January 2022

The variational quantum eigensolver (VQE) is a hybrid quantum-classical algorithm for finding the minimum eigenvalue of a Hamiltonian that involves the optimization of a parameterized quantum circuit. Since the resulting optimization problem is in general nonconvex, the method can converge to suboptimal parameter values that do not yield the minimum eigenvalue. In this work, we address this shortcoming by adopting the concept of variational adiabatic quantum computing (VAQC) as a procedure to improve VQE. In VAQC, the ground state of a continuously parameterized Hamiltonian is approximated via a parameterized quantum circuit. We discuss some basic theory of VAQC to motivate the development of a hybrid quantum-classical homotopy continuation method. The proposed method has parallels with a predictor-corrector method for numerical integration of differential equations. While there are theoretical limitations to the procedure, we see in practice that VAQC can successfully find good initial circuit parameters to initialize VQE. We demonstrate this with two examples from quantum chemistry. Through these examples, we provide empirical evidence that VAQC, combined with other techniques (an adaptive termination criteria for the classical optimizer and a variance-based resampling method for the expectation evaluation), can provide more accurate solutions than “plain” VQE, for the same amount of effort.
Seeing Colours: Addressing Colour Vision Deficiency with Vision Augmentations using Computational Glasses
Authors: Sutton Jonathan , Langlotz Tobias , Plopski Alexander
Published: January 2022

Colour vision deficiency is a common visual impairment that cannot be compensated for using optical lenses in traditional glasses, and currently remains untreatable. In our work, we report on research on Computational Glasses for compensating colour vision deficiency. While existing research only showed corrected images within the periphery or as an indirect aid, Computational Glasses build on modified standard optical see-through head-mounted displays and directly modulate the user’s vision, consequently adapting their perception of colours. In this work, we present an exhaustive literature review of colour vision deficiency compensation and subsequent findings; several prototypes with varying advantages—from well-controlled bench prototypes to less controlled but higher application portable prototypes; and a series of studies evaluating our approach starting with proving its efficacy, comparing to the state-of-the-art, and extending beyond static lab prototypes looking at real world applicability. Finally, we evaluated directions for future compensation methods for computational glasses.
The Making of Meaning through Dyadic Haptic Affective Touch
Authors: Price Sara , Bianchi-Berthouze Nadia , Jewitt Carey , Yiannoutsou Nikoleta , Fotopoulou Katerina , Dajic Svetlana , Virdee Juspreet , Zhao Yixin , Atkinson Douglas , Brudy Frederik
Published: January 2022

Despite the importance of touch in human–human relations, research in affective tactile practices is in its infancy, lacking in-depth understanding needed to inform the design of remote digital touch communication. This article reports two qualitative studies that explore tactile affective communication in specific social contexts, and the bi-directional creation, sending and interpretation of digital touch messages using a purpose-built research tool, the Tactile Emoticon. The system comprises a pair of remotely connected mitts, which enable users in different locations to communicate through tactile messages, by orchestrating duration and level of three haptic sensations: vibration, pressure and temperature. Qualitative analysis shows the nuanced ways in which 68 participants configured these elements to make meaning from touch messages they sent and received. It points to the affect and emotion of touch, its sensoriality and ambiguity, the significance of context, social norms and expectations of touch participants. Findings suggest key design considerations for digital touch communication, where the emphasis shifts from generating ‘recognizable touches’ to tools that allow people to shape their touches and establish common understanding about their meaning.
Being Correct Is Not Enough: Efficient Verification Using Robust Linear Temporal Logic
Authors: Anevlavis Tzanis , Philippe Matthew , Neider Daniel , Tabuada Paulo
Published: January 2022

While most approaches in formal methods address system correctness, ensuring robustness has remained a challenge. In this article, we present and study the logic rLTL, which provides a means to formally reason about both correctness and robustness in system design. Furthermore, we identify a large fragment of rLTL for which the verification problem can be efficiently solved, i.e., verification can be done by using an automaton, recognizing the behaviors described by the rLTL formula φ, of size at most O(3 |φ |), where |φ | is the length of φ. This result improves upon the previously known bound of O(5|φ |) for rLTL verification and is closer to the LTL bound of O(2|φ |). The usefulness of this fragment is demonstrated by a number of case studies showing its practical significance in terms of expressiveness, the ability to describe robustness, and the fine-grained information that rLTL brings to the process of system verification. Moreover, these advantages come at a low computational overhead with respect to LTL verification.
Black Lives, Green Books, and Blue Checks
Authors: Klassen Shamika , Kingsley Sara , McCall Kalyn , Weinberg Joy , Fiesler Casey
Published: January 2022

The Negro Motorist Green Book was a publication that offered resources for the Black traveler from 1936 to 1966. More than a directory of Black-friendly businesses, it also offered articles that provided insights for how best to travel safely, engagement with readers through contests and invitations for readers to share travel stories, and even civil rights advocacy. Today, a contemporary counterpart to the Green Book is Black Twitter, where people share information and advocate for their community. By conducting qualitative open coding on a subset of Green Book editions as well as tweets from Black Twitter, we explore similarities and overlapping characteristics such as safety, information sharing, and social justice. Where they diverge exposes how spaces like Black Twitter have evolved to accommodate the needs of people in the Black diaspora beyond the scope of physical travel and into digital spaces. Our research points to ways that the Black community has shifted from the physical to the digital space, expanding how it supports itself, and the potential for research to strengthen throughlines between the past and the present in order to better see the possibilities of the future.
Bridging Community, History, and Culture in Personal Informatics Tools
Authors: Martin-Hammond Aqueasha , Purnell Tanjala S.
Published: January 2022

A healthy diet and increased physical activity are essential for reducing the prevalence of cardiovascular disease and related deaths, a worldwide public health concern that disproportionately affects Black American communities. Still, Black Americans can face unique challenges meeting dietary and physical activity requirements due to inequities in access and quality of care, environmental and local factors, and difficulties in changing individual health behaviors. Personal informatics and self-tracking tools are one way of increasing awareness of health behaviors to motivate behavior change. However, there are still gaps in knowledge about what encourages different users to engage with personal informatics tools over time, particularly when used in collaborative, community-health settings. This paper contributes a nuanced understanding of fifteen participants' reasons for engaging in an existing community-based health education and behavior change program that combines collaborative self-tracking with culturally relevant content and social engagement to motivate heart-healthy behaviors. We illustrate participants' positive and negative experiences engaging in self-tracking and collaborative tasks during the program. We also discuss how participants envision that integrating technology might support or hinder participant engagement and the work of deploying community-based public health interventions. Finally, we discuss design implications for culturally informed, community-based personal informatics tools that engage Black American's in heart-healthy activities.
Designing for Engaging with News using Moral Framing towards Bridging Ideological Divides
Authors: Wang Jessica Z. , Zhang Amy X. , Karger David R.
Published: January 2022

Society is showing signs of strong ideological polarization. When pushed to seek perspectives different from their own, people often reject diverse ideas or find them unfathomable. Work has shown that framing controversial issues using the values of the audience can improve understanding of opposing views. In this paper, we present our work designing systems for addressing ideological division through educating U.S. news consumers to engage using a framework of fundamental human values known as Moral Foundations. We design and implement a series of new features that encourage users to challenge their understanding of opposing views, including annotation of moral frames in news articles, discussion of those frames via inline comments, and recommendations based on relevant moral frames. We describe two versions of features---the first covering a suite of ways to interact with moral framing in news, and the second tailored towards collaborative annotation and discussion. We conduct a field evaluation of each design iteration with 71 participants in total over a period of 6-8 days, finding evidence suggesting users learned to re-frame their discourse in moral values of the opposing side. Our work provides several design considerations for building systems to engage with moral framing.
"I Felt a Little Crazy Following a 'Doll'"
Authors: Choudhry Abhinav , Han Jinda , Xu Xiaoyu , Huang Yun
Published: January 2022

Virtual Influencers (VIs) are computer-generated characters, many of which are often visually indistinguishable from humans and interact with the world in the first-person perspective as social media influencers. They are gaining popularity by creating content in various areas, including fashion, music, art, sports, games, environmental sustainability, and mental health. Marketing firms and brands increasingly use them to capitalise on their millions of followers. Yet, little is known about what prompts people to engage with these digital beings. In this paper, we present our interview study with online users who followed different VIs on Instagram beyond the fashion application domain. Our findings show that the followers are attracted to VIs due to a unique mixture of visual appeal, sense of mystery, and creative storytelling that sets VI content apart from that of real human influencers. Specifically, VI content enables digital artists and content creators by removing the constraints of bodies and physical features. The followers not only perceived VIs' rising popularity in commercial industries, but also are supportive of VI involvement in non-commercial causes and campaigns. However, followers are reluctant to attribute trustworthiness to VIs in general though they display trust in limited domains, e.g., technology, music, games, and art. This research highlights VI's potential as innovative digital content, carrying influence and employing more varied creators, an appeal that could be harnessed by diverse industries and also by public interest organisations.
Distance Matters to Weak Ties
Authors: Yang Chi-Lan , Yamashita Naomi , Kuzuoka Hideaki , Wang Hao-Chuan , Foong Eureka
Published: January 2022

Workers tend to make inferences about one another's commitment and dedication to work depending on what cues are available to them, affecting worker relationships and collaboration outcomes. In this work, we investigate how remote work affects workers' perceptions of their colleagues with different levels of social connectivity, commonly referred to as strong ties and weak ties. When working remotely, workers' perceptions of weak ties may suffer due to the lack of in-person interaction. On the other hand, workers' inferences about their strong ties may also be impacted by losing richer communication cues, even though they had more connections with their strong ties than weak ties. This study explores how remote workers make inferences about engagement levels of and willingness to collaborate with weak ties compared to strong ties. We used a mixed-methods approach involving survey data, experience sampling, and in-depth interviews with 20 workers from different companies in Taiwan. Results showed that workers depended on one-on-one synchronous tools to infer the engagement level of strong ties but used group-based communication tools to infer the engagement level of weak ties. Interestingly, the absence of cues in remote workplaces exacerbated prior impressions formed in the physical office. Furthermore, remote work led workers to develop polarized perceptions of their respective ties. We discuss how characteristics of computer-mediated communication tools and interaction types interplay to affect workers' perceptions of remote colleagues and identify design opportunities for helping remote workers maintain awareness of weak ties.
The decidability and complexity of interleaved bidirected Dyck reachability
Authors: Kjelstrøm Adam Husted , Pavlogiannis Andreas
Published: January 2022

Dyck reachability is the standard formulation of a large domain of static analyses, as it achieves the sweet spot between precision and efficiency, and has thus been studied extensively. Interleaved Dyck reachability (denoted
D

k

⊙
D

k

) uses two Dyck languages for increased precision (e.g., context and field sensitivity) but is well-known to be undecidable. As many static analyses yield a certain type of bidirected graphs, they give rise to interleaved bidirected Dyck reachability problems. Although these problems have seen numerous applications, their decidability and complexity has largely remained open. In a recent work, Li et al. made the first steps in this direction, showing that (i)
D
1
⊙
D
1
reachability (i.e., when both Dyck languages are over a single parenthesis and act as counters) is computable in
O
(
n
7
) time, while (ii)
D

k

⊙
D

k

reachability is NP-hard. However, despite this recent progress, most natural questions about this intricate problem are open.

In this work we address the decidability and complexity of all variants of interleaved bidirected Dyck reachability. First, we show that
D
1
⊙
D
1
reachability can be computed in
O
(
n
3
· α(
n
)) time, significantly improving over the existing
O
(
n
7
) bound. Second, we show that
D

k

⊙
D
1
reachability (i.e., when one language acts as a counter) is decidable, in contrast to the non-bidirected case where decidability is open. We further consider
D

k

⊙
D
1
reachability where the counter remains linearly bounded. Our third result shows that this bounded variant can be solved in
O
(
n
2
· α(
n
)) time, while our fourth result shows that the problem has a (conditional) quadratic lower bound, and thus our upper bound is essentially optimal. Fifth, we show that full
D

k

⊙
D

k

reachability is undecidable. This improves the recent NP-hardness lower-bound, and shows that the problem is equivalent to the non-bidirected case. Our experiments on standard benchmarks show that the new algorithms are very fast in practice, offering many orders-of-magnitude speedups over previous methods.
Interval universal approximation for neural networks
Authors: Wang Zi , Albarghouthi Aws , Prakriya Gautam , Jha Somesh
Published: January 2022

To verify safety and robustness of neural networks, researchers have successfully applied
abstract interpretation
, primarily using the interval abstract domain. In this paper, we study the theoretical power and limits of the interval domain for neural-network verification.

First, we introduce the
interval universal approximation
(IUA) theorem. IUA shows that neural networks not only can approximate any continuous function
f
(universal approximation) as we have known for decades, but we can find a neural network, using any well-behaved activation function, whose interval bounds are an arbitrarily close approximation of the set semantics of
f
(the result of applying
f
to a set of inputs). We call this notion of approximation
interval approximation
. Our theorem generalizes the recent result of Baader et al. from ReLUs to a rich class of activation functions that we call
squashable functions
. Additionally, the IUA theorem implies that we can always construct provably robust neural networks under ℓ
∞
-norm using almost any practical activation function.

Second, we study the computational complexity of constructing neural networks that are amenable to precise interval analysis. This is a crucial question, as our constructive proof of IUA is exponential in the size of the approximation domain. We boil this question down to the problem of approximating the range of a neural network with squashable activation functions. We show that the range approximation problem (RA) is a Δ
2
-intermediate problem, which is strictly harder than
NP
-complete problems, assuming
coNP
⊄
NP
. As a result,
IUA is an inherently hard problem
: No matter what abstract domain or computational tools we consider to achieve interval approximation, there is no efficient construction of such a universal approximator. This implies that it is hard to construct a provably robust network, even if we have a robust network to start with.
Pirouette: higher-order typed functional choreographies
Authors: Hirsch Andrew K. , Garg Deepak
Published: January 2022

We present Pirouette, a language for typed higher-order functional choreographic programming. Pirouette offers programmers the ability to write a centralized functional program and compile it via endpoint projection into programs for each node in a distributed system. Moreover, Pirouette is defined generically over a (local) language of messages, and lifts guarantees about the message type system to its own. Message type soundness also guarantees deadlock freedom. All of our results are verified in Coq.
A relational theory of effects and coeffects
Authors: Dal Lago Ugo , Gavazzo Francesco
Published: January 2022

Graded modal types systems and coeffects are becoming a standard formalism to deal with context-dependent, usage-sensitive computations, especially when combined with computational effects. From a semantic perspective, effectful and coeffectful languages have been studied mostly by means of denotational semantics and almost nothing has been done from the point of view of relational reasoning. This gap in the literature is quite surprising, since many cornerstone results — such asnon-interference,metric preservation, andproof irrelevance— on concrete coeffects are inherently relational. In this paper, we fill this gap by developing a general theory and calculus of program relations for higher-order languages with combined effects and coeffects. The relational calculus builds upon the novel notion of acorelator(orcomonadic lax extension) to handle coeffects relationally. Inside such a calculus, we define three notions of effectful and coeffectful program refinements:contextual approximation,logical preorder, andapplicative similarity. These are the first operationally-based notions of program refinement (and, consequently, equivalence) for languages with combined effects and coeffects appearing in the literature. We show that the axiomatics of a corelator (together with the one of a relator) is precisely what is needed to prove all the aforementioned program refinements to be precongruences, this way obtaining compositional relational techniques for reasoning about combined effects and coeffects.
Type-level programming with match types
Authors: Blanvillain Olivier , Brachthäuser Jonathan Immanuel , Kjaer Maxime , Odersky Martin
Published: January 2022

Type-level programming is becoming more and more popular in the realm of functional programming. However, the combination of type-level programming and subtyping remains largely unexplored in practical programming languages. This paper presents
match types
, a type-level equivalent of pattern matching. Match types integrate seamlessly into programming languages with subtyping and, despite their simplicity, offer significant additional expressiveness. We formalize the feature of match types in a calculus based on System F sub and prove its soundness. We practically evaluate our system by implementing match types in the Scala 3 reference compiler, thus making type-level programming readily available to a broad audience of programmers.
Truly stateless, optimal dynamic partial order reduction
Authors: Kokologiannakis Michalis , Marmanis Iason , Gladstein Vladimir , Vafeiadis Viktor
Published: January 2022

Dynamic partial order reduction (DPOR) verifies concurrent programs by exploring all their interleavings up to some equivalence relation, such as the Mazurkiewicz trace equivalence. Doing so involves a complex trade-off between space and time. Existing DPOR algorithms are either exploration-optimal (i.e., explore exactly only interleaving per equivalence class) but may use exponential memory in the size of the program, or maintain polynomial memory consumption but potentially explore exponentially many redundant interleavings.

In this paper, we show that it is possible to have the best of both worlds: exploring exactly one interleaving per equivalence class with linear memory consumption. Our algorithm, TruSt, formalized in Coq, is applicable not only to sequential consistency, but also to any weak memory model that satisfies a few basic assumptions, including TSO, PSO, and RC11. In addition, TruSt is embarrassingly parallelizable: its different exploration options have no shared state, and can therefore be explored completely in parallel. Consequently, TruSt outperforms the state-of-the-art in terms of memory and/or time.
Verified tensor-program optimization via high-level scheduling rewrites
Authors: Liu Amanda , Bernstein Gilbert Louis , Chlipala Adam , Ragan-Kelley Jonathan
Published: January 2022

We present a lightweight Coq framework for optimizing tensor kernels written in a pure, functional array language. Optimizations rely on user scheduling using series of verified, semantics-preserving rewrites. Unusually for compilation targeting imperative code with arrays and nested loops, all rewrites are source-to-source within a purely functional language. Our language comprises a set of core constructs for expressing high-level computation detail and a set of what we call reshape operators, which can be derived from core constructs but trigger low-level decisions about storage patterns and ordering. We demonstrate that not only is this system capable of deriving the optimizations of existing state-of-the-art languages like Halide and generating comparably performant code, it is also able to schedule a family of useful program transformations beyond what is reachable in Halide.
Solving constrained Horn clauses modulo algebraic data types and recursive functions
Authors: K Hari Govind V , Shoham Sharon , Gurfinkel Arie
Published: January 2022

This work addresses the problem of verifying imperative programs that manipulate data structures, e.g., Rust programs. Data structures are usually modeled by Algebraic Data Types (ADTs) in verification conditions. Inductive invariants of such programs often require recursively defined functions (RDFs) to represent abstractions of data structures. From the logic perspective, this reduces to solving Constrained Horn Clauses (CHCs) modulo both ADT and RDF. The underlying logic with RDFs is undecidable. Thus, even verifying a candidate inductive invariant is undecidable. Similarly, IC3-based algorithms for solving CHCs lose their progress guarantee: they may not find counterexamples when the program is unsafe.

We propose a novel IC3-inspired algorithm Racer for solving CHCs modulo ADT and RDF (i.e., automatically synthesizing inductive invariants, as opposed to only verifying them as is done in deductive verification). Racer ensures progress despite the undecidability of the underlying theory, and is guaranteed to terminate with a counterexample for unsafe programs. It works with a general class of RDFs over ADTs called catamorphisms. The key idea is to represent catamorphisms as both CHCs, via
relationification
, and RDFs, using novel
abstractions
. Encoding catamorphisms as CHCs allows learning inductive properties of catamorphisms, as well as preserving unsatisfiabilty of the original CHCs despite the use of RDF abstractions, whereas encoding catamorphisms as RDFs allows unfolding the recursive definition, and relying on it in solutions. Abstractions ensure that the underlying theory remains decidable. We implement our approach in Z3 and show that it works well in practice.
Effect of Pressure on Electronic and Optical Properties of SrAl2O4
Authors: Liang Hua
Published: January 2022

The effect of pressure on the electronic and optical properties of SrAl2O4 up to 25 GPa was studied by means of the pseudo-potential plane waves method within the generalized gradient approximation for exchange and correlation. The calculated lattice parameters are consistent with available experimental and theoretical data. By analyzing the electronic and optical properties, the pressure dependences of the electronic structures and optical constants were investigated. The band structures show an indirect band gap for this compound and the calculated band gaps expend with increasing pressure. Meanwhile, the optical properties including the dielectric spectra, absorption coefficient spectra, reflectivity, and the real part of the refractive index spectra in the low energy range have a blue shift. Given this, the optical properties of SrAl2O4 could be tuned by changing pressure to some degree, which is beneficial to the optical applications.
Structural, Optical, and Magnetic Properties of Gd Doped CdTe Quantum Dots for Magnetic Imaging Applications
Authors: V. Shanmugapriya , S. Bharathi , D. Esakkinaveen , S. Arunpandiyan , B. Selvakumar , G. Sasikala , R. Jayavel , A. Arivarasan
Published: January 2022

Induced room-temperature ferromagnetic behavior (RT-MF) of Gd doped CdTe (GDC) quantum dots (QDs) is reported. Pure CdTe QDs were synthesized by colloidal route using thiol stabilizers in an aqueous medium. The magnetic moments were induced by the inclusion of Gd in CdTe QDs. The effect of Gd ion substitution in CdTe lattices was characterized by X-ray diffraction which confirmed the formation of cubic zinc blende structure. The optical response of the prepared QDs was studied via UV–vis absorption spectroscopy, which indicated that Gd ion substitution alters the optical response toward a longer wavelength; this is further confirmed by corresponding emission analysis through Fluorescence emission spectroscopy. Quantum yield measurements confirmed that the GDC QDs give better quantum yield than pure CdTe QDs through the substitution of Gd ions. The formation of CdTe QDs with Gd ion substitution was confirmed by binding energy analysis through X-ray photoelectron spectroscopy. RT-MF of GDC QDs was revealed by vibrating-sample magnetometer measurement. Hence, the prepared GDC QDs were determined to be a vital DMS material for room-temperature spintronics applications.
Relationship Model between Human Resource Management Activities and Performance Based on LMBP Algorithm
Authors: Qiang Liu , Zhongwei Zhao
Published: January 2022

The research on the relationship between human resource management activities and performance is an important topic of enterprise human resource management research. There are some errors between the relationship between human resource management activities and performance and the real situation, so it is impossible to accurately predict the performance fluctuation. Therefore, the relationship model between human resource management activities and performance based on the LMBP algorithm is constructed. Using the Levenberg–Marquardt (LM) algorithm and BP (back-propagation) neural network algorithm to establish a new LMBP algorithm, control the convergence of the new algorithm, optimize the accuracy of the algorithm, and then apply the LMBP algorithm to predict the risk of performance fluctuation under human resource management activities of enterprises, the indicators of human resource management activities of enterprises are determined, to complete the mining of enterprise performance data, the grey correlation analysis is combined, and the relationship model between human resource management activities and performance is built. The experimental samples are selected from CSMAR database, and the simulation experiment is designed. Using different algorithms to forecast the fluctuation of enterprise performance, the experimental results show that the LMBP algorithm can more accurately reflect the relationship between enterprise HRM and performance.
Long Noncoding RNA LIFR‐AS1: A New Player in Human Cancers
Authors: Bai Zhiqun , Wang Xuemei , Zhang Zhen
Published: January 2022

Emerging evidence has indicated that aberrantly expressed long noncoding RNAs (lncRNAs) play a vital role in various biological processes associated with tumorigenesis. Leukemia inhibitory factor receptor antisense RNA1 (LIFR‐AS1) is a recently identified lncRNA transcribed in an antisense manner from the LIFR gene located on human chromosome 5p13.1. LIFR‐AS1 regulates tumor proliferation, migration, invasion, apoptosis, and drug resistance through different mechanisms. Its expression level is related to the clinicopathological characteristics of tumors and plays a key role in tumor occurrence and development. In this review, we summarize the role of LIFR‐AS1 in the development and progression of different cancers and highlight the potential for LIFR‐AS1 to serve as a biomarker and therapeutic target for a variety of human cancers.