bluuebunny/crossref_metadata_2025 huggingface dataset:
Transfinite step-indexing for termination
Authors: Spies Simon , Krishnaswami Neel , Dreyer Derek
Published: January 2021

Step-indexed logical relations are an extremely useful technique for building operational-semantics-based models and program logics for realistic, richly-typed programming languages. They have proven to be indispensable for modeling features like
higher-order state
, which many languages support but which were difficult to accommodate using traditional denotational models. However, the conventional wisdom is that, because they only support reasoning about finite traces of computation, (unary) step-indexed models are only good for proving
safety
properties like “well-typed programs don’t go wrong”. There has consequently been very little work on using step-indexing to establish
liveness
properties, in particular termination.

In this paper, we show that step-indexing can in fact be used to prove termination of well-typed programs—even in the presence of dynamically-allocated, shared, mutable, higher-order state—so long as one’s type system enforces disciplined use of such state. Specifically, we consider a language with asynchronous channels, inspired by promises in JavaScript, in which higher-order state is used to implement communication, and linearity is used to ensure termination. The key to our approach is to generalize from natural number step-indexing to
transfinite step-indexing
, which enables us to compute termination bounds for program expressions in a compositional way. Although transfinite step-indexing has been proposed previously, we are the first to apply this technique to reasoning about termination in the presence of higher-order state.
egg: Fast and extensible equality saturation
Authors: Willsey Max , Nandi Chandrakana , Wang Yisu Remy , Flatt Oliver , Tatlock Zachary , Panchekha Pavel
Published: January 2021

An e-graph efficiently represents a congruence relation over many expressions. Although they were originally developed in the late 1970s for use in automated theorem provers, a more recent technique known as equality saturation repurposes e-graphs to implement state-of-the-art, rewrite-driven compiler optimizations and program synthesizers. However, e-graphs remain unspecialized for this newer use case. Equality saturation workloads exhibit distinct characteristics and often require ad-hoc e-graph extensions to incorporate transformations beyond purely syntactic rewrites.

This work contributes two techniques that make e-graphs fast and extensible, specializing them to equality saturation. A new amortized invariant restoration technique called rebuilding takes advantage of equality saturation's distinct workload, providing asymptotic speedups over current techniques in practice. A general mechanism called e-class analyses integrates domain-specific analyses into the e-graph, reducing the need for ad hoc manipulation.

We implemented these techniques in a new open-source library called egg. Our case studies on three previously published applications of equality saturation highlight how egg's performance and flexibility enable state-of-the-art results across diverse domains.
Automatic differentiation in PCF
Authors: Mazza Damiano , Pagani Michele
Published: January 2021

We study the correctness of automatic differentiation (AD) in the context of a higher-order, Turing-complete language (PCF with real numbers), both in forward and reverse mode. Our main result is that, under mild hypotheses on the primitive functions included in the language, AD is almost everywhere correct, that is, it computes the derivative or gradient of the program under consideration
except
for a set of Lebesgue measure zero. Stated otherwise, there are inputs on which AD is incorrect, but the probability of randomly choosing one such input is zero. Our result is in fact more precise, in that the set of failure points admits a more explicit description: for example, in case the primitive functions are just constants, addition and multiplication, the set of points where AD fails is contained in a countable union of zero sets of polynomials.
Intersection types and (positive) almost-sure termination
Authors: Dal Lago Ugo , Faggian Claudia , Rocca Simona Ronchi Della
Published: January 2021

Randomized higher-order computation can be seen as being captured by a λ-calculus endowed with a single algebraic operation, namely a construct for binary probabilistic choice. What matters about such computations is the
probability
of obtaining any given result, rather than the
possibility
or the
necessity
of obtaining it, like in (non)deterministic computation. Termination, arguably the simplest kind of reachability problem, can be spelled out in at least two ways, depending on whether it talks about the probability of convergence or about the expected evaluation time, the second one providing a stronger guarantee. In this paper, we show that intersection types are capable of precisely characterizing
both
notions of termination inside
a single
system of types: the probability of convergence of any λ-term can be underapproximated by its
type
, while the underlying derivation’s
weight
gives a lower bound to the term’s expected number of steps to normal form. Noticeably, both approximations are tight—not only soundness but also completeness holds. The crucial ingredient is non-idempotency, without which it would be impossible to reason on the expected number of reduction steps which are necessary to completely evaluate any term. Besides, the kind of approximation we obtain is proved to be
optimal
recursion theoretically: no recursively enumerable formal system can do better than that.
A separation logic for effect handlers
Authors: de Vilhena Paulo Emílio , Pottier François
Published: January 2021

User-defined effects and effect handlers are advertised and advocated as a relatively easy-to-understand and modular approach to delimited control. They offer the ability of suspending and resuming a computation and allow information to be transmitted both ways between the computation, which requests a certain service, and the handler, which provides this service. Yet, a key question remains, to this day, largely unanswered: how does one modularly specify and verify programs in the presence of both user-defined effect handlers and primitive effects, such as heap-allocated mutable state? We answer this question by presenting a Separation Logic with built-in support for effect handlers, both shallow and deep. The specification of a program fragment includes a protocol that describes the effects that the program may perform as well as the replies that it can expect to receive. The logic allows local reasoning via a frame rule and a bind rule. It is based on Iris and inherits all of its advanced features, including support for higher-order functions, user-defined ghost state, and invariants. We illustrate its power via several case studies, including (1) a generic formulation of control inversion, which turns a producer that ``pushes'' elements towards a consumer into a producer from which one can ``pull'' elements on demand, and (2) a simple system for cooperative concurrency, where several threads execute concurrently, can spawn new threads, and communicate via promises.
The fine-grained and parallel complexity of andersen’s pointer analysis
Authors: Mathiasen Anders Alnor , Pavlogiannis Andreas
Published: January 2021

Pointer analysis is one of the fundamental problems in static program analysis. Given a set of pointers, the task is to produce a useful over-approximation of the memory locations that each pointer may point-to at runtime. The most common formulation is Andersen’s Pointer Analysis (APA), defined as an inclusion-based set of
m
pointer constraints over a set of
n
pointers. Scalability is extremely important, as points-to information is a prerequisite to many other components in the static-analysis pipeline. Existing algorithms solve APA in
O
(
n
2
·
m
) time, while it has been conjectured that the problem has no truly sub-cubic algorithm, with a proof so far having remained elusive. It is also well-known that APA can be solved in
O
(
n
2
) time under certain sparsity conditions that hold naturally in some settings. Besides these simple bounds, the complexity of the problem has remained poorly understood.

In this work we draw a rich fine-grained and parallel complexity landscape of APA, and present upper and lower bounds. First, we establish an
O
(
n
3
) upper-bound for general APA, improving over
O
(
n
2
·
m
) as
n
=
O
(
m
). Second, we show that even on-demand APA (“may a specific pointer
a
point to a specific location
b
?”) has an Ω(
n
3
) (combinatorial) lower bound under standard complexity-theoretic hypotheses. This formally establishes the long-conjectured “cubic bottleneck” of APA, and shows that our
O
(
n
3
)-time algorithm is optimal. Third, we show that under mild restrictions, APA is solvable in Õ(
n
ω
) time, where ω<2.373 is the matrix-multiplication exponent. It is believed that ω=2+
o
(1), in which case this bound becomes quadratic. Fourth, we show that even under such restrictions, even the on-demand problem has an Ω(
n
2
) lower bound under standard complexity-theoretic hypotheses, and hence our algorithm is optimal when ω=2+
o
(1). Fifth, we study the parallelizability of APA and establish lower and upper bounds: (i) in general, the problem is P-complete and hence unlikely parallelizable, whereas (ii) under mild restrictions, the problem is parallelizable. Our theoretical treatment formalizes several insights that can lead to practical improvements in the future.
Distributed causal memory: modular specification and verification in higher-order distributed separation logic
Authors: Gondelman Léon , Gregersen Simon Oddershede , Nieto Abel , Timany Amin , Birkedal Lars
Published: January 2021

We present the first specification and verification of an implementation of a causally-consistent distributed database that supports modular verification of full functional correctness properties of clients and servers. We specify and reason about the causally-consistent distributed database in Aneris, a higher-order distributed separation logic for an ML-like programming language with network primitives for programming distributed systems. We demonstrate that our specifications are useful, by proving the correctness of small, but tricky, synthetic examples involving causal dependency and by verifying a session manager library implemented on top of the distributed database. We use Aneris's facilities for modular specification and verification to obtain a highly modular development, where each component is verified in isolation, relying only on the specifications (not the implementations) of other components. We have used the Coq formalization of the Aneris logic to formalize all the results presented in the paper in the Coq proof assistant.
The (In)Efficiency of interaction
Authors: Accattoli Beniamino , Dal Lago Ugo , Vanoni Gabriele
Published: January 2021

Evaluating higher-order functional programs through abstract machines inspired by the geometry of the interaction is known to induce
space
efficiencies, the price being
time
performances often poorer than those obtainable with traditional, environment-based, abstract machines. Although families of lambda-terms for which the former is exponentially less efficient than the latter do exist, it is currently unknown how
general
this phenomenon is, and how far the inefficiencies can go, in the worst case. We answer these questions formulating four different well-known abstract machines inside a common definitional framework, this way being able to give sharp results about the relative time efficiencies. We also prove that non-idempotent intersection type theories are able to precisely reflect the time performances of the interactive abstract machine, this way showing that its time-inefficiency ultimately descends from the presence of higher-order types.
Corpse reviver: sound and efficient gradual typing via contract verification
Authors: Moy Cameron , Nguyễn Phúc C. , Tobin-Hochstadt Sam , Van Horn David
Published: January 2021

Gradually typed programming languages permit the incremental addition of static types to untyped programs. To remain sound, languages insert run-time checks at the boundaries between typed and untyped code. Unfortunately, performance studies have shown that the overhead of these checks can be disastrously high, calling into question the viability of sound gradual typing. In this paper, we show that by building on existing work on soft contract verification, we can reduce or eliminate this overhead.

Our key insight is that while untyped code cannot be trusted by a gradual type system, there is no need to consider only the worst case when optimizing a gradually typed program. Instead, we statically analyze the untyped portions of a gradually typed program to prove that almost all of the dynamic checks implied by gradual type boundaries cannot fail, and can be eliminated at compile time. Our analysis is modular, and can be applied to any portion of a program.

We evaluate this approach on a dozen existing gradually typed programs previously shown to have prohibitive performance overhead—with a median overhead of 2.5× and up to 80.6× in the worst case—and eliminate all overhead in most cases, suffering only 1.5× overhead in the worst case.
Deciding reachability under persistent x86-TSO
Authors: Abdulla Parosh Aziz , Atig Mohamed Faouzi , Bouajjani Ahmed , Kumar K. Narayan , Saivasan Prakash
Published: January 2021

We address the problem of verifying the reachability problem in programs running under the formal model Px86 defined recently by Raad et al. in POPL'20 for the persistent Intel x86 architecture. We prove that this problem is decidable. To achieve that, we provide a new formal model that is equivalent to Px86 and that has the feature of being a well structured system. Deriving this new model is the result of a deep investigation of the properties of Px86 and the interplay of its components.
On the complexity of bidirected interleaved Dyck-reachability
Authors: Li Yuanbo , Zhang Qirun , Reps Thomas
Published: January 2021

Many program analyses need to reason about pairs of matching actions, such as call/return, lock/unlock, or set-field/get-field. The family of Dyck languages {
D

k

}, where
D

k

has
k
kinds of parenthesis pairs, can be used to model matching actions as balanced parentheses. Consequently, many program-analysis problems can be formulated as Dyck-reachability problems on edge-labeled digraphs.
Interleaved Dyck-reachability
(InterDyck-reachability), denoted by
D

k

⊙
D

k

-reachability, is a natural extension of Dyck-reachability that allows one to formulate program-analysis problems that involve
multiple
kinds of matching-action pairs. Unfortunately, the general InterDyck-reachability problem is undecidable.

In this paper, we study variants of InterDyck-reachability on
bidirected graphs
, where for each edge ⟨
p
,
q
⟩ labeled by an open parenthesis ”(

a

”, there is an edge ⟨
q
,
p
⟩ labeled by the corresponding close parenthesis ”)

a

”, and
vice versa
. Language-reachability on a bidirected graph has proven to be useful both (1) in its own right, as a way to formalize many program-analysis problems, such as pointer analysis, and (2) as a
relaxation
method that uses a fast algorithm to over-approximate language-reachability on a directed graph. However, unlike its directed counterpart, the complexity of bidirected InterDyck-reachability still remains open.

We establish the first decidable variant (i.e.,
D
1
⊙
D
1
-reachability) of bidirected InterDyck-reachability. In
D
1
⊙
D
1
-reachability, each of the two Dyck languages is restricted to have only a single kind of parenthesis pair. In particular, we show that the bidirected
D
1
⊙
D
1
problem is in PTIME. We also show that when one extends each Dyck language to involve
k
different kinds of parentheses (i.e.,
D

k

⊙
D

k

-reachability with
k
≥ 2), the problem is NP-hard (and therefore much harder).

We have implemented the polynomial-time algorithm for bidirected
D
1
⊙
D
1
-reachability.
D

k

⊙
D

k

-reachability provides a new over-approximation method for bidirected
D

k

⊙
D

k

-reachability in the sense that
D

k

⊙
D

k

-reachability can first be relaxed to bidirected
D
1
⊙
D
1
-reachability, and then the resulting bidirected
D
1
⊙
D
1
-reachability problem is solved precisely. We compare this
D
1
⊙
D
1
-reachability-based approach against another known over-approximating
D

k

⊙
D

k

-reachability algorithm. Surprisingly, we found that the over-approximation approach based on bidirected
D
1
⊙
D
1
-reachability computes
more precise
solutions, even though the
D
1
⊙
D
1
formalism is inherently less expressive than the
D

k

⊙
D

k

formalism.
Mitigating Inter-Job Interference via Process-Level Quality-of-Service
Authors: Savoie Lee , Lowenthal David K. , Supinski Bronis R. De , Mohror Kathryn , Jain Nikhil
Published: January 2021

Jobs on most high-performance computing (HPC) systems share the network with other concurrently executing jobs. Network sharing leads to contention that can severely degrade performance. This article investigates the use of Quality of Service (QoS) mechanisms to reduce the negative impacts of network contention. QoS allows users to manage resource sharing between network flows and to provide bandwidth guarantees to specific flows. Our results show that careful use of QoS reduces the impact of network contention for specific jobs, resulting in up to a 40% performance improvement. In some cases, it completely eliminates the impact of contention. It achieves these improvements with limited negative impact to other jobs; any job that experiences performance loss typically degrades less than 5%, and often much less. Our approach can help ensure that HPC machines maintain high levels of throughput as per-node compute power continues to increase faster than network bandwidth.
Optimizing Electrolyte Additive Loadings in NMC532/Graphite Cells: Vinylene Carbonate and Ethylene Sulfate
Authors: Taskovic T. , Thompson L. M. , Eldesoky A. , Lumsden M. D. , Dahn J. R.
Published: January 2021

A matrix of LiNi0.5Mn0.3Co0.2O2/graphite cells filled with 1.33 molal LiPF6 in EC:EMC:DMC (ethylene carbonate: ethyl methyl carbonate: dimethyl carbonate) (25:5:70 by volume) electrolyte and different weight percentages of vinylene carbonate (VC) and ethylene sulfate (DTD) electrolyte additives underwent prolonged charge-discharge cycling at 20 °C and 40 °C. The volume of gas produced during formation and cycle testing was measured. The impedance spectra of the cells before and after cycling was measured. After testing, the electrolyte was extracted for study by nuclear magnetic resonance spectroscopy (NMR) and gas chromatography/mass spectroscopy (GC-MS) to determine what changes in electrolyte composition had occurred. Some cells had their negative electrodes studied by scanning micro-X-ray fluorescence to quantify the amount of transition metals that transferred from the positive electrode to the negative electrode during the testing. Cells containing 1% VC or 2% VC with an additional 1% DTD by weight had the best capacity retention and lowest impedance growth. NMR and GC-MS suggest that these additive combinations promote increased electrolyte salt consumption which may represent a source of lithium to replenish the lithium inventory. Only a small amount of transition metals (0.03% or less) originating from the positive electrode active material was found on the negative electrode after testing. Most cells had over 1500 cycles at both 20 °C and 40 °C conditions.
CAPTCHA Recognition Method Based on CNN with Focal Loss
Authors: Wang Zhong , Shi Peibei
Published: January 2021

In order to distinguish between computers and humans, CAPTCHA is widely used in links such as website login and registration. The traditional CAPTCHA recognition method has poor recognition ability and robustness to different types of verification codes. For this reason, the paper proposes a CAPTCHA recognition method based on convolutional neural network with focal loss function. This method improves the traditional VGG network structure and introduces the focal loss function to generate a new CAPTCHA recognition model. First, we perform preprocessing such as grayscale, binarization, denoising, segmentation, and annotation and then use the Keras library to build a simple neural network model. In addition, we build a terminal end‐to‐end neural network model for recognition for complex CAPTCHA with high adhesion and more interference pixel. By testing the CNKI CAPTCHA, Zhengfang CAPTCHA, and randomly generated CAPTCHA, the experimental results show that the proposed method has a better recognition effect and robustness for three different datasets, and it has certain advantages compared with traditional deep learning methods. The recognition rate is 99%, 98.5%, and 97.84%, respectively.
Evaluation of the Adsorption Efficiency of Glycine-, Iminodiacetic Acid -, and Amino Propyl-Functionalized Silica Nanoparticles for the Removal of Potentially Toxic Elements from Contaminated Water Solution
Authors: Alswieleh Abdullah M. , Albahar Hajar Y. , Alfawaz Amal M. , Alsilme Abdulilah S. , Beagan Abeer M. , Alsalme Ali M. , Almeataq Mohammed S. , Alshahrani Ahmed , Alotaibi Khalid M.
Published: January 2021

In present work, mesoporous silica nanoparticles (MSNs) were prepared with a surface area of 1048 m2g-1 and a large pore size of ca. 6 nm, using Stöber process in the presence of expanding reagent (

n

-hexane). The surface of MSNs was modified with three different functional groups (amine, iminodiacetic acid, and glycine) and characterized by a variety of physicochemical techniques. The adsorption studies were carried out at different pH values in two extraction systems. In batch method, the maximum adsorption efficiency of heavy metals was measured to be 95% for all fabricated MSNs at pH 9. At pH 3, the adsorption efficiency of Pb and Cu was observed to be affected by the carboxylic moiety involved in the functional group. As the number of carboxylic moieties increase, the removal efficiency of Pb and Cu ions increased by two folds. The results demonstrated the selectivity of IDA-MSNs for the removal of Pb and Cu ions, even though the multielements are present in an aqueous solution. On the other hand, the incorporation of MSNs into the polymeric membrane showed high water permeability (

9.96
±
3
 
L
/

m

2

.
h
.
bar

), and 98% rejection was achieved at pH 7 for Cu+2 and Pb+2 ions.
Autotransplantation of Two Immature Third Molars with the Use of L-PRF
Authors: Rey Lescure Manon , Valente Nicola Alberto , Chatelain Sibylle , Cinquini Chiara , Barone Antonio
Published: January 2021

Tooth autotransplantation is a procedure which provides the extraction of an erupted or impacted tooth and its repositioning to another site in the oral cavity. This Case Report describes a successful case of two autotransplantations of open-apex mandibular third molars in place of the hopeless first mandibular molars with the use of L-PRF in a growing patient. A 15-year-old male patient was referred to the Dental Clinic for the extractions of the two hopeless mandibular first molars. Autotransplantation was considered the best treatment option for both sites 36 and 46, because the presence of two impacted mandibular third molars (38 and 48) with an incomplete root formation. Teeth 36 and 46 were extracted and replaced with teeth 38 and 48. The patient had an uneventful healing. At follow-up visits, the two autotransplanted teeth showed physiologic mobility, absence of inflammation and discomfort, and absence of infection; probing depth values were within normal range, and the vitality tests were positive. After 2 years, the teeth in position 36 and 46 showed absence of infection and mobility, and positive pulp vitality tests and the radiographic examinations exhibited closure of the root apices as well as absence of any periapical radiolucency or root resorption. Tooth autotransplantation is a good treatment option in case of tooth loss offering an alternative to traditional or implant-supported prosthesis especially for growing patients.
A Dynamic Variance‐Based Triggering Scheme for Distributed Cooperative State Estimation over Wireless Sensor Networks
Authors: Zhu Hongbo , Ding Jiabao
Published: January 2021

Wireless sensor networks (WSNs) have been spawning many new applications where cooperative state estimation is essential. In this paper, the problem of performing cooperative state estimation for a discrete linear stochastic dynamical system over wireless sensor networks with a limitation on the sampling and communication rate is considered, where distributed sensors cooperatively sense a linear dynamical process and transmit observations each other via a common wireless channel. Firstly, a novel dynamic variance‐based triggering scheme (DVTS) is designed to schedule the sampling of each sensor and the transmission of its local measurement. In contrast to the existing static variance‐based triggering scheme (SVTS), the newly proposed DVTS can lead to the larger average intertrigger time interval and thus fewer total triggering number with almost approximate estimation accuracy. Second, a new Riccati equation of the prediction variance iteration for each estimator is obtained, which switches dynamically among the modes related to the variance of the previous step and the recently received measurements from other sensors. Furthermore, the stability issue is also mainly investigated. Finally, simulation results show the effectiveness and advantage of the proposed strategy.
Two Effective Strategies to Support Cross-Organization Emergency Resource Allocation Optimization
Authors: Gao Ying , Liu Cong , Zeng Qingtian , Duan Hua
Published: January 2021

Cross-organization emergency resource allocation optimization problem is essential to guarantee a successful emergency disposal, and it has become a research focus of modern emergency management. Generally speaking, there are two possible types of resource allocation scenarios: (1) if the emergency resources are overallocated, on the one hand, parallel execution of independent emergency activities can be supported and the emergency disposal time is reduced; on the other hand, too many idle resources may cause low resource utilization rate, high scheduling overhead, and high cost; and (2) if emergency resources are underallocated, this may lead to resource conflicts and the need for some emergency activities to wait for others to complete, and finally the emergency disposal time may increase. Therefore, reasonable emergency resource allocation strategies are highly desired. To the best of our knowledge, there is no formal approach to support the cross-organization emergency resource allocation issue. To handle this problem, we propose a two-layered framework to facilitate the allocation of limited emergency resources to meet its time constraints with high efficiency. More specifically, a kind of Petri net extended with time, resource, and message information, denoted as CE-net, is presented to model cross-organization emergency response processes. Based on the obtained CE-net, the minimum resource requirements are obtained with corresponding algorithms. Then, Minimum Execution Time (MET) strategy and Minimum Resource Consumption (MRC) strategy with their corresponding estimated execution intervals are introduced to facilitate the stakeholder to determine which strategy is suitable according to the timing requirements. A cross-organization fire emergency case is applied to validate the proposed approaches throughout the whole paper.
Surface Plasmon Resonance Sensor to Detect n‐Hexane in Palm Kernel Oil Using Polypyrrole Nanoparticles Reduced Graphene Oxide Layer
Authors: Sadrolhosseini Amir Reza , Habibiasr Mina , Soleimani Hassan , Hamidon Mohd Nizar , Fen Yap Wing , Lim H. N.
Published: January 2021

Palm kernel oil was extracted using n‐hexane. Rotary evaporator and oven were used to remove n‐hexane from the oil. Measurement of n‐hexane in low concentration is significant and interest subject. In this study, the concentration of n‐hexane was measured using the surface plasmon resonance technique. In order to improve the sensitivity of surface plasmon resonance sensor, the polypyrrole nanoparticles decorated reduced graphene oxide (sensing layer) was prepared using the electrodeposition technique on the surface of gold film. Different concentration of n‐hexane in isooctane and the palm kernel oil before and after purification was tested using sensing layer. The sensor limit was about 1 ppm. The results were matched with the gas chromatography results. The thickness and roughness of sensing layer were increased after the interaction with n‐hexane which was obtained from atomic force microscopy.
Association of Apolipoprotein E Polymorphisms and Risks of Ischemic Stroke in Chinese Patients with Type 2 Diabetes Mellitus
Authors: Wang Na , Liu Qian , Liu Hui , Cong Xiao , Yang Hui , Yu Yang , Cao Yongtong , Ma Liang
Published: January 2021

Background. The apolipoprotein E (APOE) gene polymorphisms have been intensively studied in patients with type 2 diabetes mellitus (T2DM) and ischemic stroke (IS) in recent years. However, it is unclear whether APOE gene polymorphisms are correlated with increased risk for developing IS in T2DM patients. Thus, this study was designed to examine the association between APOE gene polymorphisms and risks of IS in Chinese patients with T2DM. Methods. This case-control study enrolled 243 subjects with T2DM as controls, and 210 subjects with T2DM complicated with IS as case patients. The genotypes were determined using real-time PCR while HbA1c and lipid levels were detected using commercially available kits. Results. The systolic blood pressure (SBP), diastolic blood pressure (DBP), and the proportion of patients with a history of hypertension were higher in the case patients than that in the controls. We confirmed that the ε2/ε3 genotype, as well as SBP and history of hypertension, was the independent risk factor for developing IS in T2DM patients. Conclusions. We conclude that the ε2/ε3 genotype might contribute to the increased risk for developing IS in Chinese patients with T2DM.
Lighting a Fire: Can We Harness Pyroptosis to Ignite Antitumor Immunity?
Authors: Zhang Zhibin , Zhang Ying , Lieberman Judy
Published: January 2021

The impressive success of current cancer immunotherapy in some patients but lack of effectiveness in most patients suggests that additional strategies to promote antitumor immunity are needed. How cancer cells die, whether spontaneously or in response to therapeutic intervention, has a profound effect on the type of immune response mobilized. Here, we review research that highlights a previously unappreciated role of gasdermin-mediated inflammatory death (pyroptosis) to promote antitumor immunity and identifies gasdermin E as a tumor suppressor. Immune elimination of tumor cells by natural killer cells and cytotoxic T lymphocytes, which is the final key event in antitumor immunity, was previously thought to be noninflammatory. The research shows that gasdermin expression in tumor cells converts immune cell–mediated killing to inflammatory pyroptosis when cell death–inducing granzymes directly cleave and activate gasdermins. Granzyme B cleaves gasdermin E, and granzyme A cleaves gasdermin B. The data suggest the potential to harness pyroptosis in the tumor to ignite an effective immune response to immunologically cold tumors. Gasdermin expression also augments toxicity of cancer therapy—gasdermin E expression by B-cell leukemias and lymphomas is a root cause of chimeric antigen receptor (CAR) T–cell cytokine storm, and its expression in normal tissues promotes the toxicity of chemotherapeutic drugs. Even though our knowledge about the role of pyroptosis in cancer is growing, there is still a lot to learn—what activates it, how it is regulated, when it is beneficial, and how it can be harnessed therapeutically to improve cancer immunotherapy or reduce therapy-related toxicity.
Choroidal Metastasis Secondary to Testicular Mature Teratoma: A Case Report
Authors: Bata Bashar M. , Salvi Sachin M.
Published: January 2021

We report a case of a choroidal metastasis secondary to testicular mature teratoma, a subtype of non-seminoma germ cell tumours, in a young adult male. The choroidal metastasis was treated successfully with bleomycin, etoposide, and cisplatin chemotherapy without the need for adjuvant radiotherapy. This represents a rare case of mature teratoma metastasizing to the choroid and one of very few reported testicular germ cell tumours to achieve normal or near normal visual acuity with chemotherapy alone despite severe macular disease at presentation.
The Clinical Characteristics and Outcomes of COVID-19 Infections in Patients with Diabetes at a Tertiary Care Center in the UAE
Authors: Hafidh Khadija , Abbas Saira , Khan Arhsee , Kazmi Touseef , Nazir Zufana , Aldaham Tahani
Published: January 2021

Introduction: Uncontrolled glycemia is a well-recognized predictor of severity and deaths in previous respiratory viral outbreaks. We aimed to describe the characteristics and clinical course of patients with diabetes admitted with COVID-19 infection at a tertiary care center in the Emirate of Dubai, UAE, and assess the impact of hyperglycemia on the clinical outcomes. Methods: This study is a single-center, observational, retrospective chart review of 250 cases during the months of March to May 2020. Results: Among the 250 cases studied, 235 (94%) were male. The mean age of the study group was 49.6 ± 10.4 years, with an age range of 21–78 years. Diabetes was previously known in 166 (66.4%) of the patients. The mortality (p = 0.03) and requirement for mechanical ventilation (p = 0.02) were higher for the cases with newly diagnosed diabetes when compared to those with pre-existing diabetes. Conclusion: Uncontrolled hyperglycemia adversely affects patients with COVID-19 infection. Newly diagnosed and previously undiagnosed hyperglycemia poses an added risk for complications. In the context of the COVID-19 pandemic, optimizing glycemia in hospitalized patients is of paramount importance and screening to detect undiagnosed cases of diabetes may be particularly relevant.
Acessível ou não? Eis a questão!
Authors: Rodrigues Luciana , Cheibub Bernardo Lazary
Published: January 2021

Paraty é um município de patrimônios naturais, históricos e culturais, que lhe renderam o título de Patrimônio Mundial como Sítio Misto, mas que não possibilita que todas as pessoas possam visitá-lo de forma autônoma e segura. A investigação que originou este artigo teve como objetivos reconhecer as barreiras que prejudicam a mobilidade de pessoas com deficiência (PCDs) no Centro Histórico (CH) de Paraty e arredores, bem como analisar se há um paradoxo entre tombamento de patrimônio e acessibilidade. A partir de uma pesquisa qualitativa exploratória de base etnográfica, foram realizadas observações diretas em campo, o acompanhamento da experiência turística in loco de uma pessoa com deficiência física e entrevistas, com roteiro semiestruturado, com agentes sociais do Instituto do Patrimônio Histórico e Artístico Nacional (IPHAN) e da Gestão Pública Municipal. Além disso, foram examinados documentos e legislações acerca da acessibilidade daquela cidade.  Conclui-se que, devido às diversas barreiras estruturais e a ausência de ações do poder público, Paraty, uma cidade extremamente turística, não proporciona acessibilidade plena às PCDs. Pretende-se com este trabalho contribuir para a discussão sobre a inclusão das PCDs na sociedade, mostrando a importância da acessibilidade no desfrute de experiências turísticas nos destinos desejados.
Identifying Isolated Systolic Hypertension From Upper-Arm Cuff Blood Pressure Compared With Invasive Measurements
Authors: Picone Dean S. , Schultz Martin G. , Armstrong Matthew K. , Black J. Andrew , Bos Willem Jan W. , Chen Chen-Huan , Cheng Hao-Min , Cremer Antoine , Dwyer Nathan , Hughes Alun D. , Kim Hack-Lyoung , Lacy Peter S. , Laugesen Esben , Liang Fuyou , Ohte Nobuyuki , Okada Sho , Omboni Stefano , Ott Christian , Pereira Telmo , Pucci Giacomo , Schmieder Roland E. , Sinha Manish D. , Stouffer George A. , Takazawa Kenji , Roberts-Thomson Philip , Wang Ji-Guang , Weber Thomas , Westerhof Berend E. , Williams Bryan , Sharman James E. ,   for the Invasive Blood Pressure Consortium
Published: January 2021

Isolated systolic hypertension (ISH) is the most common form of hypertension and is highly prevalent in older people. We recently showed differences between upper-arm cuff and invasive blood pressure (BP) become greater with increasing age, which could influence correct identification of ISH. This study sought to determine the difference between identification of ISH by cuff BP compared with invasive BP. Cuff BP and invasive aortic BP were measured in 1695 subjects (median 64 years, interquartile range [55–72], 68% male) from the INSPECT (Invasive Blood Pressure Consortium) database. Data were recorded during coronary angiography among 29 studies, using 21 different cuff BP devices. ISH was defined as ≥130/<80 mm Hg using cuff BP compared with invasive aortic BP as the reference. The prevalence of ISH was 24% (n=407) according to cuff BP but 38% (n=642) according to invasive aortic BP. There was fair agreement (Cohen κ, 0.36) and 72% concordance between cuff and invasive aortic BP for identifying ISH. Among the 28% of subjects (n=471) with misclassification of ISH status by cuff BP, 20% (n=96) of the difference was due to lower cuff systolic BP compared with invasive aortic systolic BP (mean, −16.4 mm Hg [95% CI, −18.7 to −14.1]), whereas 49% (n=231) was from higher cuff diastolic BP compared with invasive aortic diastolic BP (+14.2 mm Hg [95% CI, 11.5−16.9]). In conclusion, compared with invasive BP, cuff BP fails to identify ISH in a sizeable portion of older people and demonstrates the need to improve cuff BP measurements.
Impact of a Low-Cost Postsecondary Enrollment Intervention: Evidence from
Louisiana
Authors: Joshi Swarup , Barnes Stephen
Published: January 2021

It is well understood that postsecondary education increases lifetime earnings, yet the complexity of the college application process creates a barrier to postsecondary enrollment. This paper investigates a whole-school external application assistance program run by a nonprofit student support services organization, Career Compass of Louisiana. We use panel data of Louisiana high schools in a difference-in-differences framework and find that exposure to Career Compass increases postsecondary enrollment by 3.9 percentage points. Moreover, the effect of exposure is larger in school districts with a majority of black students as well as districts with a majority of low-income students. By providing services to all schools within a district, the program is able to achieve low costs relative to similar programs and effects that are in line with many more expensive programs, suggesting that scaling this model to new areas could provide a cost-effective approach to increasing postsecondary enrollment among high school graduates.
Oil transportation: Eni’s fleet, Italian ports and pipelines, 1950-1980
Authors: Suffia Ilaria , Locatelli Andrea Maria , Romano Maurizio
Published: January 2021

To make their business profitable, oil multinationals have to include in their strategies the transport of crude oil from production sites to markets. This article focuses on Ente Nazionale Idrocarburi (Eni), the Italian state-owned oil company – a significant firm in the oil industry in the second half of the twentieth century – to show how oil businesses have overcome trading limitations by establishing transportation systems comprising ships, ports and pipelines. Initially, the article focuses on the relationship between oil market growth and the development of oil transport from 1945 until the early 1970s. Secondly, it analyses the growth of Eni’s fleet and the increase in ship size, emphasising limitations and constraints in an international perspective. Finally, the development of ports and pipelines – vital links in the oil supply chain – is assessed.
The development of maritime radar. Part 2: Since 1939
Authors: Ilcev Dimov Stojce
Published: January 2021

This research note outlines advances in the development of shipborne radar in Britain, Germany, the US and the Soviet Union. It focuses on the inventions and innovations in electronic and radars techniques for military and commercial applications on the eve of the Second World War, during the war and in the post-war period.
Allied blockade in the Mid-East Atlantic during the First World War: cruisers against commerce-raiders
Authors: Ponce Javier
Published: January 2021

This article examines the Allied blockade around the Canary Islands as a response to the German cruiser war, since the crossroads of trade routes from the South Atlantic that took place in the Canary Islands allowed the German commerce-raiders to ensure, on the one hand, the encounter with numerous enemy merchant ships, objectives of this economic war and, on the other hand, the aid of the numerous German merchant ships that were in their ports, especially as colliers. The immediate Allied action to block the ports in the Canary Islands took advantage of the undisputed hegemony of Great Britain in the archipelago: the British control of the main infrastructures and port and communication services was added by the joint diplomatic pressure of the British and French, although it was the clear superiority of the British naval forces and the vigilance of their cruisers that most contributed to limiting assistance to German commerce-raiders. Primary and secondary sources, diplomatic and military, both British and Spanish, and also French, shed light on the diplomatic and strategic dimension of a blockade in which the British Admiralty managed to end the threat of German commerce-raiders between August 1914 and March of 1915, and limit the operations of the following German auxiliary cruisers, which briefly operated in the eastern central Atlantic in the early months of 1916.
A dynamic trajectory planning method for lane-changing maneuver of connected and automated vehicles
Authors: Liu Xiao , Liang Jun , Fu Junwei
Published: January 2021

This paper describes a dynamic trajectory planning method for lane-changing maneuver of connected and automated vehicles (CAVs). The proposed dynamic lane-changing trajectory planning (DLTP) model adopts vehicle-to-vehicle (V2V) communication to generate an automated lane-changing maneuver with avoiding potential collisions and rollovers during the lane-changing process. The novelty of this method is that the DLTP model combines a detailed velocity planning strategy and considers more complete driving environment information. Besides, a lane-changing safety monitoring algorithm and a lane-changing starting-point determination algorithm are presented to guarantee the lane-changing safety, efficiency and stability of automated vehicles. Moreover, a trajectory-tracking controller based on model predictive control (MPC) is introduced to make the automated vehicle travel along the reference trajectory. The field traffic data from NGSIM are selected as the target dataset to simulate a real-world lane-changing driving environment. The simulations are performed in CarSim-Simulink platform and the experimental results show that the proposed method is effective for lane-changing maneuver.
Neurological and Neuropsychological Changes Associated with SARS-CoV-2 Infection: New Observations, New Mechanisms
Authors: Haidar Muhammad Ali , Jourdi Hussam , Haj Hassan Zeinab , Ashekyan Ohanes , Fardoun Manal , Wehbe Zena , Maaliki Dina , Wehbe Maya , Mondello Stefania , Abdelhady Samar , Shahjouei Shima , Bizri Maya , Mechref Yehia , Gold Mark S , Dbaibo Ghassan , Zaraket Hassan , Eid Ali H. , Kobeissy Firas
Published: January 2021

SARS-CoV-2 infects cells through angiotensin-converting enzyme 2 (ACE2), a ubiquitous receptor that interacts with the virus’ surface S glycoprotein. Recent reports show that the virus affects the central nervous system (CNS) with symptoms and complications that include dizziness, altered consciousness, encephalitis, and even stroke. These can immerge as indirect immune effects due to increased cytokine production or via direct viral entry into brain tissue. The latter is possible through neuronal access via the olfactory bulb, hematogenous access through immune cells or directly across the blood-brain barrier (BBB), and through the brain’s circumventricular organs characterized by their extensive and highly permeable capillaries. Last, the COVID-19 pandemic increases stress, depression, and anxiety within infected individuals, those in isolation, and high-risk populations like children, the elderly, and health workers. This review surveys the recent updates of CNS manifestations post SARS-CoV-2 infection along with possible mechanisms that lead to them.
Risk Factors for Assault and Physical Aggression Among Medically Hospitalized Adult Patients Who Had a Behavioral Emergency Call: A Descriptive Study
Authors: Derscheid Della J. , Lohse Christine , Arnetz Judith E.
Published: January 2021

BACKGROUND:

Health care settings are a primary location for workplace violence that involves clients, but risk factors for behavioral emergencies in medical settings are largely unknown.

AIM:

This study proposed to identify risk factors for assault and physical aggression among medically hospitalized patients who needed a behavior emergency response team.

METHOD:

This descriptive study, conducted at a large Midwestern academic medical center, used univariable and multivariable logistic regression to assess relationships between demographic, medical, mental health, and contextual variables with assault and physical aggression. Predictive ability was summarized using area under the receiver operating characteristic curve.

RESULTS:

Among patients who received a behavior emergency response ( N = 820), 86 (10%) were assaultive. Physical aggression was the most significant predictor of assault. Physical aggression was predicted by older age, male gender, and verbal threats to others. Conversely, internalizing mental health conditions of anxiety, depression, and suicidal ideation were significant for decreased risk of assault and/or physical aggression. Contextual factors, identified as wanting to smoke or leave the hospital, were significantly associated with decreased risk of both assault and physical aggression.

CONCLUSION:

Health care providers are encouraged to (1) consider the demonstration of physical aggression as a sign to urgently implement precautionary measures for safety, (2) avoid predicting violent situations based on particular medical or mental health conditions alone, and (3) understand that not all disruptive behavior leads to violent situations.
Directional sound field decay analysis in performance spaces
Authors: Berzborn Marco , Vorländer Michael
Published: January 2021

The analysis of the spatio-temporal features of sound fields is of great interest in the field of room acoustics, as they inevitably contribute to a listeners impression of the room. The perceived spaciousness is linked to lateral sound incidence during the early and late part of the impulse response which largely depends on the geometry of the room. In complex geometries, particularly in rooms with reverberation reservoirs or coupled spaces, the reverberation process might show distinct spatio-temporal characteristics.

In the present study, we apply the analysis of directional energy decay curves based on the decomposition of the sound field into a plane wave basis, previously proposed for reverberation room characterization, to general purpose performance spaces. A simulation study of a concert hall and two churches is presented uncovering anisotropic sound field decays in two cases and highlighting implications for the resulting temporal evolution of the sound field diffuseness.