bluuebunny/crossref_metadata_2025 huggingface dataset:
Rigid continuation paths I. Quasilinear average complexity for solving polynomial systems
Authors: Lairez Pierre
Published: October 2019

How many operations do we need on average to compute an approximate root of a random Gaussian polynomial system? Beyond Smale’s 17th problem that asked whether a polynomial bound is possible, we prove a quasi-optimal bound

(input size)

1
+
o
(
1
)

\text {(input size)}^{1+o(1)}

. This improves upon the previously known

(input size)

3
2

+
o
(
1
)

\text {(input size)}^{\frac 32 +o(1)}

bound.

The new algorithm relies on numerical continuation along rigid continuation paths. The central idea is to consider rigid motions of the equations rather than line segments in the linear space of all polynomial systems. This leads to a better average condition number and allows for bigger steps. We show that on average, we can compute one approximate root of a random Gaussian polynomial system of 

n
n

equations of degree at most 

D
D

in 

n
+
1

n+1

homogeneous variables with 

O
(

n
4

D
2

)

O(n^4 D^2)

continuation steps. This is a decisive improvement over previous bounds that prove no better than 

2

min
(
n
,
D
)

\sqrt {2}^{\min (n, D)}

continuation steps on average.
𝑉-harmonic morphisms between Riemannian manifolds
Authors: Zhao Guangwen
Published: October 2019

A

V
V

-harmonic morphism

u
:
M
→
N

u:M\to N

between Riemannian manifolds is a smooth map which pulls back germs of harmonic functions on

N
N

to germs of

V
V

-harmonic functions on

M
M

, where

V
V

is a smooth vector field on

M
M

. In this paper, we give some characterizations and examples of

V
V

-harmonic morphisms. In addition, a dilation estimate and a Liouville-type theorem of

V
V

-harmonic morphisms from noncompact complete manifolds are also established. As applications, we obtain the Liouville-type theorems for

V
V

-harmonic morphisms from complete manifolds of nonnegative Bakry-Émery Ricci curvature, especially complete steady or shrinking Ricci solitons, to manifolds of dimension at least three or compact Riemann surface of genus at least two.
A nonstable 𝐶*-algebra with an elementary essential composition series
Authors: Ghasemi Saeed , Koszmider Piotr
Published: October 2019

A

C
∗

C^*

-algebra

A

\mathcal {A}

is said to be stable if it is isomorphic to

A

⊗

K

(

ℓ
2

)

\mathcal {A} \otimes \mathcal {K}(\ell _2)

. Hjelmborg and Rørdam have shown that countable inductive limits of separable stable

C
∗

C^*

-algebras are stable. We show that this is no longer true in the nonseparable context even for the most natural case of an uncountable inductive limit of an increasing chain of separable stable and AF ideals: we construct a GCR, AF (in fact, scattered) subalgebra

A

\mathcal {A}

of

B

(

ℓ
2

)

\mathcal {B}(\ell _2)

, which is the inductive limit of length

ω
1

\omega _1

of its separable stable ideals

I

α

\mathcal {I}_\alpha

(

α
>

ω
1

\alpha >\omega _1

) satisfying

I

α
+
1

/

I

α

≅

K

(

ℓ
2

)

\mathcal {I}_{\alpha +1}/\mathcal {I}_\alpha \cong \mathcal {K}(\ell _2)

for each

α
>

ω
1

\alpha >\omega _1

, while

A

\mathcal {A}

is not stable. The sequence

(

I

α

)

α
≤

ω
1

(\mathcal {I}_\alpha )_{\alpha \leq \omega _1}

is the GCR composition series of

A

\mathcal {A}

which in this case coincides with the Cantor–Bendixson composition series as a scattered

C
∗

C^*

-algebra.

A

\mathcal {A}

has the property that all of its proper two-sided ideals are listed as

I

α

\mathcal {I}_\alpha

’s for some

α
>

ω
1

\alpha >\omega _1

, and therefore the family of stable ideals of

A

\mathcal {A}

has no maximal element.

By taking

A

′

=

A

⊗

K

(

ℓ
2

)

\mathcal {A}’=\mathcal {A}\otimes \mathcal {K}(\ell _2)

we obtain a stable

C
∗

C^*

-algebra with analogous composition series

(

J

α

)

α
>

ω
1

(\mathcal {J}_\alpha )_{\alpha >\omega _1}

whose ideals

J

α

\mathcal {J}_\alpha

are isomorphic to

I

α

\mathcal {I}_\alpha

for each

α
>

ω
1

\alpha >\omega _1

. In particular, there are nonisomorphic scattered

C
∗

C^*

-algebras whose GCR composition series

(

I

α

)

α
≤

ω
1

(\mathcal {I}_\alpha )_{\alpha \leq \omega _1}

satisfy

I

α
+
1

/

I

α

≅

K

(

ℓ
2

)

\mathcal {I}_{\alpha +1}/\mathcal {I}_\alpha \cong \mathcal {K}(\ell _2)

for all

α
>

ω
1

\alpha >\omega _1

, for which the composition series differs first at

α
=

ω
1

\alpha =\omega _1

.
On the first eigenvalue of the normalized 𝑝-Laplacian
Authors: Crasta Graziano , Fragalà Ilaria , Kawohl Bernd
Published: October 2019

We prove that if

Ω
\Omega

is an open bounded domain with smooth and connected boundary, for every

p
∈
(
1
,
+
∞
)

p \in (1, + \infty )

the first Dirichlet eigenvalue of the normalized

p
p

-Laplacian is simple in the sense that two positive eigenfunctions are necessarily multiple of each other. We also give a (nonoptimal) lower bound for the eigenvalue in terms of the measure of

Ω
\Omega

, and we address the open problem of proving a Faber–Krahn-type inequality with balls as optimal domains.
Undecidability of ℚ⁽²⁾
Authors: Martínez-Ranero Carlos , Utreras Javier , Videla Carlos
Published: October 2019

It is shown that the compositum

Q

(
2
)

\mathbb {Q}^{(2)}

of all degree 2 extensions of

Q

\mathbb {Q}

has undecidable theory.
Maximally monotone operators with ranges whose closures are not convex and an answer to a recent question by Stephen Simons
Authors: Bauschke Heinz , Moursi Walaa , Wang Xianfu
Published: October 2019

In his recent Proceedings of the AMS paper, “Gossez’s skew linear map and its pathological maximally monotone multifunctions”, Stephen Simons proved that the closure of the range of the sum of the Gossez operator and a multiple of the duality map is not convex whenever the scalar is between

0
0

and

4
4

. The problem of the convexity of that range when the scalar is equal to

4
4

was explicitly stated. In this paper, we answer this question in the negative for any scalar greater than or equal to

4
4

. We derive this result from an abstract framework that allows us to also obtain a corresponding result for the Fitzpatrick-Phelps integral operator.
On two variable Beurling algebra analogues of theorems of Wiener and Lévy on Fourier series
Authors: Dabhi Prakash
Published: October 2019

Let

ω
:

Z

2

→
[
1
,
∞
)

\omega :\mathbb Z^2 \to [1,\infty )

be a weight satisfying a certain technical property. Let

f
f

be a continuous function on the torus

T

2

\mathbb T^2

such that
<mml:math xmlns:mml="http://www.w3.org/1998/Math/MathML" alttext="sigma-summation Underscript bold m element-of double-struck upper Z squared Endscripts StartAbsoluteValue ModifyingAbove f With caret left-parenthesis bold m right-parenthesis EndAbsoluteValue omega left-parenthesis bold m right-parenthesis greater-than normal infinity">

∑

m

∈

Z

2

|

f
^

(

m

)

|

ω
(

m

)
>
∞

\sum _{\mathbf {m}\in \mathbb Z^2}|\widehat f(\mathbf {m})|\omega (\mathbf {m})>\infty

. If

f
f

is nowhere vanishing on

T

2

\mathbb T^2

, then there is a weight

ν
\nu

on

Z

2

\mathbb Z^2

such that

1
≤
ν
≤
ω

1\leq \nu \leq \omega

,

ν
\nu

is nonconstant if and only if

ω
\omega

is nonconstant and
<mml:math xmlns:mml="http://www.w3.org/1998/Math/MathML" alttext="sigma-summation Underscript bold m element-of double-struck upper Z squared Endscripts StartAbsoluteValue ModifyingAbove left-parenthesis StartFraction 1 Over f EndFraction right-parenthesis With caret left-parenthesis bold m right-parenthesis EndAbsoluteValue nu left-parenthesis bold m right-parenthesis greater-than normal infinity">

∑

m

∈

Z

2

|

(

1
f

)

^

(

m

)
|

ν
(

m

)
>
∞

\sum _{\mathbf {m}\in \mathbb Z^2}\left |\widehat {(\frac {1}{f})}(\mathbf {m})\right |\nu (\mathbf {m})>\infty

. If

φ
\varphi

is holomorphic on a neighbourhood of the range of

f
f

, then there is weight

χ
\chi

on

Z

2

\mathbb Z^2

such that

1
≤
χ
≤
ω

1\leq \chi \leq \omega

,

χ
\chi

is nonconstant if and only if

ω
\omega

is nonconstant and
<mml:math xmlns:mml="http://www.w3.org/1998/Math/MathML" alttext="sigma-summation Underscript bold m element-of double-struck upper Z squared Endscripts StartAbsoluteValue ModifyingAbove left-parenthesis phi ring f right-parenthesis With caret left-parenthesis bold m right-parenthesis EndAbsoluteValue chi left-parenthesis bold m right-parenthesis greater-than normal infinity">

∑

m

∈

Z

2

|

(
φ
∘
f
)

^

(

m

)

|

χ
(

m

)
>
∞

\sum _{\mathbf {m}\in \mathbb Z^2}|\widehat {(\varphi \circ f)}(\mathbf {m})|\chi (\mathbf {m})>\infty

. An analogue of Żelazko’s theorem on

p
p

-th power convergence is also discussed. These two variables weighted analogues of classical theorems of Wiener, Lévy and Żelazko are proved exhibiting the complexity of weights in two variables.
Complex symmetric composition operators on weighted Hardy spaces
Authors: Narayan Sivaram , Sievewright Daniel , Tjani Maria
Published: October 2019

Let

φ
\varphi

be an analytic self-map of the open unit disk

D

\mathbb {D}

. We study the complex symmetry of composition operators

C
φ

C_\varphi

on weighted Hardy spaces induced by a bounded sequence. For any analytic self-map of

D

\mathbb {D}

that is not an elliptic automorphism, we establish that if

C

φ

C_{\varphi }

is complex symmetric, then either

φ
(
0
)
=
0

\varphi (0)=0

or

φ
\varphi

is linear. In the case of weighted Bergman spaces

A

α

2

A^{2}_{\alpha }

, we find the non-automorphic linear fractional symbols

φ
\varphi

such that

C

φ

C_{\varphi }

is complex symmetric.
A note on weak-star and norm Borel sets in the dual of the space of continuous functions
Authors: Ferrari S.
Published: October 2019

Let

Bo
⁡
(
T
,
τ
)

\operatorname {Bo}(T,\tau )

be the Borel

σ
\sigma

-algebra generated by the topology

τ
\tau

on

T
T

. In this paper we show that if

K
K

is a Hausdorff compact space, then every subset of

K
K

is a Borel set if and only if

\[
\operatorname {Bo}(C^*(K),\mathnormal {w}^*)=\operatorname {Bo}(C^*(K),\left \|\cdot \right \|),\]
where

\mathnormal {w}^* denotes the weak-star topology and

‖

⋅

‖

\left \|{\cdot }\right \|

is the dual norm with respect to the sup-norm on the space of real-valued continuous functions

C
(
K
)

C(K)

. Furthermore, we study the topological properties of the Hausdorff compact spaces

K
K

such that every subset is a Borel set. In particular, we show that if the axiom of choice holds true, then

K
K

is scattered.
Group Discussions and the Documentary Method in Education Research
Authors: Weller Wivian
Published: October 2019

Real groups constitute themselves as representatives of social structures, that is, of communicative processes in which it is possible to identify patterns and a certain model of communication. This model is not random or incipient, rather it documents collective experiences as well as the social characteristics of these groups, their representations of class, social environment, and generational belonging. In the context of qualitative research methods in the fields of social sciences and education, group discussions gained prominence mainly from research conducted with children and young people. As a research method, they constitute an important tool in the reconstruction of milieux and collective orientations that guide the actions of the subjects in the spaces in which they live.

This article begins with some considerations about group interviews, highlighting the Anglo-Saxon model of focus groups, the Spanish tradition of group discussions from the School of Qualitative Critics in Madrid, and group discussions conceived in the 1950s at the Frankfurt School in Germany. Next, the theoretical-methodological basis of group discussions and the documentary method developed in Germany in the 1980s by Ralf Bohnsack are presented. Both procedures are anchored mainly in Karl Mannheim’s sociology of knowledge, but also in Pierre Bourdieu’s ethnography and sociology of culture. Finally, from the results of three research projects in education carried out in Mexico, Chile, and Brazil, the potential of this research and approach to data analysis is assessed. Based on the principle of abduction, the documentary method inspires the creation of analytical instruments rooted in praxis and that can delineate educational experiences in different contexts.
Japanese Diasporas and Coffee Production
Authors: Iijima Mariko
Published: October 2019

Between the late 19th century and the first half of the 20th century, the Japanese Empire experienced outflows of its people to both its own colonies and foreign countries that were mainly located in the Asia-Pacific region. In their destinations, a majority of these migrants were engaged in physical labor in agricultural, construction, and lumbering industries. Coffee production also became a significant economic activity for many Japanese migrants in Brazil as well as some in Hawai‘i (the US territory, 1898–1959), Taiwan (the Japanese colony, 1895–1945), and Saipan (part of Nan’yō, the Japanese mandate, 1920–1945). Previously, historical studies of the Japanese migration have been focused on one-directional and one-site migrations, that is, migrations from Japan to a single destination. This is partly due to a lack of comprehensive statistical data that could enable researches to trace individual multiple-directional trajectories, and partly due to the scholastic divide of studying Japanese migrations according to destinations—whether they moved to the Japanese territories as colonial settlers or non-territories as immigrants.

This article utilizes coffee, which has a long history of being connected to global-scale movements, as an analytical lens to highlight more dynamic and multi-directional migrations of Japanese people, including those who moved from Japan, to Hawai‘i, to Saipan, and to Taiwan by being involved in coffee farming or businesses. Furthermore, this article argues that coffee functioned as an agency to connect the metropole of the Japanese Empire, which consumed coffee, and the newly established coffee farms and plantations in Japan’s Taiwan and Saipan. While the project of sending Japanese immigrants to Brazil contributed to the popularization of coffee-drinking culture in urban areas of Japan, Japanese coffee farmers in Hawai‘i played a key role in establishing coffee farms and plantations in Taiwan and Saipan from the 1920s to the 1930s. In this way, part of coffee’s trans-pacific movement was supported by the Japanese diasporic network that linked coffee-producing areas in the Asia-Pacific, where, at the same time, included the areas that absorbed a significant number of Japanese people migrants. These dynamic and trans-pacific interactions between coffee and Japanese diasporic communities indicate that migrations of Japanese people can be considered in the context of the global history of coffee and possibly, other crops and materials.
Central Africa and the Atlantic World
Authors: Ferreira Roquinaldo
Published: October 2019

Central Africa became deeply intertwined in the Atlantic world with the arrival of the Portuguese in 1482, which opened up a new world of connections between African societies and European and American partners. As a region, central Africa stretches from Gabon to Mossamedes, near the border of the present nation of Namibia. Two distinct patterns of interaction marked the region’s integration into the wider Atlantic world. On the Loango coast, Atlantic trade by Dutch, British, and French merchants favored African kings in the short term but eventually paved the way for the rise of coastal rulers who seized upon wealth amassed through the slave trade to challenge kingship. After first playing out in the kingdom of Kongo, this dynamic unfolded in several other polities, such as the kingdom of Ngoyo and Ndongo.

South of the Congo River, Portugal’s ability to carve out coastal enclaves in Luanda and Benguela powerfully shaped the relationship with the Atlantic world. Both cities developed sprawling trading networks with their immediate hinterlands as well as several cities across the Atlantic, particularly in Brazil but later also in Cuba. Although the slave trade formed the cornerstone of trading networks, a continuum of social, cultural, and political ties bridged the ocean. Portuguese institutional and economic presence was deeply dependent on Angola’s ties with Brazil. The two Portuguese colonies interacted bilaterally, and Brazil was not only the source of commodities for the trade in human beings but also in crops, food supplies, and military hardware.

Distinct patterns of Afro-European interaction in Loango and Portuguese Angola should not hide the intense trade between these two regions. Since the 17th century, Luanda had depended on the Loango coast for palm-cloth currencies (libongos) that circulated widely in the capital city of Portuguese Angola. Cabinda men sailed to Luanda to purchase tobacco and sell slaves and other goods. As the French and then the British abandoned the slave trade, the direct slave trade with Brazil intensified and altered the structure of shipments of captives. In addition to the tightening Brazilian grip over central Africa’s slave trade, this development further integrated coastal trade between Loango and Portuguese Angola and set the stage for the continuation of shipments of captives until the 1860s.
A Feminist History of Violence against Women and the LGBTQIA+ Community in Chile, 1964–2018
Authors: Hiner Hillary
Published: October 2019

From a historical perspective, violence against women and the LGBTQIA+ community (lesbian, gay, bisexual, trans, queer, intersex, asexual, and “+” for other possible associated identities) in Chile has presented itself and been understood in different ways. On the one hand, we have to take into consideration what Maria Lugones has named the “coloniality of gender” and how racism, sexism, and heteronormativity was installed from the colonial period onward, promoting specific violences against indigenous, black, lesbian, and trans women. Additionally, for a great deal of time, from roughly the colonial period until the 1990s, it was considered completely acceptable to use violence in the family and in intimate partner relationships to “correct” and punish women and girls. The Pinochet dictatorship (1973–1990) also adds another dimension to this discussion, as women were affected by gendered and sexualized state terrorism. However, the reappearance of strong women’s and feminist groups during the dictatorship also signaled a profound questioning of these types of gender violence, linking it to patriarchal structures and the need for democracy “in the country” and “in the home.” A similar effect was achieved by the emergence of LGBTQIA+ groups from the 1980s on, as they questioned the historic violence, hate crimes, and discrimination against gay men, lesbians, and, more recently, trans people. In both cases, then, pressures from social movement groups have forced the post-dictatorship Chilean state to pass laws and promote anti-violence public policy. For better and for worse, however, those anti-violence initiatives that have been most successful, in terms of visibility and public policy coverage, have generally centered on violences experienced by white-mestiza, cishet, urban women, particularly those that survive family violence. Historiographies on violence against women and the LGBTQIA+ community are relatively scarce, although there has been increased production in the last ten years, especially around the topics of women survivors of family or intimate partner violence and women survivors of torture and political prison.
Are large simple trials for dementia prevention possible?
Authors: Whiteley William N , Anand Sonia , Bangdiwala Shrikant I , Bosch Jackie , Canavan Michelle , Chertkow Howard , Gerstein Hertzel C , Gorelick Philip , O’Donnell Martin , Paré Guillaume , Pigeyre Marie , Seshadri Sudha , Sharma Mike , Smith Eric E , Williamson Jeff , Cukierman-Yaffe Tali , Hart Robert G , Yusuf Salim
Published: October 2019

New trials of dementia prevention are needed to test novel strategies and agents. Large, simple, cardiovascular trials have successfully discovered treatments with moderate but worthwhile effects to prevent heart attack and stroke. The design of these trials may hold lessons for the dementia prevention.

Here we outline suitable populations, interventions and outcomes for large simple trials in dementia prevention. We consider what features are needed to maximise efficiency. Populations could be selected by age, clinical or genetic risk factors or clinical presentation. Patients and their families prioritise functional and clinical outcomes over cognitive scores and levels of biomarkers. Loss of particular functions or dementia diagnoses therefore are most meaningful to participants and potential patients and can be measured in large trials.

The size of the population and duration of follow-up needed for dementia prevention trials will be a major challenge and will need collaboration between many clinical investigators, funders and patient organisations.
Performance Comparison of N95 and P100 Filtering Facepiece Respirators with Presence of Artificial Leakage
Authors: Zhu Jintuo , He Xinjian , Guffey Steve , Wang Liang , Wang Haifeng , Cheng Jianwei
Published: October 2019

Objectives

National Institute for Occupational Safety and Health–approved P100 filtering facepiece respirators (FFRs) have a higher filter efficiency compared to the N95 filters. However, the former typically produce higher flow resistance (Rf). Consequently, when faceseal leakage is present, the proportion of leakage airflow for P100 FFRs may exceed that of N95s, resulting in a higher total inward leakage (TIL) of the P100.

Methods

In this manikin-based study, the performance of two pairs of N95 and P100 FFRs (N95-A versus P100-A; N95-B versus P100-B) were compared under five sealing conditions (fully sealed and partially sealed with one, two, or three leaks of 0.8-mm, and one 2-mm leak). Sodium chloride particles (CMD ~45 nm) were used as the challenge aerosol. Respirators were tested under three constant flows (15, 50, and 85 L/min) and three cyclic flows (mean inspiratory flow = 15, 50, and 85 L/min). Both filter penetration (Pfilter) and TIL were determined. The Rf under constant flows was recorded. Based on Pfilter, TIL, and Rf, the quality factor (qf) was calculated to compare the overall performance of N95 and P100 FFRs.

Results

For a fully sealed condition, the Pfilter was much lower for the P100 FFRs than for the N95 FFRs. When small leaks were inserted (0.8-mm and 2 × 0.8-mm), the TIL was higher for the P100 FFRs than for the N95 FFRs under the lowest tested flow (15 L/min), while for greater leaks (3 × 0.8-mm and 2-mm), the TIL of the P100 FFRs was always higher regardless of the flow. The Rf of P100 FFRs was measured twice as high as the N95. The qf values were also found higher for the N95 FFRs than for the P100 FFRs regardless of leak size and breathing flow.

Conclusions

With the presence of artificial leakage, a P100 FFR with high-flow-resistance may not be as protective as a low-flow-resistance N95 FFR. This finding suggests that future efforts should be directed to reducing the breathing resistance when designing P100 FFRs.
Evaluation of Sorbent Sampling and Analysis Procedures for Acetone in Workplace Air: Variations of Concentration and Relative Humidity
Authors: Soo Jhy-Charm , Lebouf Ryan F , Chisholm William P , Nelson John , Roberts Jennifer , Kashon Michael L , Lee Eun Gyung , Harper Martin
Published: October 2019

This study experimentally evaluates the performance of different sorbent tubes for sampling acetone vapor in workplace air. A dynamic atmosphere system produced an acetone alone and a mixture with other analytes containing ~73, 483, and 1898 µg acetone mass loading at 25, 50, and 75% relative humidity (RH) at 25°C. Sorbent samples were analyzed in accordance with OSHA Method 69 (Carbosieve S-III) and NMAM 1501, modified to use Anasorb 747 sorbent. Both methods were modified to include the additional analytes. Additional extraction procedures with and without 1% dimethylformamide and anhydrous magnesium sulfate were included in the modified NMAM 1501 using Anasorb 747. Silica gel sorbent tubes analyzed according to NMAM 2027 were included. There were significant reductions in the recovery of acetone from both Anasorb 747 and Carbosieve S-III collected from air at 75% RH, relative to collection at 25 or 50% RH at very low loading compared with that of samples collected at mid to high loading. Silica gel provided a consistent recovery of acetone at all RHs and in the presence of other chemical interferences at 75% RH. The likely cause of mass dependence may arise from the humidity effect on acetone adsorption onto both beaded active carbon and carbon molecular sieve either in sampling or in analysis. The present study confirms not only previous observations but also adds to the literature showing carbonaceous sorbents are not well suited for sampling ketones at high humidity and low concentration.
Female solo song and duetting are associated with different territoriality in songbirds
Authors: Mikula Peter , Tószögyová Anna , Hořák David , Petrusková Tereza , Storch David , Albrecht Tomáš
Published: October 2019

Recently, there has been an increased effort to unravel selective factors behind female song evolution in songbirds. Female birds which produce songs may sing either solo or in duets; although the 2 vocal performances likely evolved through different selection forces and mechanisms, the majority of large-scale studies to date have focused only on duetting or female song in general (pooling female solo song and duetting into a single category). Hence, here we estimate the effect of behavioral life-history traits (territoriality, social bonds, and cooperative breeding) and environmental productivity on the occurrence of female solo song and duetting separately in songbirds of South Africa and Lesotho. The focal region is characterized by subtropical/tropical climate, clear spatial environmental productivity gradient, and detailed knowledge on avian species distribution and behavioral life-history traits. Phylogenetically informed comparative analyses revealed that species where females produce only solo songs exhibited higher levels of territoriality than species with nonsinging females (in an univariable model) but, simultaneously, lower levels than duetting species. Although both species with female solo song and duetting establish mainly long-term social bonds, the former defend their territories seasonally while the latter exhibit mainly year-round territoriality. Cooperative breeding and environmental productivity were not associated with the distribution of female solo song and duetting in any model. Our results indicate that when exploring female song ecology and evolution, female solo song and duetting are likely to be distinct song categories associated with different levels of territoriality.
OLOGRAM: determining significance of total overlap length between genomic regions sets
Authors: Ferré Q , Charbonnier G , Sadouni N , Lopez F , Kermezli Y , Spicuglia S , Capponi C , Ghattas B , Puthier D
Published: October 2019

Motivation

Various bioinformatics analyses provide sets of genomic coordinates of interest. Whether two such sets possess a functional relation is a frequent question. This is often determined by interpreting the statistical significance of their overlaps. However, only few existing methods consider the lengths of the overlap, and they do not provide a resolutive P-value.

Results

Here, we introduce OLOGRAM, which performs overlap statistics between sets of genomic regions described in BEDs or GTF. It uses Monte Carlo simulation, taking into account both the distributions of region and inter-region lengths, to fit a negative binomial model of the total overlap length. Exclusion of user-defined genomic areas during the shuffling is supported.

Availability and implementation

This tool is available through the command line interface of the pygtftk toolkit. It has been tested on Linux and OSX and is available on Bioconda and from https://github.com/dputhier/pygtftk under the GNU GPL license.

Supplementary information

Supplementary data are available at Bioinformatics online.
From Needs to Relationships to Organisations: Transactional Complexity in Social Work in the Swedish Social Services
Authors: Khoo Evelyn , Nygren Lennart , Gümüscü Ahmet
Published: October 2019

This article explores how Swedish social workers in different sectors of the social services understand complexity in relation to the needs found in ‘family’ and in social work practice. This study is based on interviews with sixty social workers in five service sectors: child welfare, elderly care, disability care, substance abuse and social assistance. The social workers’ reports of understanding and dealing with families with complex needs reveal distinctions between deeply rooted and broadly based needs. Complex family needs are transformed into complex cases based on family composition, relationships between clients and social workers and organisational context. Complexity theory, and in particular the term transactional complexity, is applied to describe the interactive relationship in and between complex needs, relational complexity and organisational complexity. The boundaries between these three domains are not distinct, and the interconnectivity and complexities occurring in and between them contribute to the production of much of the ‘wickedness’ that exists in social work practice. Social workers may gain from this knowledge in order to unravel the often intangible complexity that commonly appears in social work with families.
Clinical status and evolution in moyamoya: which angiographic findings correlate?
Authors: Rosi Andrea , Riordan Coleman P , Smith Edward R , Scott R Michael , Orbach Darren B
Published: October 2019

Moyamoya is a progressive steno-occlusive cerebrovascular pathology of unknown aetiology that usually involves the terminal portions of the internal carotid arteries and/or the proximal portions of the anterior and middle cerebral arteries bilaterally. The pre-operative Suzuki staging system and post-operative Matsushima grade are nearly universally used markers of natural history and surgical revascularization results, respectively, but their correlation with clinical and radiographic manifestations of moyamoya has not been systematically evaluated in a large cohort. This study evaluated the strength of correlations between pre- and post-operative angiographic parameters and clinical status among paediatric patients with moyamoya. The participants included 58 patients of mean age 11 years at the time of surgery who underwent bilateral indirect revascularization in the same procedure at Boston Children’s Hospital, between January 2010 and December 2015. All included patients had available pre-operative and 1-year post-operative digital subtraction angiography. Clinical data included presenting symptoms, degree of functional incapacity, and peri-operative and long-term complications. Radiographic data included pre-operative Suzuki stage, degree of arterial stenosis, a novel collateral score, the presence of hypovascular territories on digital subtraction angiography, and post-operative Matsushima grade and evolution of stenosis. Chi-squared test and Pearson coefficient were used for correlation studies for categorical variables and Spearman’s rho was used for correlation studies for continuous variables. Results showed that Suzuki stage, collateral score and degree of stenosis were insufficient to predict clinical presentation, pre-operative incapacity and radiographic presentation, whereas the presence of hypovascular territories was correlated with all of these. At 1-year follow-up, Matsushima grade was insufficient for predicting peri-operative or long-term complications, nor did it correlate with post-operative incapacity. The presence of hypovascular territories at 1-year follow-up was correlated with the incidence of post-operative ischaemic symptoms.
Variation in esophageal anastomosis technique—the role of collaborative learning
Authors: Halliday L J , Doran S L F , Sgromo B , Viswanath Y K S , Tucker O , Patel B , Jambulingam P S , Dawas K , Mercer S , Baker C , Mughal M , Hanna G B , Moorthy K
Published: October 2019

Centralization of care has improved outcomes in esophagogastric (EG) cancer surgery. However, specialist surgical centers often work within clinical silos, with little transfer of knowledge and experience. Although variation exists in multiple dimensions of perioperative care, the differences in operative technique are rarely studied. An esophageal anastomosis workshop was held to identify areas of common and differing practice within the operative technique. Surgeons showed videos of their anastomosis technique by open and minimally invasive surgery. Each video was followed by a discussion. Surgeons from 10 different EG cancer centers attended. Eight key technical differences and learning points were identified and discussed: the optimum diameter of the gastric conduit; avoiding ischemia in the gastric conduit; minimizing esophageal trauma; the use of an esophageal mucosal collar; omental wrapping; intraoperative leak testing; ideal diameter of the circular stapler and the growing use of linear stapled anastomoses. The workshop received positive feedback from participants and on 2 years follow-up, 40% stated that they believed that the learning of tips and techniques during the workshop has contributed to lowering their anastomotic leak rate. Many differences exist in surgical technique. The reasons for, and crucially the significance of, these differences must be discussed and examined. Workshops provide a forum for peer-to-peer collaborative learning to reflect on one’s own practice and improve surgical technique. These changes can, in turn, generate incremental improvements in patient care and postoperative outcomes.
Effects of Strip Tillage in Sugar Beet on Density and Richness of Predatory Arthropods
Authors: Wenninger Erik J , Vogt Jessica R , Lojewski Jeffrey , Neher Oliver T , Morishita Don W , Daku Kristin E
Published: October 2019

Strip tillage, in which tillage and seedbed preparation are limited to a narrow band where the subsequent crop is planted, provides many potential agronomic benefits, including reduced fuel and labor costs, reduced erosion, and improved soil tilth. Lower soil disturbance and enhanced water retention associated with strip tillage also may affect density and diversity of predatory arthropods, which have been little studied in sugar beet. We examined the effects of tillage (conventional versus strip) on the predatory epigeal arthropod fauna in sugar beet. Studies were conducted over three growing seasons (2010–2012) in Idaho using both fenced and unfenced pitfall traps to sample arthropods. Unfenced pitfall traps often captured a greater activity density and richness of predators, and showed no bias of higher captures in conventionally tilled plots as has been shown elsewhere. Total density of predators was higher in strip tillage only during 2011. Density and species richness of carabid beetles did not differ between tillage treatments during the course of the study. Density of the other major taxa (staphylinid beetles, spiders, and Opiliones) was higher under strip tillage during some years, especially early in the season, but richness showed little or no relationship with tillage. Predaceous arthropods might be favored by enhanced ground cover, higher humidity, more moderate temperatures, and/or less habitat disturbance associated with strip-tilled plots. The results suggest that certain groups of soil-dwelling predatory arthropods can be favored by strip tillage in sugar beet, which further adds to the benefits of conservation tillage in this system.
Transient appearance of Brugada-like Type 1 electrocardiogram pattern immediately after biphasic synchronized electrical cardioversion for atrial fibrillation: a case series
Authors: Abdalla Khalid A S , Sorgente Antonio , Brugada Pedro
Published: October 2019

Background

ST-segment deviation post-electrical cardioversion is a common finding amongst a significant number of patients. However, the mechanism by which this phenomenon occurs and its clinical implications are not fully understood.

Case summary

Four patients presented to our department with complaints of palpitations. They were found to have atrial fibrillation and were cardioverted using a synchronized direct current shock at 200 J. However, their telemetry immediately after the shock showed transiently an ST-segment elevation resembling Brugada Type 1 pattern. All telemetries normalized within 6 s from cardioversion.

Discussion

Through this report, we aim to raise mild concern about a possible safety issue related to synchronized electrical cardioversion with electrodes positioned in an anteroposterior fashion. Also, we try to give a pathophysiological explanation to this finding on the base of the knowledge accumulated through the years on Brugada syndrome.
Ventricular fibrillation in congenitally corrected transposition of great arteries treated with pacing: a case report
Authors: Zhang Lei , Liu Hongyang , Wan Qilin , Han Xinqiang
Published: October 2019

Background

Congenitally corrected transposition of the great arteries (CCTGA) is a rare form of congenital heart disease which may present with sudden death from malignant arrhythmias including complete heart block and ventricular tachyarrhythmias as late complications. Only few cases about ventricular tachyarrhythmias, usually in those with markedly depressed systemic ventricular function, have been reported.

Case summary

A 26-year-old woman with a known history of CCTGA presented to the emergency department with palpitations and breathlessness for 3–4 weeks and worsening symptoms for 8 h. She had a history of ventricular septal defect repair 14 years ago. Her initial presentation electrocardiogram demonstrated high degree atrioventricular block with a ventricular rate of 44 b.p.m. She had two episodes of complete syncope during this hospitalization, both required external defibrillation due to documented bradycardia-dependent ventricular fibrillations. Her two-dimensional echocardiography study confirmed the diagnosis of CCTGA with preserved systolic ventricular function. She underwent urgent temporal pacing wire placement with a paced ventricular rate at 90 b.p.m. Having thoroughly reviewed the arrhythmia events and discussed with the patient about the option of defibrillator vs. pacemaker therapy a decision was made upon her request for dual-chamber pacemaker implantation. She was discharged home uneventfully 3 days after hospital presentation and has been physically active at 3-, 6-, and 9-month follow-ups.

Discussion

Our case illustrates the individualized clinical decision making in choosing device therapy for a rare congenital heart disease presented with malignant arrhythmia. Careful history taking, open communication, and closely planned long-term follow-up will be essential in caring for such patients.
International Delphi survey of the ESTS/AATS/ISTH task force on venous thromboembolism prophylaxis in thoracic surgery: the role of extended post-discharge prophylaxis
Authors: Agzarian John , Litle Virginia , Linkins Lori-Ann , Brunelli Alessandro , Schneider Laura , Kestenholz Peter , Li Hui , Rocco Gaetano , Girard Philippe , Nakajima Jun , Samama Charles Marc , Scarci Marco , Anraku Masaki , Falcoz Pierre-Emmanuel , Bertolaccini Luca , Lin Jules , Murthy Sudish , Hofstetter Wayne , Okumura Meinoshin , Solli Piergiorgio , Minervini Fabrizio , Kirk Alan , Douketis James , Shargall Yaron
Published: October 2019

OBJECTIVES

Venous thromboembolic events can be successfully prevented with chemical and/or mechanical prophylaxis measures, but evidence-based guidelines in thoracic surgery are limited, particularly regarding extended post-discharge prophylaxis. This study attempts to gather an international consensus on best practices to inform the development of such guidelines.

METHODS

A series of 3 surveys was distributed to the ESTS/AATS/ISTH (European Society of Thoracic Surgeons, American Association of Thoracic Surgeons, International Society for Thrombosis and Haemostasis) venous thromboembolic events prophylaxis working group starting January 2017. This iterative Delphi consensus process sought to gather a consensus on (i) risk factors; (ii) preferred agents; (iii) duration; and (iv) perceived barriers to an extended thromboprophylaxis approach. Participant responses were expressed on a 10-point scale, and the results were summarized and circulated to all respondents in subsequent rounds. A coefficient of variance of ≤0.3 was identified pre hoc to identify agreement.

RESULTS

A total of 21 Working Group members completed the surveys, composed of 19% non-surgeon thrombosis experts, and 48% from North America. Respondents largely saw agreement regarding risk factors that indicate a need for extended thromboprophylaxis. The group agreed that low-molecular-weight heparin is a suitable agent for use post-discharge, but there was a wide variety in response regarding agents, duration and barriers to extended prophylaxis, where no consensus was observed across the three rounds.

CONCLUSIONS

There is strong agreement around indications for extended venous thromboembolic events thromboprophylaxis after thoracic surgery, but there is little consensus regarding the agents and duration to be employed. Further research is required to better inform guideline development.
The impact of decriminalization on marijuana and alcohol consumption in Jamaica
Authors: Spencer Nekeisha , Strobl Eric
Published: October 2019

We examine whether marijuana decriminalization in Jamaica, a country that historically has had relatively widespread use of the drug, has led to an increase in its use, the frequency of use and the money spent on it. To this end, we use a national drug survey dataset with extensive information on people’s use of, attitudes towards, access to marijuana. Our econometric analysis shows that awareness of the legislation has a positive correlation with the use of the substance. Worryingly, decriminalization positively correlates with the likelihood of first time and general use for youths. There is also some evidence that the legislation results in a substitution away from alcohol towards marijuana consumption for youths. From a policy perspective, a marijuana monitoring system can be implemented to follow the consumption patterns of youths. This should involve establishing school-level programmes that monitor students, and where potential drug users are identified, school officials should intervene to curb students’ drug appetite before an escalated use of marijuana.
The Impact of State Firearm Laws on Homicide Rates among Black and White Populations in the United States, 1991–2016
Authors: Knopov Anita , Siegel Michael , Xuan Ziming , Rothman Emily F , Cronin Shea W , Hemenway David
Published: October 2019

This study aimed to investigate the potential differential effects of state-level firearm laws on black and white populations. Using a panel design, authors examined the relationship between state firearm laws and homicide victimization rates among white people and black people in 39 states during the period between 1991 and 2016. Authors modeled homicide rates using linear regression with year and state fixed effects and controlled for a range of time-varying, state-level factors. Results showed that universal background check laws and permit requirement laws were associated with lower homicide rates among both white and black populations, and “shall issue” laws were associated with higher homicide rates among both white and black populations. Laws that prohibit firearm possession among people convicted of a violent misdemeanor or require relinquishment of firearms by people with a domestic violence restraining order were associated with lower black homicide rates, but not with white homicide rates. Author identification of heterogeneity in the associations between state firearm laws and homicide rates among different racial groups has implications for reducing racial health disparities.
Safety of Biologic Therapy in Liver Transplant Recipients: Case Closed?
Authors: Davis Brian C
Published: October 2019

Patients with inflammatory bowel disease who undergo liver transplantation may be considered for biologic therapy, but providers should closely monitor for infections such as cholangitis and Clostridioides difficile infection. Further research in prospective registries with long-term outcomes is needed.
On the Pronunciation Dictionaries of Contemporary German: The Concepts of Phonetic Standard and Differences in Specific Phonetic Issues
Authors: Nycz Krzysztof , Tęcza Zygmunt
Published: October 2019

The aim of the following paper is to discuss some phonetics-based differences between four modern pronunciation dictionaries of the German language: Großes Wörterbuch der deutschen Aussprache (1982), Deutsches Aussprachewörterbuch (2009), DUDEN Aussprachewörterbuch (2000) and DUDEN Aussprachewörterbuch (2015). First, attention is paid to the concept of phonetic standard declared by the respective dictionary authors. After that, a number of specific phonetic issues are outlined which pinpoint some striking divergences between the dictionaries under analysis. The divergences occur in description and interpretation of certain phenomena in the field of vowels (diphthongs, half-long vowels, vocalic reductions), consonants (the /r/ allophones, affricates, consonant assimilations) as well as suprasegmental features (word stress marking).
Assessing the adherence to guidelines in the management of croup in Australian children: a population-based sample survey
Authors: Prentice Bernadette , Moloney Susan , Hort Jason , Hibbert Peter , Wiles Louise K , Molloy Charlotte J , Arnolda Gaston , Ting Hsuen P , Braithwaite Jeffrey , Jaffe Adam
Published: October 2019

Objective

To determine the extent to which care received by Australian children presenting with croup is in agreement with Clinical Practice Guidelines (CPGs).

Design

Retrospective population-based sample survey. Croup clinical indicators were derived from CPGs.

Data sources/study setting

Medical records from three healthcare settings were sampled for selected visits in 2012 and 2013 in three Australian states.

Data collection

Data were collected by nine experienced paediatric nurses, trained to assess eligibility for indicator assessment and adherence to CPGs. Surveyors undertook criterion-based medical record reviews using an electronic data collection tool.

Results

Documented guideline adherence was lower for general practitioners (65.9%; 95% CI: 60.8–70.6) than emergency departments (91.1%; 95% CI: 89.5–92.5) and inpatient admissions (91.3%; 95% CI: 88.1–93.9). Overall adherence was very low for a bundle of 10 indicators related to assessment (4.5%; 95% CI: 2.4–7.6) but higher for a bundle of four indicators relating to the avoidance of inappropriate therapy (83.1%; 95% CI: 59.5–96.0).

Conclusions

Most visits for croup were characterized by appropriate treatment in all healthcare settings. However, most children had limited documented clinical assessments, and some had unnecessary tests or inappropriate therapy, which has potential quality and cost implications. Universal CPG and clinical assessment tools may increase clinical consistency.