This book includes 13 papers concerning some of the recent progress in the theory of function spaces and its applications. The involved function spaces include Morrey and weak Morrey spaces, ...Hardy-type spaces, John–Nirenberg spaces, Sobolev spaces, and Besov and Triebel–Lizorkin spaces on different underlying spaces, and they are applied in the study of problems ranging from harmonic analysis to potential analysis and partial differential equations, such as the boundedness of paraproducts and Calderón operators, the characterization of pointwise multipliers, estimates of anisotropic logarithmic potential, as well as certain Dirichlet problems for the Schrödinger equation.
Projective versions of selection principles Bonanzinga, Maddalena; Cammaroto, Filippo; Matveev, Mikhail
Topology and its applications,
04/2010, Letnik:
157, Številka:
5
Journal Article
Recenzirano
Odprti dostop
All spaces are assumed to be Tychonoff. A space
X is called projectively
P
(where
P
is a topological property) if every continuous second countable image of
X is
P
. Characterizations of projectively ...Menger spaces
X in terms of continuous mappings
f
:
X
→
R
ω
, of Menger base property with respect to separable pseudometrics and a selection principle restricted to countable covers by cozero sets are given. If all finite powers of
X are projectively Menger, then all countable subspaces of
C
p
(
X
)
have countable fan tightness. The class of projectively Menger spaces contains all Menger spaces as well as all
σ-pseudocompact spaces, and all spaces of cardinality less than
d
. Projective versions of Hurewicz, Rothberger and other selection principles satisfy properties similar to the properties of projectively Menger spaces, as well as some specific properties. Thus,
X is projectively Hurewicz iff
C
p
(
X
)
has the Monotonic Sequence Selection Property in the sense of Scheepers;
βX is Rothberger iff
X is pseudocompact and projectively Rothberger. Embeddability of the countable fan space
V
ω
into
C
p
(
X
)
or
C
p
(
X
,
2
)
is characterized in terms of projective properties of
X.
To understand the health impact of long-duration spaceflight, one identical twin astronaut was monitored before, during, and after a 1-year mission onboard the International Space Station; his twin ...served as a genetically matched ground control. Longitudinal assessments identified spaceflight-specific changes, including decreased body mass, telomere elongation, genome instability, carotid artery distension and increased intima-media thickness, altered ocular structure, transcriptional and metabolic changes, DNA methylation changes in immune and oxidative stress-related pathways, gastrointestinal microbiota alterations, and some cognitive decline postflight. Although average telomere length, global gene expression, and microbiome changes returned to near preflight levels within 6 months after return to Earth, increased numbers of short telomeres were observed and expression of some genes was still disrupted. These multiomic, molecular, physiological, and behavioral datasets provide a valuable roadmap of the putative health risks for future human spaceflight.
Awake craniotomy (AC) is a common neurosurgical procedure for the resection of lesions in eloquent brain areas, which has the advantage of avoiding general anesthesia to reduce associated ...complications and costs. A significant resource limitation in low- and middle-income countries constrains the usage of AC.
To review the published literature on AC in African countries, identify challenges, and propose pragmatic solutions by practicing neurosurgeons in Africa.
We conducted a scoping review under Preferred Reporting Items for Systematic Reviews and Meta-Analysis-Scoping Review guidelines across 3 databases (PubMed, Scopus, and Web of Science). English articles investigating AC in Africa were included.
Nineteen studies consisting of 396 patients were included. Egypt was the most represented country with 8 studies (42.1%), followed by Nigeria with 6 records (31.6%). Glioma was the most common lesion type, corresponding to 120 of 396 patients (30.3%), followed by epilepsy in 71 patients (17.9%). Awake-awake-awake was the most common protocol used in 7 studies (36.8%). Sixteen studies (84.2%) contained adult patients. The youngest reported AC patient was 11 years old, whereas the oldest one was 92. Nine studies (47.4%) reported infrastructure limitations for performing AC, including the lack of funding, intraoperative monitoring equipment, imaging, medications, and limited human resources.
Despite many constraints, AC is being safely performed in low-resource settings. International collaborations among centers are a move forward, but adequate resources and management are essential to make AC an accessible procedure in many more African neurosurgical centers.
This book examines the drivers behind great power security competition in space to determine whether realistic strategic alternatives exist to further militarization.
Space is an area of increasing ...economic and military competition. This book offers an analysis of actions and events indicative of a growing security dilemma in space, which is generating an intensifying arms race between the US, China, and Russia. It explores the dynamics behind a potential future war in space and investigates methods of preventing an arms race from an international relations theory and military-strategy standpoint. The book is divided into three parts: the first section offers a broad discussion of the applicability of international relations theory to current conditions in space; the second is a direct application of theory to the space environment to determine whether competition or cooperation is the optimal strategic choice; the third section focuses on testing the hypotheses against reality, by analyzing novel alternatives to three major categories of space systems. The volume concludes with a study of the practical limitations of applying a strategy centered on commercialization as a method of defusing the orbital security dilemma.
This book will be of interest to students of space power, strategic studies, and international relations.
Building Modern Turkeyoffers a critical account of how the built environment mediated Turkey's transition from a pluralistic (multiethnic and multireligious) empire into a modern, homogenized ...nation-state following the collapse of the Ottoman Empire at the end of World War I. Zeynep Kezer argues that the deliberate dismantling of ethnic and religious enclaves and the spatial practices that ensued were as integral to conjuring up a sense of national unity and facilitating the operations of a modern nation-state as were the creation of a new capital, Ankara, and other sites and services that embodied a new modern way of life. The book breaks new ground by examining both the creative and destructive forces at play in the making of modern Turkey and by addressing the overwhelming frictions during this profound transformation and their long-term consequences. By considering spatial transformations at different scales-from the experience of the individual self in space to that of international geopolitical disputes-Kezer also illuminates the concrete and performative dimensions of fortifying a political ideology, one that instills in the population a sense of membership in and allegiance to the nation above all competing loyalties and ensures its longevity.
The Space Age began just as the struggle for civil rights forced Americans to confront the long and bitter legacy of slavery, discrimination, and violence against African Americans. Presidents John ...F. Kennedy and Lyndon Johnson utilized the space program as an agent for social change, using federal equal employment opportunity laws to open workplaces at NASA and NASA contractors to African Americans while creating thousands of research and technology jobs in the Deep South to ameliorate poverty. We Could Not Fail tells the inspiring, largely unknown story of how shooting for the stars helped to overcome segregation on earth. Richard Paul and Steven Moss profile ten pioneer African American space workers whose stories illustrate the role NASA and the space program played in promoting civil rights. They recount how these technicians, mathematicians, engineers, and an astronaut candidate surmounted barriers to move, in some cases literally, from the cotton fields to the launching pad. The authors vividly describe what it was like to be the sole African American in a NASA work group and how these brave and determined men also helped to transform Southern society by integrating colleges, patenting new inventions, holding elective office, and reviving and governing defunct towns. Adding new names to the roster of civil rights heroes and a new chapter to the story of space exploration, We Could Not Fail demonstrates how African Americans broke the color barrier by competing successfully at the highest level of American intellectual and technological achievement.
In this paper, the authors characterize, in terms of pointwise inequalities, the classical Besov spaces
B
˙
p
,
q
s
and Triebel–Lizorkin spaces
F
˙
p
,
q
s
for all
s
∈
(
0
,
1
)
and
p
,
q
∈
(
n
/
(
n
...+
s
)
,
∞
, both in
R
n
and in the metric measure spaces enjoying the doubling and reverse doubling properties. Applying this characterization, the authors prove that quasiconformal mappings preserve
F
˙
n
/
s
,
q
s
on
R
n
for all
s
∈
(
0
,
1
)
and
q
∈
(
n
/
(
n
+
s
)
,
∞
. A metric measure space version of the above morphism property is also established.
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