422 research outputs found
Diabatic and adiabatic transitions between Floquet states imprinted in coherent exciton emission in monolayer WSe₂
光を着た電子状態の飛び移りを世界で初めて観測に成功 --赤外光パルスによる電子状態制御へ--. 京都大学プレスリリース. 2022-12-28.Floquet engineering is a promising way of controlling quantum system with photon-dressed states on an ultrafast time scale. So far, the energy structure of Floquet states in solids has been intensively investigated. However, the dynamical aspects of the photon-dressed states under ultrashort pulse have not been explored yet. Their dynamics become highly sensitive to the driving field transients, and thus, understanding them is crucial for ultrafast manipulation of a quantum state. Here, we observed the coherent exciton emission in monolayer WSe₂ at room temperature at the appropriate photon energy and the field strength of the driving light pulse using high-harmonic spectroscopy. Together with numerical calculations, our measurements revealed that the coherent exciton emission spectrum reflects the diabatic and adiabatic dynamics of Floquet states of excitons. Our results provide a previosuly unexplored approach to Floquet engineering and lead to control of quantum materials through pulse shaping of the driving field
Simplified stress analysis on the temporomandibular joint in Class III patients with and without mandibular asymmetry using a rigid body spring model
金沢大学医薬保健研究域医学系To cite this article: Ueki K, Takeuchi N, Nakagawa K, Yamamoto E: Simplified stress analysis on the temporomandibular joint in Class III patients with and without mandibular asymmetry using a rigid body spring model Orthod Craniofac Res 2009;12:312-318 Structured AbstractAuthors - Ueki K, Takeuchi N, Nakagawa K, Yamamoto E Objective - Aim of this study was to investigate the differences in stress on the temporomandibular joint (TMJ) between Class III patients with and without mandibular asymmetry using a rigid body spring model (RBSM). Design - Menton (Me), the centre point of occlusal force on the line that connected the bilateral buccal cusps of the second molars and the most lateral, superior and medial points of the condyle were plotted on frontal cephalograms, and stress on the condyles was calculated with the 2-dimensional RBSM program of fortran. Setting and Sample Population - Eighty Japanese patients with diagnosed mandibular prognathism were divided into two groups, a symmetry group and asymmetry group on the basis of the Mx-Md midline position. Outcome measure - The degree (force partition) of the resultant force, the direction (angulation) and displacement (X, Y) of each condyle were calculated. The horizontal displacement vector (u), the vertical displacement vector (v) and rotation angle (θ) of the mandibular body at Menton were also calculated. Results - There were significant differences between the deviated and non-deviated sides of both groups regarding resultant force (symmetry group: p = 0.0372, asymmetry group: p = 0.0054), X (symmetry group: p < 0.0001, asymmetry group: p = 0.0001) and Y (symmetry group: p = 0.0354, asymmetry group: p = 0.0043). For angulation, there was a significant difference between the deviated and non-deviated sides in the asymmetry group (p = 0.0095). Conclusion - The results of this study suggest that difference in stress angulation on the condyles could be associated with asymmetry in mandibular prognathism. © 2009 John Wiley & Sons A/S
Classical and Quantum Cosmology of Multigravity
Recently, a multigraviton theory on a simple closed circuit graph
corresponding to the discretization of compactification of the
Kaluza-Klein (KK) theory has been considered. In the present paper, we extend
this theory to that on a general graph and study what modes of particles are
included. Furthermore, we generalize it in a possible nonlinear theory based on
the vierbein formalism and study classical and quantum cosmological solutions
in the theory. We found that scale factors in a solution for this theory repeat
acceleration and deceleration.Comment: 17 pages, 15 figures, RevTeX4.1, revised versio
Cholesterol- and actin-centered view of the plasma membrane: updating the Singer–Nicolson fluid mosaic model to commemorate its 50th anniversary
Two very polarized views exist for understanding the cellular plasma membrane (PM). For some, it is the simple fluid described by the original Singer–Nicolson fluid mosaic model. For others, due to the presence of thousands of molecular species that extensively interact with each other, the PM forms various clusters and domains that are constantly changing and therefore, no simple rules exist that can explain the structure and molecular dynamics of the PM. In this article, we propose that viewing the PM from its two predominant components, cholesterol and actin filaments, provides an excellent and transparent perspective of PM organization, dynamics, and mechanisms for its functions. We focus on the actin-induced membrane compartmentalization and lipid raft domains coexisting in the PM and how they interact with each other to perform PM functions. This view provides an important update of the fluid mosaic model
Immunohistochemical Analysis of Connexin43 Expression in Infertile Human Testes
Connexin43 (Cx43) is abundantly expressed in mammalian testes and implicated in the regulation of cell-to-cell interaction between germ cells and Sertoli cells, which is essential to the normal process of spermatogenesis. In the present study, we investigated the relation between Cx43 expression and the degree of spermatogenesis in infertile human testes. Immunohistochemical analysis of Cx43 was performed on testicular biopsies from 29 patients with azoospermia (n=23) and severe oligospermia (n=6), who gave informed consent to this experiment. The degree of testicular spermatogenesis was evaluated by Johnsen score. In the interstitium, immunostaining for Cx43 was localized to some focal parts of plasma membrane between neighboring Leydig cells. In seminiferous tubules with normal spermatogenesis, Cx43 expression was found between Sertoli cells and germ cells. However, Cx43 expression in maturation arrest was decreased and located mainly in the basal compartment of seminiferous tubules. Finally, there was a significant positive correlation between histological score of spermatogenesis and intensity of Cx43 (p=0.0294). These data suggest that the alteration of Cx43 expression may be involved in spermatogenic impairment, and that the communication between Sertoli cells and germ cells through Cx43 may be important for maturation of spermatogenesis
Efficacy and safety of systemic chemotherapy and intra-arterial chemotherapy with/without radiotherapy for bladder preservation or as neo-adjuvant therapy in patients with muscle-invasive bladder cancer: A single-centre study of 163 patients
Introduction Patients with muscle-invasive bladder cancer (MIBC) often undergo various preoperative treatments to improve survival; however, their efficacy and safety remain unclear. Materials and methods The anti-tumour effects and adverse events were evaluated in 163 MIBC patients who received systemic chemotherapy (SC, n = 34), intra-arterial chemotherapy (IAC, n = 50), or combined IAC and radiotherapy (IAC + R, n = 79). Results Pathological complete responses were observed in 17.6%, 22.0%, and 43.0% of patients in the SC, IAC, and IAC + R groups, respectively, with respective 5-year overall survival rates of 42.0%, 46.7%, and 50.3%. Multivariate analysis showed that successful IAC + R protocol administration was a significant predictor for survival (hazard ratio = 0.16, p = 0.028). The incidence of severe adverse events was higher in the IAC + R group (36.7%) than in the SC (9.8%) and IAC groups (16.0%). Conclusions IAC + R was useful for patients with MIBC. Successful completion and optimal patient selection were important for this treatment strategy
Stepping Beyond the Newtonian Paradigm in Biology. Towards an Integrable Model of Life: Accelerating Discovery in the Biological Foundations of Science
The INBIOSA project brings together a group of experts across many disciplines
who believe that science requires a revolutionary transformative
step in order to address many of the vexing challenges presented by the
world. It is INBIOSA’s purpose to enable the focused collaboration of an
interdisciplinary community of original thinkers.
This paper sets out the case for support for this effort. The focus of the
transformative research program proposal is biology-centric. We admit
that biology to date has been more fact-oriented and less theoretical than
physics. However, the key leverageable idea is that careful extension of the
science of living systems can be more effectively applied to some of our
most vexing modern problems than the prevailing scheme, derived from
abstractions in physics. While these have some universal application and
demonstrate computational advantages, they are not theoretically mandated
for the living. A new set of mathematical abstractions derived from biology
can now be similarly extended. This is made possible by leveraging
new formal tools to understand abstraction and enable computability. [The
latter has a much expanded meaning in our context from the one known
and used in computer science and biology today, that is "by rote algorithmic
means", since it is not known if a living system is computable in this
sense (Mossio et al., 2009).] Two major challenges constitute the effort.
The first challenge is to design an original general system of abstractions
within the biological domain. The initial issue is descriptive leading to the
explanatory. There has not yet been a serious formal examination of the
abstractions of the biological domain. What is used today is an amalgam;
much is inherited from physics (via the bridging abstractions of chemistry)
and there are many new abstractions from advances in mathematics (incentivized
by the need for more capable computational analyses). Interspersed
are abstractions, concepts and underlying assumptions “native” to biology
and distinct from the mechanical language of physics and computation as
we know them. A pressing agenda should be to single out the most concrete
and at the same time the most fundamental process-units in biology
and to recruit them into the descriptive domain. Therefore, the first challenge
is to build a coherent formal system of abstractions and operations
that is truly native to living systems.
Nothing will be thrown away, but many common methods will be philosophically
recast, just as in physics relativity subsumed and reinterpreted
Newtonian mechanics.
This step is required because we need a comprehensible, formal system to
apply in many domains. Emphasis should be placed on the distinction between
multi-perspective analysis and synthesis and on what could be the
basic terms or tools needed.
The second challenge is relatively simple: the actual application of this set
of biology-centric ways and means to cross-disciplinary problems. In its
early stages, this will seem to be a “new science”.
This White Paper sets out the case of continuing support of Information
and Communication Technology (ICT) for transformative research in biology
and information processing centered on paradigm changes in the epistemological,
ontological, mathematical and computational bases of the science
of living systems. Today, curiously, living systems cannot be said to
be anything more than dissipative structures organized internally by genetic
information. There is not anything substantially different from abiotic
systems other than the empirical nature of their robustness. We believe that
there are other new and unique properties and patterns comprehensible at
this bio-logical level. The report lays out a fundamental set of approaches
to articulate these properties and patterns, and is composed as follows.
Sections 1 through 4 (preamble, introduction, motivation and major biomathematical
problems) are incipient. Section 5 describes the issues affecting
Integral Biomathics and Section 6 -- the aspects of the Grand Challenge
we face with this project. Section 7 contemplates the effort to
formalize a General Theory of Living Systems (GTLS) from what we have
today. The goal is to have a formal system, equivalent to that which exists
in the physics community. Here we define how to perceive the role of time
in biology. Section 8 describes the initial efforts to apply this general theory
of living systems in many domains, with special emphasis on crossdisciplinary
problems and multiple domains spanning both “hard” and
“soft” sciences. The expected result is a coherent collection of integrated
mathematical techniques. Section 9 discusses the first two test cases, project
proposals, of our approach. They are designed to demonstrate the ability
of our approach to address “wicked problems” which span across physics,
chemistry, biology, societies and societal dynamics. The solutions
require integrated measurable results at multiple levels known as “grand
challenges” to existing methods. Finally, Section 10 adheres to an appeal
for action, advocating the necessity for further long-term support of the
INBIOSA program.
The report is concluded with preliminary non-exclusive list of challenging
research themes to address, as well as required administrative actions. The
efforts described in the ten sections of this White Paper will proceed concurrently.
Collectively, they describe a program that can be managed and
measured as it progresses
Impact of surgical adhesion barrier on significant adhesion during a repeat cesarean section
Background: Post-cesarean adhesions are associated with delayed infant delivery and infertility. In this retrospective study, we analyzed the effects of hyaluronic acid- carboxymethylcellulose (HA/CMC) membranes on postoperative adhesion during cesarean section. Methods: Sixty-seven patients were divided into the surgical adhesion barrier used (n = 28) and not-used group (n = 39). We compared the severity of adhesion at the repeat cesarean section, as well the following variables: operation and incision delivery time, blood loss, and postoperative infection between both groups. The severity of adhesion was analyzed using the Zühike’s adhesion score between the abdominal wall and uterine corpus, and the Steinleitner’s uterine adhesion score. Results: We found that the Zühike’s adhesion score between the abdominal wall and corpus of the uterus in the surgical adhesion barrier used group was significantly lower than that of the not-used group (0.46 ± 0.2 and 1.0 ± 0.2, respectively) (p = 0.04). The Steinleitner’s uterine adhesion score of the surgical adhesion barrier used group was lower than that of the not-used group (0.5 ± 0.3 and 1.3 ± 0.3, respectively), but not significantly (p = 0.07). Discussion: We concluded that the surgical adhesion barrier was effective in preventing postoperative adhesion formation during cesarean sections. However, further investigations are necessary to reveal the usefulness of the surgical adhesion barrier during cesarean section, including its cost-effectiveness
Impact of Education and Network for Avian Influenza H5N1 in Human: Knowledge, Clinical Practice, and Motivation on Medical Providers in Vietnam
BACKGROUND: Knowledge, clinical practice, and professional motivation of medical providers relating to H5N1 infection have an important influence on care for H5N1 patients who require early diagnosis and early medical intervention. METHODS/PRINCIPAL FINDINGS: Novel educational programs including training and workshops for medical providers relating to H5N1 infection in Vietnam were originally created and implemented in 18 provincial hospitals in northern Vietnam between 2008 and 2010. A self-administered, structured questionnaire survey was conducted in 8 provincial hospitals where both educational training and workshops were previously provided. A total of 326 medical providers, including physicians, nurses, and laboratory technicians who attended or did not attend original programs were enrolled in the survey. Knowledge, clinical attitudes and practice (KAP), including motivation surrounding caring for H5N1 patients, were evaluated. The study indicated a high level of knowledge and motivation in all professional groups, with especially high levels in laboratory technicians. Conferences and educational programs were evaluated to be the main scientific information resources for physicians, along with information from colleagues. The chest radiographs and the initiation of antiviral treatment in the absence of RT-PCR result were identified as gaps in education. Factors possibly influencing professional motivation for caring for H5N1 patients included healthcare profession, the hospital where the respondents worked, age group, attendance at original educational programs and at educational programs which were conducted by international health-related organizations. CONCLUSIONS: Educational programs provide high knowledge and motivation for medical providers in Vietnam caring for H5N1 patients. Additional educational programs related to chest radiographs and an initiation of treatment in the absence of RT-PCR are needed. Networking is also necessary for sharing updated scientific information and practical experiences. These enhanced KAPs by educational programs and integrated systems among hospitals should result in appropriate care for H5N1 patients and may reduce morbidity and mortality
The Sulfur Microbial Diet and Risk of Colorectal Cancer by Molecular Subtypes and Intratumoral Microbial Species in Adult Men
INTRODUCTION: We recently described the sulfur microbial diet, a pattern of intake associated with increased gut sulfur-metabolizing bacteria and incidence of distal colorectal cancer (CRC). We assessed whether this risk differed by CRC molecular subtypes or presence of intratumoral microbes involved in CRC pathogenesis (Fusobacterium nucleatum and Bifidobacterium spp.).
METHODS: We performed Cox proportional hazards modeling to examine the association between the sulfur microbial diet and incidence of overall and distal CRC by molecular and microbial subtype in the Health Professionals Follow-Up Study (1986-2012).
RESULTS: We documented 1,264 incident CRC cases among 48,246 men, approximately 40% of whom had available tissue data. After accounting for multiple hypothesis testing, the relationship between the sulfur microbial diet and CRC incidence did not differ by subtype. However, there was a suggestion of an association by prostaglandin synthase 2 (PTGS2) status with a multivariable adjusted hazard ratio for highest vs lowest tertile of sulfur microbial diet scores of 1.31 (95% confidence interval: 0.99-1.74, Ptrend = 0.07, Pheterogeneity = 0.04) for PTGS2-high CRC. The association of the sulfur microbial diet with distal CRC seemed to differ by the presence of intratumoral Bifidobacterium spp. with an adjusted hazard ratio for highest vs lowest tertile of sulfur microbial diet scores of 1.65 (95% confidence interval: 1.14-2.39, Ptrend = 0.01, Pheterogeneity = 0.03) for Bifidobacterium-negative distal CRC. We observed no apparent heterogeneity by other tested molecular markers.
DISCUSSION: Greater long-term adherence to the sulfur microbial diet could be associated with PTGS2-high and Bifidobacterium-negative distal CRC in men. Additional studies are needed to further characterize the role of gut microbial sulfur metabolism and CRC
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