1,531 research outputs found
Regime shifts and heterogeneous trends in malaria time series from Western Kenya Highlands
Large malaria epidemics in the East African highlands during the mid and late 1990s kindled a stream of research on the role that global warming might have on malaria transmission. Most of the inferences using temporal information have been derived from a malaria incidence time series from Kericho. Here, we report a detailed analysis of 5 monthly time series, between 15 and 41 years long, from West Kenya encompassing an altitudinal gradient along Lake Victoria basin. We found decreasing, but heterogeneous, malaria trends since the late 1980s at low altitudes (<1600 m), and the early 2000s at high altitudes (>1600 m). Regime shifts were present in 3 of the series and were synchronous in the 2 time series from high altitudes. At low altitude, regime shifts were associated with a shift from increasing to decreasing malaria transmission, as well as a decrease in variability. At higher altitudes, regime shifts reflected an increase in malaria transmission variability. The heterogeneity in malaria trends probably reflects the multitude of factors that can drive malaria transmission and highlights the need for both spatially and temporally fine-grained data to make sound inferences about the impacts of climate change and control/elimination interventions on malaria transmission
A Case of Anti-BP180-type Mucous Membrane Pemphigoid with IgG and IgA Autoantibodies Showing Distinct Reactivities
Mucous membrane pemphigoid (MMP) is an autoimmune blistering disease characterized by erosive
mucosal lesions mainly on the oral and ocular mucosae (1). We report a case of oral and ocular anti-BP180-
type MMP with variable IgG and IgA reactivities and
underlying dementia.
An 84-year-old Japanese man presented with a
4-year history of erosions in the oral cavity and on the
conjunctivae, with progressive vision impairment.
The medical history included benign prostatic hyperplasia, cataract, sinusitis, and dementia. Physical examination revealed erosions and white atrophic scars
along the gingival mucosa and on the hard palate
(Figure 1, a, b). Conjunctival inflammation and corneal scarring were also observed only on the left eye
(Figure 1, c, d). No lesions were observed on the skin
or on any other mucosae.
A skin biopsy from the patient’s oral mucosa
showed lymphocytic infiltration in the superficial
dermis without apparent subepithelial blister. Direct
immunofluorescence showed linear depositions of
IgG, IgA, and C3 at the epithelial basement membrane zone (Figure 1, e-g)
The asymptotic behavior of least pseudo-Anosov dilatations
For a surface with marked points and fixed genus , we prove
that the logarithm of the minimal dilatation of a pseudo-Anosov homeomorphism
of is on the order of . This is in contrast with the cases of
genus zero or one where the order is .Comment: 21 pages, 12 figure
Numerical simulation of interaction between two Savonius turbines aimed at practical application of ocean current power generation
One of the vertical axis wind turbines that utilize drag force is the Savonius wind turbine. Savonius wind turbines are characterized by low speed rotation and high torque, so they are rarely used for wind power generation but have possibility to apply to ocean current power generation, which has been attracting attention recently. In this report, we actually performed a numerical simulation of the flow using suitable grid, focusing mainly on the case where two wind turbines are rotating in reverse at a constant speed, and investigated the state of the flow field. Two-dimensional incompressible Navier-Stokes equations are adopted as the basic equation and solved numerically using the finite difference method. In addition, in order to enable calculation even in a high Reynolds number flow, the nonlinear term of the equations are approximated by using the third-order accuracy upstream difference method. The simulation is performed under the condition that the flow corresponds to three types of angles of 90 degrees, 45 degrees, and 0 degrees with respect to the line connecting the centers of the two wind turbines. The flow field differs greatly depending on each angle, and the interaction between the two wind turbines has been clarified
Small dilatation pseudo-Anosov mapping classes coming from the simplest hyperbolic braid
In this paper we study the minimum dilatation pseudo-Anosov mapping classes
coming from fibrations over the circle of a single 3-manifold, the mapping
torus for the "simplest pseudo-Anosov braid". The dilatations that arise
include the minimum dilatations for orientable mapping classes for genus
g=2,3,4,5,8 as well as Lanneau and Thiffeault's conjectural minima for
orientable mapping classes, when g = 2,4 (mod 6). Our examples also show that
the minimum dilatation for orientable mapping classes is strictly greater than
the minimum dilatation for non-orientable ones when g = 4,6,8.Comment: 16 pages. 5 figures. Contains minor corrections to previous
submission
Bidirectional Relationship Between Sleep Disturbances and Parkinson's Disease
Parkinson's disease (PD) is the second most common neurodegenerative disease after Alzheimer's disease (AD). Both diseases share common clinical and pathological features: the gradual progression of neurological and psychiatric symptoms caused by neuronal dysfunction and neuronal cell death due to the accumulation of misfolded and neurotoxic proteins. Furthermore, both of them are multifactorial diseases in which both genetic and non-genetic factors contribute to the disease course. Non-genetic factors are of particular interest for the development of preventive and therapeutic approaches for these diseases because they are modifiable; of these, sleep is a particularly intriguing factor. Sleep disturbances are highly prevalent among both patients with AD and PD. To date, research has suggested that sleep disturbances are a consequence as well as a risk factor for the onset and progression of AD, which implies a bidirectional relationship between sleep and AD. Whether such a relationship exists in PD is less certain, albeit highly plausible given the shared pathomechanisms. This review examines the current evidence for the bidirectional relationship between sleep and PD. It includes research in both humans and animal models, followed by a discussion of the current understanding of the mechanisms underlying this relationship. Finally, potential avenues of research toward achieving disease modification to treat or prevent PD are proposed. Although further efforts are crucial for preventing the onset and slowing the progress of PD, it is evident that sleep is a valuable candidate target for future interventions to improve the outcomes of PD patients
Synthesis and properties of 4′-ThioDNA: unexpected RNA-like behavior of 4′-ThioDNA
The synthesis and properties of fully modified 4′-thioDNAs, oligonucleotides consisting of 2′-deoxy-4′-thionucleosides, were examined. In addition to the known literature properties (preferable hybridization with RNA and resistance to endonuclease hydrolysis), we also observed higher resistance of 4′-thioDNA to 3′-exonuclease cleavage. Furthermore, we found that fully modified 4′-thioDNAs behaved like RNA molecules in their hybridization properties and structural aspect, at least in the case of the 4′-thioDNA duplex. This observation was confirmed by experiments using groove binders, in which a 4′-thioDNA duplex interacts with an RNA major groove binder, lividomycin A, but not with DNA groove binders, to give an increase in its thermal stability. Since a 4′-thioDNA duplex competitively inhibited the hydrolysis of an RNA duplex by RNase V(1), it was not only the physical properties but also this biological data suggested that a 4′-thioDNA duplex has an RNA-like structure
Magnetic properties of the S = 1 Kitaev model with anisotropic interactions
We investigate magnetic properties in the Kitaev model in the
anisotropic limit. Performing the fourth-order perturbation expansion with
respect to the -bonds, -bonds, and magnetic field, we derive the
effective Hamiltonian, where the low-energy physics should be described by the
free spins with an effective magnetic field. Making use of the exact
diagonalization method for small clusters, we discuss ground-state properties
in the system complementary.Comment: 6 pages, 4 figure
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