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Background: This work investigated the differences in the biomechanical properties of open reduction and internal fixation (ORIF) and percutaneous minimally invasive fixation (PMIF) for the fixation of calcaneal fractures (Sanders type II and III calcaneal fractures as examples) through finite element analysis. Methods: Based on CT images of the human foot and ankle, according to the principle of three-point fixation, namely the sustentaculum tali, the anterior process and the calcaneal tuberosity were fixed. Three-dimensional finite element models of Sanders type II and III calcaneal fractures fixed by ORIF and PMIF were established. The proximal surfaces of the tibia, fibula and soft tissue were constrained, and ground reaction force and Achilles tendon force loads were added to simulate balanced standing. Results: The maximum stress was 80.54, 211.59 and 113.88 MPa for the calcaneus, screws and plates in the ORIF group and 70.02 and 209.46 MPa for the calcaneus and screws in the PMIF group, respectively; the maximum displacement was 0.26, 0.21 and 0.12 mm for the calcaneus, screws and plates in the ORIF group and 0.20 and 0.14 mm for the calcaneus and screws in the PMIF group, respectively. The values obtained from the simulation were within the permissible stress and elastic deformation range of the materials used in the model, and there was no significant stress concentration. The maximum stress and displacement of the calcaneus and implants were slightly lower in the PMIF group than in the ORIF group when fixing Sanders type II and III calcaneal fractures. Conclusions: This study may provide a reference for optimising the design of implants, the development of individualised preoperative plans and the choice of clinical surgical approach. [ABSTRACT FROM AUTHOR]

Background: This work investigated the differences in the biomechanical properties of open reduction and internal fixation (ORIF) and percutaneous minimally invasive fixation (PMIF) for the fixation of calcaneal fractures (Sanders type II and III calcaneal fractures as examples) through finite element analysis. Methods: Based on CT images of the human foot and ankle, according to the principle of three-point fixation, namely the sustentaculum tali, the anterior process and the calcaneal tuberosity were fixed. Three-dimensional finite element models of Sanders type II and III calcaneal fractures fixed by ORIF and PMIF were established. The proximal surfaces of the tibia, fibula and soft tissue were constrained, and ground reaction force and Achilles tendon force loads were added to simulate balanced standing. Results: The maximum stress was 80.54, 211.59 and 113.88 MPa for the calcaneus, screws and plates in the ORIF group and 70.02 and 209.46 MPa for the calcaneus and screws in the PMIF group, respectively; the maximum displacement was 0.26, 0.21 and 0.12 mm for the calcaneus, screws and plates in the ORIF group and 0.20 and 0.14 mm for the calcaneus and screws in the PMIF group, respectively. The values obtained from the simulation were within the permissible stress and elastic deformation range of the materials used in the model, and there was no significant stress concentration. The maximum stress and displacement of the calcaneus and implants were slightly lower in the PMIF group than in the ORIF group when fixing Sanders type II and III calcaneal fractures. Conclusions: This study may provide a reference for optimising the design of implants, the development of individualised preoperative plans and the choice of clinical surgical approach. [ABSTRACT FROM AUTHOR]

Elucidating single‐atom effects on the fundamental properties of nanoparticles is challenging because single‐atom modifications are typically accompanied by appreciable changes to the overall particle's structure. Herein, we report the synthesis of a [Cu58H20PET36(PPh3)4]2+ (Cu58; PET: phenylethanethiolate; PPh3: triphenylphosphine) nanocluster—an atomically precise nanoparticle—that can be transformed into the surface‐defective analog [Cu57H20PET36(PPh3)4]+ (Cu57). Both nanoclusters are virtually identical, with five concentric metal shells, save for one missing surface copper atom in Cu57. Remarkably, the loss of this single surface atom drastically alters the reactivity of the nanocluster. In contrast to Cu58, Cu57 shows promising activity for click chemistry, particularly photoinduced [3+2] azide‐alkyne cycloaddition (AAC), which is attributed to the active catalytic site in Cu57 after the removal of one surface copper atom. Our study not only presents a unique system for uncovering the effect of a single‐surface atom modification on nanoparticle properties but also showcases single‐atom surface modification as a powerful means for designing nanoparticle catalysts. [ABSTRACT FROM AUTHOR]

Elucidating single‐atom effects on the fundamental properties of nanoparticles is challenging because single‐atom modifications are typically accompanied by appreciable changes to the overall particle's structure. Herein, we report the synthesis of a [Cu58H20PET36(PPh3)4]2+ (Cu58; PET: phenylethanethiolate; PPh3: triphenylphosphine) nanocluster—an atomically precise nanoparticle—that can be transformed into the surface‐defective analog [Cu57H20PET36(PPh3)4]+ (Cu57). Both nanoclusters are virtually identical, with five concentric metal shells, save for one missing surface copper atom in Cu57. Remarkably, the loss of this single surface atom drastically alters the reactivity of the nanocluster. In contrast to Cu58, Cu57 shows promising activity for click chemistry, particularly photoinduced [3+2] azide‐alkyne cycloaddition (AAC), which is attributed to the active catalytic site in Cu57 after the removal of one surface copper atom. Our study not only presents a unique system for uncovering the effect of a single‐surface atom modification on nanoparticle properties but also showcases single‐atom surface modification as a powerful means for designing nanoparticle catalysts. [ABSTRACT FROM AUTHOR]

A broadband ultra‐thin metamaterial absorber (MA) with a multilayer structure is proposed. The G‐type metal layer (GTML) and the square ring metal layer (SRML) are attached to the upper and lower surfaces of the dielectric substrate. Its bandwidth is determined by the high frequency resonant point f퐻0 and low frequency resonant point f퐿0 generated by GTML and SRML. The MA with unit size of 19 mm × 19 mm × 8.6 mm was simulated, manufactured and measured. The results show that the bandwidth of the structure can cover 2.89–8.06 GHz, and the relative bandwidth is 94.43%. Compared with other structures, the total thickness of the element is only 0.083λL, where λ퐿 is the wavelength at 2.89 GHz. [ABSTRACT FROM AUTHOR]

The method of using millimeter-wave radar sensors to detect human vital signs, namely respiration and heart rate, has received widespread attention in non-contact monitoring. These sensors are compact, lightweight, and able to sense and detect various scenarios. However, it still faces serious problems of noisy interference in hardware, which leads to a low signal-to-noise ratio (SNR). We used a frequency-modulated continuous wave (FMCW) radar sensor operating at 77 GHz in an office environment to extract the respiration and heart rate of a person accustomed to sitting in a chair. Indeed, the proposed signal processing includes novel impulse denoising operations and the spectral estimation decision method, which are unique in terms of noise reduction and accuracy improvement. In addition, the proposed method provides high-quality, repeatable respiration and heart rates with relative errors of 1.33% and 1.96% on average compared with the reference values measured by a reliable smart bracelet. [ABSTRACT FROM AUTHOR]

• Women who have a lower level of education, a lower level of income, and a higher body mass index (BMI) should prioritize their ovarian function. • A decline in ovarian function has a detrimental effect on the occurrence of depression, quality of life, blood pressure, and blood lipids. • A study to investigate the dynamic influence of ovarian aging on women's lives is needed. • The protocol of a prospective study to examine the ovarian aging process and its relationship with health status and quality of life is presented. Ovarian aging is a continuous process comprising a gradual decrease in both the quantity and the quality of the oocytes. A decline in ovarian function leads to chronic disease and physiological problems. The aim of this study is to establish a cohort for the purpose of examining the ovarian aging process and its relationship with health status and quality of life in women across all age groups. This protocol outlines a community-based, prospective long-term observational study involving 1676 women recruited from Caofeidian District in Tangshan City, Hebei Province, China. Data are gathered by the administration of questionnaires, doing physical examinations, performing blood biochemistry tests, and measuring levels of female hormones. The primary outcomes will be the occurrence of cardiovascular disease, osteoporosis, hypertension, diabetes, hyperlipidemia, and other chronic diseases, assessed according to established diagnostic criteria for each disease. The secondary outcome will be the decline in quality of life during the follow-up period, assessed by the modified Kupperman Index. The study comprises a baseline cross-sectional assessment and a follow-up evaluation. The participants will undergo face-to-face interviews as part of their regular medical examinations until 2026 or until the occurrence of outcome events. The results of the prospective study will indicate the association between ovarian aging and the prevalence of chronic diseases as well as diminished quality of life among women across different age categories. [ABSTRACT FROM AUTHOR]

In this paper, an ultra‐wideband multiple‐input multiple‐output antenna with dual band‐notched characteristics is proposed. The radiating element is an octagonal structure using a tapered microstrip line to feed. A multimode resonator is introduced on one side of the microstrip feed line to achieve dual band‐notched characteristics, which eliminates the interference of wireless local area network band and X satellite communication frequency band. By using a diamond‐shaped defect ground structure and extending a parasitic branch at the centre axis of the ground, the mutual coupling of the antenna is reduced to −20 dB. The proposed antenna has a compact size of 30 × 35 × 0.8 mm3. The measured results are in good agreement with the simulation results. The proposed antenna covers 3.1–10.6 GHz with dual notched‐band characteristics and the mutual coupling below −20 dB. The antenna has a good diversity performance as the envelope correlation coefficient <0.03. The antenna is suitable for ultra‐wideband communications. [ABSTRACT FROM AUTHOR]

Fluorescent organic dots (O-dots) recently have emerged as a new class of promising contrast reagents for two-photon fluorescence (TPF) imaging. However, most of these developed two-photon absorption (TPA) O-dots have no tumor-targeting group, which hampers their wide application for targeted tumor imaging. Herein, we fabricated Sgc8c aptamer-mediated TPA O-dots as a proof-of-concept of the sensing platform for targeted imaging in live cells or deep tissues. The O-dots composed of trans -4-[p-(N, N-diethylamino)styryl]-4'-(dimethyl amino) stilbene (DEAS) emerged as TPA organic emissive cores and encapsulation by using poly (methyl methacrylate-co-methacrylic acid) (PMMA-co-MAA) as polymeric encapsulating matrix to form DEAS/PMMA-co-MAA O-dots via a co-precipitation strategy. The obtained O-dots enabled an extremely high TPA absorption cross-section, bright two-photon fluorescence (excitation at 720 nm; emission at 412 nm and 434 nm), excellent cell-permeability and high penetration depth. Sgc8c aptamer, as a protein tyrosine kinase-7 (PTK7) receptor-targetable ligand, was further anchored on the surface of O-dots to obtain DEAS/PMMA-co-MAA@Sgc8c nanoprobes by 1-ethyl-3-(3-dimethylaminopropyl) carbodiimide hydrochloride (EDC)-mediated coupling reaction. Guided by Sgc8c aptamer, DEAS/PMMA-co-MAA@Sgc8c nanoprobes could be rapidly internalized into target acute lymphoblastic leukemia cells (CEM) cells with high specificity and great efficiency. It was also performed that two-photon images of TPA nanoprobes exhibited high two-photon brightness not only in target CEM cells, but also in mouse liver tissue slices even a depth of up to 210 μm. In our perception, it is highly promising that this nanoprobe provides a valuable tool for in vivo targeted imaging. Image 1 • A versatile and scalable strategy to aptamer-modified two-photon DEAS/PMMA-co-MAA O-dots for targeted imaging was proposed. • The DEAS/PMMA-co-MAA O-dots enabled higher two-photon brightness (45-fold enhancement). • Sgc8c acts as a tumor-specific ligand is introduced to TP nanoprobes, applying for precision targeting and imaging in cells. • This novel targeted nanoprobes was capable of two-photon imaging up to 210 μm in liver tissue slices. [ABSTRACT FROM AUTHOR]

Silver chalcogenolate clusters (SCCs) and silver cluster‐assembled materials (SCAMs) are an important category of novel luminescent materials, the emission of which can be modulated by variation of the cluster nodes and linker species. Here, the successfully synthesis of two isostructural 2D SCAMs is reported: Ag12bpa and Ag12bpe are formed by using two linkers with different conformational freedom (bpa=1,2‐bis(4‐pyridyl)ethane, bpe=1,2‐bis(4‐pyridyl)ethylene), with dodenuclear silver chalcogenolate clusters as secondary building units (SBUs). Interestingly, nonluminescent Ag12bpa at room temperature could quickly transform into 1D Ag10bpa, with concomitant dissociation of two silver atoms and the remaining ten silver atoms rearranging in the cluster, thus exhibiting an intense yellow phosphorescence after being triggered by acetonitrile (CH3CN). Similarly, stimulating Ag12bpe with CH3CN, by contrast, gave another 2D structure Ag12bpe‐1b with the distorted SBUs and different topology structure, and both of them are merely red‐emissive at low temperature. To note, after exchanging ligands, room‐temperature nonluminescent 2D Ag12bpe‐1b can be transformed into intensely luminescent 1D Ag10bpa. This linker‐flexibility‐dependent structural transformation and cluster‐based SBU controlled luminescence remains scarce. Our work provides new insights into structure–luminescence relationship in clustered metal–organic frameworks and intelligent stimulus‐responsive luminescent materials. What a SCAM! Isostructural silver cluster‐assembled materials (SCAMs) Ag12bpa and Ag12bpe (bpa=1,2‐bis(4‐pyridyl)ethane, bpe=1,2‐bis(4‐pyridyl)ethylene) were synthesized by using bidentate pyridine to give identical length yet different flexibility. Ag12bpa and Ag12bpe differently respond to acetonitrile: 2D Ag12bpa, which is only red‐emissive at low temperature transforms into yellow‐emissive 1D Ag10bpa at room temperature (see figure). [ABSTRACT FROM AUTHOR]

The physiologic process of postnatal ductus arteriosus (DA) closure consists of vasoconstriction followed by vascular remodeling. We have recently reported that B-type natriuretic peptide (BNP), a potent vasodilator, also has anti-remodeling effects in pulmonary vasculature. However, its effects on DA have not been elucidated. We investigated whether BNP can prevent DA closure, and if so, the underlying mechanisms. Using in vivo studies, we examined effects of BNP (10 mg/kg, ip at birth) on DA closure in neonatal rats within 4 h after birth. We found that in control rats, the DA spontaneously closed at 4 h with a decreased DA diameter, enhanced intimal thickening, and luminal occlusion. BNP prevented DA closure at 4 h with a preserved DA diameter, attenuated intimal thickening, and preserved luminal patency. Ex vivo, BNP attenuated oxygen-induced vasoconstriction of isolated DA rings of newborn rats. These vasodilating effects were blunted by Rp-8-Br-PET-cGMPS, a cGMP inhibitor. In vitro, BNP inhibited angiotensin II (Ang II)-induced proliferation and migration of DA smooth muscle cells (DASMCs). BNP inhibited Ang II-induced mitochondrial reactive oxygen species (ROS) production and calcium overload in DASMCs. Finally, BNP inhibited Ang II-induced ERK1/2 activation. These in vitro effects were antagonized by Rp-8-Br-PET-cGMPS. In conclusion, BNP prevents postnatal DA closure by both vasodilation and anti-remodeling through the cGMP pathway. The mechanisms underlying anti-remodeling effects include anti-poliferation and anti-migration, with attenuation of mitochondrial ROS production and intracellular calcium and ERK1/2 signaling. Therefore, the BNP/cGMP pathway can be a promising therapeutic target for clinical management of DA patency. [ABSTRACT FROM AUTHOR]

In this paper, a simple broadband multipolarized traveling-wave series-fed antenna array is proposed. The radiation unit cells are multiple squares. The square unit cell will change between circular polarized (CP) and linear polarized (LP) through a reasonable feeding mode. By adjusting the equivalent length of the unit cell, the Q value of the antenna can be reduced, resulting in the increase of the bandwidth of the array. The array consists of seven-unit cells and dual-port feeding. The unit cells which are connected by a microstrip line are arranged in a circular array. A reasonable layout of unit cells can achieve good port isolation of the array. The polarization performance of the array antenna is the same as that of the unit cell. The antenna is fabricated and measured. The measured results are consistent with the simulated results. [ABSTRACT FROM AUTHOR]

Abstract: Silver chalcogenolate cluster assembled materials (SCAMs) are a category of promising light‐emitting materials the luminescence of which can be modulated by variation of their building blocks (cluster nodes and organic linkers). The transformation of a singly emissive [Ag12(SBut)8(CF3COO)4(bpy)4]n (Ag12bpy, bpy=4,4′‐bipyridine) into a dual‐emissive [(Ag12(SBut)6(CF3COO)6(bpy)3)]n (Ag12bpy‐2) via cluster‐node isomerization, the critical importance of which was highlighted in dictating the photoluminescence properties of SCAMs. Moreover, the newly obtained Ag12bpy‐2 served to construct visual thermochromic Ag12bpy‐2/NH2 by a mixed‐linker synthesis, together with dichromatic core–shell Ag12bpy‐2@Ag12bpy‐NH2‐2 via solvent‐assisted linker exchange. This work provides insight into the significance of metal arrangement on physical properties of nanoclusters. [ABSTRACT FROM AUTHOR]

Abstract: Silver chalcogenolate cluster assembled materials (SCAMs) are a category of promising light‐emitting materials the luminescence of which can be modulated by variation of their building blocks (cluster nodes and organic linkers). The transformation of a singly emissive [Ag12(SBut)8(CF3COO)4(bpy)4]n (Ag12bpy, bpy=4,4′‐bipyridine) into a dual‐emissive [(Ag12(SBut)6(CF3COO)6(bpy)3)]n (Ag12bpy‐2) via cluster‐node isomerization, the critical importance of which was highlighted in dictating the photoluminescence properties of SCAMs. Moreover, the newly obtained Ag12bpy‐2 served to construct visual thermochromic Ag12bpy‐2/NH2 by a mixed‐linker synthesis, together with dichromatic core–shell Ag12bpy‐2@Ag12bpy‐NH2‐2 via solvent‐assisted linker exchange. This work provides insight into the significance of metal arrangement on physical properties of nanoclusters. [ABSTRACT FROM AUTHOR]

Background: Pelvic inflammatory disease (PID) is a widespread female public problem worldwide. And it could lead to infertility, preterm labor, chronic pelvic pain, and ectopic pregnancy (EP) among reproductive-aged women. This study aimed to assess the global burden and trends as well as the chaning correlation between PID and EP in reproductive-aged women from 1990 to 2019. Methods: The data of PID and EP among reproductive-aged women (15 to 49 years old) were extracted from the Global Burden of Disease study 2019. The disease burden was assessed by calculating the case numbers and age-standardized rates (ASR). The changing trends and correlation were evaluated by calculating the estimated annual percentage changes (EAPC) and Pearson's correlation coefficient. Results: In 2019, the ASR of PID prevalence was 53.19 per 100,000 population with a decreasing trend from 1990 (EAPC: − 0.50), while the ASR of EP incidence was 342.44 per 100,000 population with a decreasing trend from 1990 (EAPC: − 1.15). Globally, PID and EP burdens changed with a strong positive correlation (Cor = 0.89) globally from 1990 to 2019. In 2019, Western Sub-Saharan Africa, Australasia, and Central Sub-Saharan Africa had the highest ASR of PID prevalence, and Oceania, Eastern Europe, and Southern Latin America had the highest ASR of EP incidence. Only Western Europe saw significant increasing PID trends, while Eastern Europe and Western Europe saw increasing EP trends. The highest correlations between PID and EP burden were observed in Burkina Faso, Laos, and Bhutan. General negative correlations between the socio-demographic index and the ASR of PID prevalence and the ASR of EP incidence were observed at the national levels. Conclusion: PID and EP continue to be public health burdens with a strong correlation despite slightly decreasing trends detected in ASRs globally. Effective interventions and strategies should be established according to the local situation by policymakers. [ABSTRACT FROM AUTHOR]

This article presents a novel design of a switchable dual‐band frequency‐selective rasorber/absorber, which is a double‐layered structure. At the top layer, two electric‐field‐coupled resonators with different size are utilized to achieve two transmission bands. At the bottom, to achieve low insertion loss, the frequency‐selective surface based on slots with different lengths resonates at the same frequency as the top layer. By controlling the bias voltage of PIN diodes, the structure can be switched between dual‐band rasorber/absorber mode. The operating principle is analyzed by an equivalent circuit model. When the diodes are in the OFF state, it shows two transmission bands at 2.86 GHz with 0.47 dB insertion loss and 3.61 GHz with 1.04 dB insertion loss. When the diodes are in the ON state, it exhibits a wide fractional absorption bandwidth of 90.1%. Meanwhile, the proposed dual‐band switchable structure is fabricated and measured. There is a good agreement between simulation and measurement. [ABSTRACT FROM AUTHOR]

High cogging torque is a common drawback of the interior permanent magnet machine. In this paper, a novel technique is adopted to reduce cogging torque and torque ripple by using an asymmetrical V-type rotor configuration. First, the analysis modes are presented, and the proposed rotor is optimized by the hybrid design of experiment. A satisfactory set of parameters is determined. Next, the cogging torque and the torque ripple of the proposed model are compared with those of the basic model. The results demonstrate that the cogging torque and the torque ripple are reduced significantly by the adoption of the proposed rotor. Then, the performance of the proposed model rotating clockwise is compared that of the proposed model rotating counterclockwise to evaluate the effectiveness of the proposed rotor. Finally, the validity of the proposed method is confirmed by experiment. [ABSTRACT FROM PUBLISHER]

A growing number of molecular epidemiological studies have been conducted to evaluate the association between human papillomavirus (HPV) infection and the malignancy of sinonasal inverted papilloma (SNIP). However, the results remain inconclusive. Here, a meta -analysis was conducted to quantitatively assess this association. Case-control studies investigating SNIP tissues for presence of HPV DNA were identified. The odds ratios (ORs) and 95% confidence intervals (CIs) were calculated by the Mantel-Haenszel method. An assessment of publication bias and sensitivity analysis were also performed. We calculated a pooled OR of 2.16 (95% CI = 1.46–3.21, P < 0.001) without statistically significant heterogeneity or publication bias. Stratification by HPV type showed a stronger association for patients with high-risk HPV (hrHPV) types, HPV-16, HPV-18, and HPV-16/18 infection (OR = 8.8 [95% CI: 4.73–16.38], 8.04 [95% CI: 3.34–19.39], 18.57 [95% CI: 4.56–75.70], and 26.24 [4.35–158.47], respectively). When only using PCR studies, pooled ORs for patients with hrHPV, HPV-16, and HPV18 infection still reached statistical significance. However, Egger’s test reflected significant publication bias in the HPV-16 sub-analysis (P = 0.06), and the adjusted OR was no longer statistically significant (OR = 1.65, 95%CI: 0.58–4.63). These results suggest that HPV infection, especially hrHPV (HPV-18), is significantly associated with malignant SNIP. [ABSTRACT FROM AUTHOR]

Oncostatin M (OSM) contributes to cartilage degeneration in osteoarthritis (OA) and was demonstrated to be expressed in OA osteoblasts. Endothelin-1 (ET-1) is implicated in the degradation of OA articular cartilage, and osteoblast proliferation and bone development. In the present study, the effects of ET-1 on OSM expression in human OA osteoblasts were investigated, to the best of our knowledge, for the first time. Primary human OA osteoblasts were treated with ET-1 (1, 5, 10, 20 and 30 nM) for 0.5, 1, 2, 3 and 4 h with or without the selective ETA receptor (ETAR) antagonist, BQ123, ETB receptor antagonist, BQ788 or the phosphatidylinositol 3-kinase (PI3K) inhibitor, BKM120. ET-1 treatment induced OSM mRNA expression, and the intracellular and secreted protein levels of OA osteoblasts in a dose-dependent manner. This effect was suppressed by BQ123 and BKM120, but not BQ788 administration. In combination with electrophoretic mobility shift assays, deletional and mutational analyses on the activity of a human OSM promoter/luciferase reporter demonstrated that ET-1 induced OSM expression in OA osteoblasts by trans-activating the OSM gene promoter through specific binding of Ets-1 to an Ets-1 binding site in the OSM promoter in an ETAR- and PI3K-dependent manner. Furthermore, ET-1 treatment increased the expression of Ets-1 in a dose-dependent manner, however the knockdown of Ets-1 suppressed the ET1-induced expression of OSM in OA osteoblasts. In conclusion, the present study demonstrated that ET-1 induces the expression of OSM in OA osteoblasts by trans-activating the OSM gene promoter primarily through increasing the expression level of Ets-1 in an ETAR- and PI3K-dependent manner. The current study suggested novel insights into the mechanistic role of ET-1 in the pathophysiology of OA. [ABSTRACT FROM AUTHOR]

Taking the standard wheel model as an example, the radiation noise of a single wheel under excitation force which is computed by multi-body dynamics model is computed by acoustic boundary element method (BEM). Then, the damped wheel is proposed, and the sound radiation characteristics of both wheels are analyzed and compared. The results show that sound field of a single wheel presents an obvious directivity with petaloid change and continuous decrease, and the wheel tread and web contribute the most rolling noise. Compared with the standard wheel, the acoustic radiation power of the damped wheel decreased significantly, especially at the peak frequency. After that, the radiation noise generated by the wheel in the train is researched. The results show that the radiation noise generated by the wheel in the train is a complex sound field after the superposition and interference of multiple wheel noises, which are mainly in the bogies at both ends and its vicinity region. Meanwhile, the basic directivity characteristics of the petaloid change and continuous reduction are remained. The radiation noise which is generated by the wheel in the train has obvious peak characteristic, whose corresponding peak noises are below 110 dB. The radiation noise of the damped wheel is significantly smaller than that of the standard wheel at most frequency bands, and the total SPL at the observation point has decreased by 14.5 dB with obvious noise reduction effect. In order to further research the radiation noise of the damping wheel, influence factors on the noise reduction are analyzed. Finally, these parameters such as thickness and material should be considered comprehensively during designing the damping wheel, in order to find the optimal combination of all parameters. [ABSTRACT FROM AUTHOR]

The purpose of this paper is to present an asymmetrical V-shape rotor configuration of an interior permanent magnet (IPM) machine for improving the torque characteristics, i.e., reducing cogging torque and torque ripple. Using this rotor configuration, the great reduction of the cogging torque and the torque ripple can be achieved. To acquire more desired torque characteristics, an optimization design is implemented using hybrid genetic algorithm-Taguchi (HGAT). Time-stepping finite-element analysis is adopted to calculate the torque characteristics for comparison and analyses. The best set of design parameters is found out; and the IPM model optimized using the HGAT shows even better torque characteristics. An IPM machine prototype having HGAT-design parameters was manufactured for test, and the effectiveness of the proposed rotor is verified by comparison between the simulation and the experiment results. [ABSTRACT FROM AUTHOR]

A novel discrete open high-nuclearity nest-like silver thiolate cluster complex, [Ag33S3(S tBu)16(CF3COO)9(NO3)(CH3CN)2](NO3) ( 1), has been isolated with nitrate and S2− anions acting as structure-directing templates. Its similar nest-like structure has been assembled into an extended layer [Ag31S3(S tBu)16(NO3)9] n ( 2) by adjustment of auxiliary ligand. More interestingly, both complexes exhibit temperature-dependent luminescence of high sensitivity with a large fluorescence enhancement (12-fold for 1, 21-fold for 2), which can be easily recognized by the naked-eye (dramatic red-shift Δ=104 nm for 1, larger Δ=113 nm for 2 at 77 K compared to those at 298 K). The correlation between luminescent thermochromism and temperature-dependent variation of the coordination modes of template NO3− anion, Ag⋅⋅⋅S and Ag⋅⋅⋅Ag distances are also elucidated through variable-temperature single-crystal X-ray crystal structure (VT-SCXRD) analyses. [ABSTRACT FROM AUTHOR]

The aim of this study is to explore the effect and mechanism of 3,6'-disinapoylsucrose (DISS) on an Alzheimer's disease (AD) mice model induced by APPswe695 lentivirus (LV) and intraperitoneal injection of lipopolysaccharide (LPS). The results show that DISS improves cognitive ability, decreases the levels of IL-2, IL-6, IL-1β, and TNF-α, reduces the expression of NF-κB p65, and alleviates Aβ deposition and nerve cell damage. DISS can regulate tyrosine kinase B (TrkB)/brain-derived neurotrophic factor (BDNF) signaling in the hippocampus. In summary, DISS can significantly alleviate neuroinflammation, spatial learning and memory disorders in AD model mice. [ABSTRACT FROM AUTHOR]

A variety of non-noble electrocatalysts (Fe(III)Nx/C and Fe(II)N6/C) have been fabricated by pyrolyzing nitrogen-rich compounds (ethylenediamine, tetraethylenepetamine and pentaethylenehexamine) and iron precursors (iron(III) chloride and iron(II) ammonium sulphate) on carbon blacks (Vulcan XC-72) in a nitrogen atmosphere. The catalytic performance (activity and durability) toward oxygen reduction reaction (ORR) is comparatively examined by rotating disk electrode and chronoamperometric techniques. The results show that nitrogen precursors play a crucial role on the chemical microstructure and performance of electrocatalysts. The influence of various nitrogen and iron precursors on the properties of electrocatalysts has been analyzed by X-ray based spectroscopies including X-ray diffraction (XRD), X-ray photoelectron spectroscopy (XPS) and X-ray absorption spectroscopy (XAS). Among all the Fe(III)Nx/C and Fe(II)N6/C catalysts, Fe(III)N6/C catalysts which pentaethylenehexamine and iron(III) chloride are used as starting precursors possess the superior electrocatalytic ORR activity and durability probably due to their higher surface Fe/C and N/C atomic ratios with the pyridinic-N and quaternary-N active sites for the formation of the FeN4 species, as verified by XPS and XAS analyses. [ABSTRACT FROM AUTHOR]

The reactions of flexible supramolecular synthons with a pendant ethynide arm attached to a heteroaryl skeleton and different silver(I) salts under solvent evaporation conditions yielded four silver-organic frameworks. In 1-4, the Ag7, Ag8 and Ag9 aggregates are fused together through trifluoroacetate groups and/or Ag-N coordination bonds to generate a 2D layer, and finally linked into 3D supramolecular networks by argentophilic interactions or hydrogen bonding. The diversities of the present structures also indicate that both solvent and the anionic component play vital roles in the assembly of silver(I)- ethynide complexes. In addition, their luminescence behaviors have been studied in the solid state. [ABSTRACT FROM AUTHOR]

The utilization of nanostructure graphene thin films as electron transfer layer in dye-sensitized solar cells (DSSCs) was demonstrated. The effect of a nanostructure graphene thin film in DSSC structure was examined. The nanostructure graphene thin films provides a great electron transfer channel for the photogenerated electrons from TiO2 to indium tin oxide (ITO) glass. Obvious improvements in short-circuit current density of the DSSCs were observed by using the graphene electron transport layer modified photoelectrode. The graphene electron transport layer reduces effectively the back reaction in the interface between the ITO transparent conductive film and the electrolyte in the DSSC. [ABSTRACT FROM AUTHOR]

Abstract: Three new coordination polymers, namely, [ML(H2O)] n (M=Co (1), Zn (2)) and [CuL(DMF)] n (3), have been hydrothermally synthesized through the reaction of bifunctional ligand 5-((2-methyl-1H-imidazol-1-yl)methyl)benzene-1,3-dioic acid (H2L) with divalent cobalt, zinc and copper salts, and structurally characterized by elemental analysis, IR and X-ray diffraction. Both complexes 1 and 2 are two-fold interpenetration 3D frameworks. Complex 3 exhibits (3,6)-connected framework with (4.62)2(42.610.83) topology. Furthermore, UV–vis absorption spectra and powder X-ray diffraction (PXRD) were investigated as well. [Copyright &y& Elsevier]

The pair of screw rotors is a key element of a twin-screw compressor, and rotor tooth modification has gradually received attention because it can reduce operating compressor noise. Current rotor machining references are mainly related to forming tool design or abrasion of the "horizontal" grinder, but little attention has been paid to form grinding using a "vertical" grinder and simulating the machining flexibility of each grinder axis. Therefore, this paper established a general coordinate system for the screw rotor form grinding and connected it to a vertical five-axis computerized numerical control form grinder to simulate rotor grinding and tooth modification. Further, the influence of a form grinding wheel contour designed by different declination angles of a rotor tooth profile on a grinding rotor tooth and the influence of the motion parameter of each axis on the machining precision of the rotor and the tooth shape are proposed in this paper. [ABSTRACT FROM AUTHOR]

Abstract: A new thick silver rod incorporating repeated Ag3 units sustained by 1,3,5-benzenetricarboxylic acid (1,3,5-H3BTC) and Ag⋯Ag interactions, {[Ag3(BTC)(pyz)]·(H2O)} n (1) (pyz=pyrazine), has been synthesized and structurally characterized. Compound 1 displays a three-dimensional coordination framework with infinite 1D Ag rod, and adjacent silver rods bridged by the 1,3,5-H3BTC and pyz ligand. Argentophilicity plays an important role in determining the infinite silver(I) rods. Complex 1 exhibits photoluminescence maximized at 542nm upon 363nm excitation at room temperature, which may be mainly assigned to ligand-to-metal charge transfer (LMCT) perturbed by Ag⋯Ag interactions. Temperature dependent luminescence spectra from 298 to 77K have been studied. Upon decreasing the temperature from 298 to 77K, the emission bands grow in intensity. In addition, the thermogravimetric analysis and powder X-ray diffraction (PXRD) of complex 1 have also been investigated. [Copyright &y& Elsevier]

The technology to focus hard-X-rays (photon energy larger than 1-2 keV) has made great progress in the past three years. The progress was particularly spectacular for lenses based on the Fresnel zone plate concept. The spatial resolution notably increased by a factor of three, opening up entirely new domains of application, specifically in biomedical research. As we shall see, this evolution is the result of a painstaking optimization of many different aspects rather than of a single technical breakthrough [ABSTRACT FROM AUTHOR]

Serine-rich repeat glycoproteins identified from streptococci and staphylococci are important for bacterial adhesion and biofilm formation. Two putative glycosyltransferases, Gtf1 and Gtf2, from Streptococcus parasanguinis form a two-protein enzyme complex that is required for glycosylation of a serine-rich repeat adhesin, Fap1. Gtf1 is a glycosyltransferase; however, the function of Gtf2 is unknown. Here, we demonstrate that Gtf2 enhances the enzymatic activity of Gtf1 by its chaperone-like property. Gtf2 interacted with Gtf1, mediated the subcellular localization of Gtf1, and stabilized Gtf1. Deletion of invariable amino acid residues in a conserved domain of unknown function (DUF1975) at the N terminus of Gtf2 had a greater impact on Fap1 glycosylation than deletion of the C-terminal non-DUF1975 residues. The DUF1975 deletions concurrently reduced the interaction between Gtf1 and Gtf2, altered the subcellular localization of Gtf1, and destabilized Gtf1, suggesting that DUF1975 is crucial for the chaperone activity of Gtf2. Homologous GtfA and GtfB from Streptococcus agalactiae rescued the glycosylation defect in the gtf1gtf2 mutant; like Gtf2, GtfB also possesses chaperone-like activity. Taken together, our studies suggest that Gtf2 and its homologs possess the conserved molecular chaperone activity that mediates protein glycosylation of bacterial adhesins. [ABSTRACT FROM AUTHOR]

A new family of bacterial serine-rich repeat glycoproteins can function as adhesins required for biofilm formation and pathogenesis in streptococci and staphylococci. Biogenesis of these proteins depends on a gene cluster coding for glycosyltransferases and accessory secretion proteins. Previous studies show that Fap1, a member of this family from Streptococcus parasanguinis, can be glycosylated by a protein glycosylation complex in a recombinant heterogeneous host. Here we report a tandem affinity purification (TAP) approach used to isolate and study protein complexes from native streptococci. This method demonstrated that a putative glycosyltransferase (Gtf2), which is essential for Fap1 glycosylation, readily copurified with another glycosyltransferase (Gtf1) from native S. parasanguinis. This result and the similar isolation of a homologous two-protein complex from Streptococcus pneumoniae indicate the biological relevance of the complexes to the glycosylation in streptococci. Furthermore, novel N-acetylglucosaminyltransferase activity was discovered for the complexes. Optimal activity required heterodimer formation and appears to represent a novel type of glycosylation. [ABSTRACT FROM AUTHOR]

This paper introduces a new hybrid image enhancement approach driven by both global and local processes on luminance and chrominance components of the image. This approach, based on the parameter-controlled virtual histogram distribution method, can enhance simultaneously the overall contrast and the sharpness of an image. The approach also increases the visibility of specified portions or aspects of the image whilst better maintaining image colour. The approach was compared with other well-known image enhancement techniques. The experimental results have shown the superiority of the proposed approach. [ABSTRACT FROM AUTHOR]

AbstractGlycine-proline-glutamate (GPE) is an N-terminal tripeptide endogenously cleaved from insulin-like growth factor-1 in the brain and is neuroprotective against hypoxic-ischemic brain injury and neurodegeneration. NNZ-2566 is an analog of GPE designed to have improved bioavailability. In this study, we tested NNZ-2566 in a rat model of penetrating ballistic-type brain injury (PBBI) and assessed its effects on injury-induced histopathology, behavioral deficits, and molecular and cellular events associated with inflammation and apoptosis. In the initial dose-response experiments, NNZ-2566 (0.01–3 mg/kg/h × 12 h intravenous infusion) was given at 30 min post-injury and the therapeutic time window was established by delaying treatments 2–4 h post-injury, but with the addition of a 10- or 30-mg/kg bolus dose. All animals survived 72 h. Neuroprotection was evaluated by balance beam testing and histopathology. The effects of NNZ-2566 on injury-induced changes in Bax and Bcl-2 proteins, activated microgliosis, neutrophil infiltration, and astrocyte reactivity were also examined. Behavioral results demonstrated that NNZ-2566 dose-dependently reduced foot faults by 19–66% after acute treatments, and 35–55% after delayed treatments. Although gross lesion volume was not affected, NNZ-2566 treatment significantly attenuated neutrophil infiltration and reduced the number of activated microglial cells in the peri-lesion regions of the PBBI. PBBI induced a significant upregulation in Bax expression (36%) and a concomitant downregulation in Bcl-2 expression (33%), both of which were significantly reversed by NNZ-2566. Collectively, these results demonstrated that NNZ-2566 treatment promoted functional recovery following PBBI, an effect related to the modulation of injury-induced neural inflammatory and apoptotic mechanisms. [ABSTRACT FROM AUTHOR]

The tsunami propagation and coastal run-ups generated by the 2006 Pingtung earthquake doublet is studied numerically. The numerical model -- COMCOT, which adopts a modified Leap-Frog finite difference scheme solving nonlinear Shallow Water Equations (NSWE), is employed. The assessment of the tsunami amplitude and extended effects is discussed in this paper using a set of nested bathymetric grids with a decreasing cell size focused on southern Taiwan. The three nested grids cover from the large far-field South-China Sea to the small near-shore regions. Several possible fault plane mechanisms are examined. Based on the arrival time at different tidal gauges, the suggested seafloor displacement is presented. Adopting the relocated seafloor movement with the fault parameters issued by Global CMT, the model results are favorably compared with the field tidal gauge wave form data. The result shows that the tsunami amplitude is about 35 cm and about 20-min period with the first depression at SyunGuaggZuei. A worse case scenario, Mw = 8.0, is studied. The maximum water levels can reach 4 m for Mw = 8.0 along the shoreline at HouBiHu. We also observe that owning to the source geometries and to the trapping of the tsunami energy by edge wave effect, the south-east coast of Taiwan coast is one of the most dangerous zones for the South China Sea earthquakes. [ABSTRACT FROM AUTHOR]

The title compound [systematic name: 2-(2-acrylamidoacetamido)acetic acid monohydrate], C7H10N2O4·H2O, was prepared by the nucleophilic substitution reaction of acryloyl chloride with glycylglycine. Excluding H atoms, the main chain of the molecule is nearly planar. In the crystal structure, O—H⋯O, N—H⋯O and C—H⋯O hydrogen bonds link the molecules into a three-dimensional network. [ABSTRACT FROM AUTHOR]

Abstract: In an earlier study, we demonstrated that PAN-811 (3-aminopyridine-2-carboxaldehyde thiosemicarbazone), a novel neuroprotectant, provides protection against glutamate, staurosporine, veratridine, or hypoxia/hypoglycemia toxicities in primary cortical neuronal cultures by upregulating Bcl-2 expression [R.-W. Chen, C. Yao, X.C. Lu, Z.-G. Jiang, R. Whipple, Z. Liao, H.A. Ghanbari, B. Almassian, F.C. Tortella, J.R. Dave. PAN-811 (3-aminopyridine-2-carboxaldehyde thiosemicarbazone), a novel neuroprotectant, elicits its function in primary neuronal cultures by upregulating Bcl-2 expression. Neuroscience 135 (2005) 191–201]. Both JNK (c-Jun N-terminal kinase) and p38 MAP (mitogen-activated protein) kinase activation have a direct inhibitory action on Bcl-2 by phosphorylation. In the present study, we continued to explore the mechanism of PAN-811 neuroprotection. Our results indicate that treatment of cultured cortical neurons with glutamate (100μM) induces phosphorylation of both JNK and p38 MAPK. Specifically, pretreatment of neurons with 10μM PAN-811 (an optimal neuroprotective concentration) for 1h, 4h, or 24h significantly suppresses glutamate-mediated activation of both JNK and p38 MAPK. Furthermore, the p38 MAPK-specific inhibitor SB203580 and the JNK-specific inhibitor SP600125 prevented glutamate-induced neuronal death in these primary cultures. Our results demonstrate that glutamate-induced phosphorylation of JNK and p38 MAPK is suppressed by PAN-811, which might contribute to Bcl-2 upregulation and PAN-811 neuroprotection. [Copyright &y& Elsevier]

Abstract: Cellular injury can involve the aberrant stimulation of cell cycle proteins in part through activation of phosphodiesterases (PDEs) and downstream expression of cell-cycle components such as cyclin D1. In mature non-proliferating cells activation of the cell cycle can lead to the induction of programmed cell death. In the present study, we investigated the in vitro neuroprotective efficacy and mechanism of action of vinpocetine (PDE1 inhibitor), trequinsin (PDE3 inhibitor), and rolipram (PDE4 inhibitor) in four mechanistically-distinct models of injury to primary rat cortical neurons as related to cell cycle regulation and apoptosis. Cellular injury was induced by hypoxia/hypoglycemia, veratridine (10μM), staurosporine (1μM), or glutamate (100μM), resulting in average neuronal cell death rates of 43–48% as determined by MTT assay. Treatment with each PDE inhibitor (PDEI) resulted in a similar concentration-dependent neuroprotection profile with maximal effective concentrations of 5–10μM (55–77% neuroprotection) in all four neurotoxicity models. Direct cytotoxicity due to PDE inhibition alone was not observed at concentrations below 100μM. Further studies indicated that PDEIs can suppress the excitotoxic upregulation of cyclin D1 similar to the effects of flavopiridol, a cyclin-dependent kinase inhibitor, including suppression of pro-apoptotic capase-3 activity. Overall, these data indicate that PDEIs are broad-spectrum neuroprotective agents acting through modulation of cell cycle elements and may offer a novel mode of therapy against acute injury to the brain. [Copyright &y& Elsevier]

A new adaptive backpropagation (BP) algorithm based on Lyapunov stability theory for neural networks is developed in this paper. It is shown that the candidate of a Lyapunov function V(k) of the tracking error between the output of a neural network and the desired reference signal is chosen first, and the weights of the neural network are then updated, from the output layer to the input layer, in the sense that ΔV(κ) = V(κ) — V(κ — 1) < 0. The output tracking error can then asymptotically converge to zero according to Lyapunov stability theory. Unlike gradient-based BP training algorithms, the new Lyapunov adaptive BP algorithm in this paper is not used for searching the global minimum point along the cost-function surface in the weight space, but it is aimed at constructing an energy surface with a single global minimum point through the adaptive adjustment of the weights as the time goes to infinity. Although a neural network may have bounded input disturbances, the effects of the disturbances can be eliminated, and asymptotic error convergence can be obtained. The new Lyapunov adaptive BP algorithm is then applied to the design of an adaptive filter in the simulation example to show the fast error convergence and strong robustness with respect to large bounded input disturbances. [ABSTRACT FROM AUTHOR]

A partition-based adaptive vector filter is proposed for the restoration of corrupted digital color images. The novelty of the filter lies in its unique three-stage adaptive estimation. The local image structure is first estimated by a series of center-weighted reference filters. Then the distances between the observed central pixel and estimated references are utilized to classify the local inputs into one of preset structure partition cells. Finally, a weighted filtering operation, indexed by the partition cell, is applied to the estimated references in order to restore the central pixel value. The weighted filtering operation is optimized off-line for each partition cell to achieve the best tradeoff between noise suppression and structure preservation. Recursive filtering operation and recursive weight training are also investigated to further boost the restoration performance. The proposed filter has demonstrated satisfactory results in suppressing many distinct types of noise in natural color images. Noticeable performance gains are demonstrated over other prior-art methods in terms of standard objective measurements, the visual image quality and the computational complexity. [ABSTRACT FROM AUTHOR]

The resonant flow of an incompressible, inviscid fluid with surface tension on varying bottoms was researched. The effects of different bottoms on the nonlinear surface waves were analyzed. The waterfall plots of the wave were drawn with Matlab according to the numerical simulation of the fKdV equation with the pseudo-spectral method. From the waterfall plots, the results are obtained as follows: for the convex bottom, the waves system can be viewed as a combination of the effects of forward-step forcing and backwardstep forcing, and these two wave systems respectively radiate upstream and downstream without mutual interaction. Nevertheless, the result for the concave bottom is contrary to the convex one. For some combined bottoms, the wave systems can be considered as the combination of positive forcing and negative forcing. [ABSTRACT FROM AUTHOR]

A rigorous analysis of the resonant characteristics for a broad wall waveguide slot by using the finite-difference time-domain method is presented. Four types of slots including a radiating longitudinal shunt slot, a longitudinal/transverse coupling slot, a centered-inclined coupling slot and a compound coupling slot are analyzed. Lots of slot characteristics such as the resonant length, scattering parameters and normalized admittance in different off- sets, tilt angles or slot sizes are obtained. Because the shape of slots is a rectangle with rounded ends in practical fabrication, an accurate modeling and computation for the slots with rounded ends is implemented, and the resonant lengths calculated coincide well with the Stegen's measured data and method of moments results. From these computed results, it is found that all the resonant characteristics of the slots with rounded ends are significantly different from those with normal rectangular ends. [ABSTRACT FROM AUTHOR]

The antihypertensive effect of vanylidilol, a new α/β-adrenoceptor antagonist with endothelium-dependent and K[sup +] -channel-opening activities, was investigated in normotensive and hypertensive Wistar rats. Vanylidilol competitively antagonized (–)isoproterenol-induced positive chronotropic effects, inotropic effects, and tracheal relaxation effects in isolated rat right atria, left atria, and guinea pig tracheal strips in a concentration-dependent manner. Vanylidilol’s apparent pA[sub 2] values were 6.36 ± 0.08 (right atria), 6.41 ± 0.07 (left atria), and 6.31 ± 0.06 (trachea). Vanylidilol also produced a competitive antagonism of phenylephrine-induced contraction in the isolated rat aorta with pA[sub 2] values of 6.79 ± 0.18. In the radioligand binding assay, vanylidilol inhibited [[sup 3] H]CGP-12177 binding to rat ventricle and lung tissues and [[sup 3] H]prazosin binding to brain membranes with Ki values of 535.17, 2,066.69, and 431.11, respectively. In isolated rat thoracic aorta, vanylidilol’s vasorelaxant effects on phenylephrine (10 μmol/l)-induced contractions were attenuated by removing endothelium and by the presence of L -N[sup G] -nitro arginine methyl ester (L-NAME; 100 μmol/l), methylene blue (10 μmol/l), 1H-[1,2,4]oxadiazolol[4,3,-a] quinoxalin-1-one (ODQ; 10 μmol/l), tetraethylammonium (10 mmol/l), glibenclamide (1 μmol/l), apamin (1 μmol/l), and charybdotoxin (0.1 μmol/l). In addition, vanylidilol, in an equally antagonistic activity, inhibited phenylephrine-induced phasic and tonic contractions. Intravenous vanylidilol further reduced mean blood pressure in pentobarbital-anesthetized normotensive Wistar rats in a dose-dependent manner. The oral administration of vanylidilol to conscious spontaneously hypertensive rats had a long-lasting hypotensive effect on the heart rate and decreased it in a dose-dependent manner. Furthermore, vanylidilol’s vasodilator effect can be attributed in part to the release of NO or NO-related substance from vascular endothelium, while the endothelium-independent mechanism involved in vanylidilol’s relaxation is probably linked to the activation of the K[sup +] channels and the α-adrenoceptor blocking activity in these vessels. Copyright © 2004 S. Karger AG, Basel [ABSTRACT FROM AUTHOR]

Abstract In rat cerebellar granule cells, glutamate induced rapid activation of c-Jun N-terminal kinase (JNK) and p38 kinase to phosphorylate c-Jun (at Ser63) and p53 (at Ser15), respectively, and a subsequent marked increase in activator protein-1 (AP-1) binding that preceded apoptotic death. These glutamate-induced effects and apoptosis could largely be prevented by long-term (7 days) pretreatment with 0.5–2 mm lithium, an antibipolar drug. Glutamate's actions could also be prevented by known blockers of this pathway, MK-801 (an NMDA receptor blocker), SB 203580 (a p38 kinase inhibitor) and curcumin (an AP-1 binding inhibitor). The concentration- and time-dependent suppression of glutamate's effects by lithium and curcumin correlated well with their neuroprotective effects. These results suggest a prominent role of JNK and p38, as well as their downstream AP-1 binding activation and p53 phosphorylation in mediating glutamate excitotoxicity. Moreover, the neuroprotective effects of lithium are mediated, at least in part, by suppressing NMDA receptor-mediated activation of the mitogen-activated protein kinase pathway. [ABSTRACT FROM AUTHOR]

In this paper, the influence of viewing distance on subjective assessment of the impairment in video sequences is investigated. Subjective tests using the double-stimulus impairment scale variant II (DSIS II) method have been conducted at viewing distances of 5H (where H stands for the screen height) and 3H, respectively. Several statistical measures have been used to analyze the influence, including correlations and ANOVA (Analysis of Variance) tests. The results reveal that there is a very high correlation between the subjective scores, the variances are similar under the two viewing distances, the means of subjective data at these two viewing distances are the same, and there is no interaction between the viewing distance and the other two factors, i.e., the codec system and the source sequence. Throughout the tests, there is no evidence that a closer viewing distance such as 3H will vary the subjective test result statistically significantly. [ABSTRACT FROM AUTHOR]

Lithium, the major drug used to treat manic depressive illness, robustly protects cultured rat brain neurons from glutamate excitotoxicity mediated by N-methyl-D-aspartate (NMDA) receptors. The lithium neuroprotection against glutamate excitotoxiciy is long-lasting, requires long-term pretreatment and occurs at therapeutic concentrations of this drug. The neuroprotective mechanisms involve inactivation of NMDA receptors, decreased expression of pro-apoptotic proteins, p53 and Bax, enhanced expression of the cytoprotective protein, Bcl-2, and activation of the cell survival kinase, Akt. In addition, lithium pretreatment suppresses glutamate-induced loss of the activities of Akt, cyclic AMP-response element binding protein (CREB), c-Jun – N-terminal kinase (JNK) and p38 kinase. Lithium also reduces brain damage in animal models of neurodegenerative diseases in which excitotoxicity has been implicated. In the rat model of stroke using middle cerebral artery occlusion, lithium markedly reduces neurologic deficits and decreases brain infarct volume even when administered after the onset of ischemia. In a rat Huntington's disease model, lithium significantly reduces brain lesions resulting from intrastriatal infusion of quinolinic acid, an excitotoxin. Our results suggest that lithium might have utility in the treatment of neurodegenerative disorders in addition to its common use for the treatment of bipolar depressive patients. [ABSTRACT FROM AUTHOR]

Proposes a generalized framework of median based switching schemes, called multi-state median filter for signal restoration and filtering. Description of impulse noise model; Review on the center weighted median filter; Filtering framework; Evaluation results to demonstrate the performance of the proposed approach.

Proposes a novel postprocessing technique for reducing blocking artifacts in low-bit-rate transform coded images. Quantization process to alleviate the accuracy loss of transform coefficients; Masking effect in order to preserve image details; Satisfactory performance of proposed postfiltering technique.