Controlling coherence using the internal structure of hard pi pulses

The tiny difference between hard pi pulses and their delta-function approximation can be exploited to control coherence. Variants on the magic echo that work despite a large spread in resonance offsets are demonstrated using the zeroth- and first-order average Hamiltonian terms, for 13-C NMR in C60. The 29-Si NMR linewidth of Silicon has been reduced by a factor of about 70,000 using this approach, which also has potential applications in magnetic resonance microscopy and imaging of solids.Comment: 4 pages, 4 color figure

Protection of p-coumaric acid against chronic stress-induced neurobehavioral deficits in mice via activating the PKA-CREB-BDNF pathway

There is a body of evidence to suggest that chronic stress modulates neurochemical homeostasis, alters neuronal structure, inhibits neurogenesis and contributes to development of mental disorders. Chronic stress-associated mental disorders present common symptoms of cognitive impairment and depression with complex disease mechanisms. P-coumaric acid (p-CA), a natural phenolic compound, is widely distributed in vegetables, cereals and fruits. P-CA exhibits a wide range of health-related effects, including anti-oxidative-stress, anti-mutagenesis, anti-inflammation and anti-cancer activities. The current study aims to evaluate the therapeutic potential of p-CA against stress-associated mental disorders. We assessed the effect of p-CA on cognitive deficits and depression-like behavior in mice exposed to chronic restraint stress (CRS); we used network pharmacology, biochemical and molecular biological approaches to elucidate the underlying molecular mechanisms. CRS exposure caused memory impairments and depression-like behavior in mice; p-CA administration attenuated these CRS-induced memory deficits and depression-like behavior. Network pharmacology analysis demonstrated that p-CA was possibly involved in multiple targets and a variety of signaling pathways. Among them, the protein kinase A (PKA) - cAMP-response element binding protein (CREB) - brain derived neurotrophic factor (BDNF) signaling pathway was predominant and further characterized. The levels of PKA, phosphorylated CREB (pCREB) and BDNF were significantly lowered in the hippocampus of CRS mice, suggesting disruption of the PKA-CREB-BDNF signaling pathway signaling pathway; p-CA treatment restored the signaling pathway. Furthermore, CRS upregulated expression of proinflammatory cytokines in hippocampus, while p-CA reversed the CRS-induced effects. Our findings suggest that p-CA will offer therapeutic benefit to patients with stress-associated mental disorders

Chinese medicine, Qijudihuang pill, mediates cholesterol metabolism and regulates gut microbiota in high-fat diet-fed mice, implications for age related macular degeneration

Background: Traditional Chinese Medicines have been used for thousands of years but without any sound empirical basis. One such preparation is the Qijudihuang pill (QP), a mixture of eight herbs, that has been used in China for the treatment of various conditions including age-related macular degeneration (AMD), the most common cause of blindness in the aged population. In order to explain the mechanism behind the effect of QP, we used an AMD model of high-fat diet (HFD) fed mice to investigate cholesterol homeostasis, oxidative stress, inflammation and gut microbiota.Methods: Mice were randomly divided into three groups, one group was fed withcontrol diet (CD), the other two groups were fed with high-fat-diet (HFD). OneHFD group was treated with QP, both CD and the other HFD groups were treatedwith vehicles. Tissue samples were collected after the treatment. Cholesterollevels in retina, retinal pigment epithelium (RPE), liver and serum weredetermined using a commercial kit. The expression of enzymes involved incholesterol metabolism, inflammation and oxidative stress was measured withqRT-PCR. Gut microbiota was analyzed using 16S rRNA sequencing.Results: In the majority of the lipid determinations, analytes were elevated by HFD but thiswas reversed by QP. Cholesterol metabolism including the enzymes of bile acid (BA) formationwas suppressed by HFD but again thiswas reversed by QP. BAs play amajor role in signaling between host andmicrobiome and this is disrupted by HFD resulting in major changes in the composition of colonic bacterial communities. Associated with these changes are predictions of the metabolic pathway complexity and abundance of individual pathways. These concerned substrate breakdowns, energy production and the biosynthesis of proinflammatory factors but were changed back to control characteristics by QP.Conclusion: We propose that the ability of QP to reverse these HFD-inducedeffects is related to mechanisms acting to lower cholesterol level, oxidative stress and inflammation, and to modulate gut microbiota

The Intrinsic Origin of Spin Echoes in Dipolar Solids Generated by Strong Pi Pulses

In spectroscopy, it is conventional to treat pulses much stronger than the linewidth as delta-functions. In NMR, this assumption leads to the prediction that pi pulses do not refocus the dipolar coupling. However, NMR spin echo measurements in dipolar solids defy these conventional expectations when more than one pi pulse is used. Observed effects include a long tail in the CPMG echo train for short delays between pi pulses, an even-odd asymmetry in the echo amplitudes for long delays, an unusual fingerprint pattern for intermediate delays, and a strong sensitivity to pi-pulse phase. Experiments that set limits on possible extrinsic causes for the phenomena are reported. We find that the action of the system's internal Hamiltonian during any real pulse is sufficient to cause the effects. Exact numerical calculations, combined with average Hamiltonian theory, identify novel terms that are sensitive to parameters such as pulse phase, dipolar coupling, and system size. Visualization of the entire density matrix shows a unique flow of quantum coherence from non-observable to observable channels when applying repeated pi pulses.Comment: 24 pages, 27 figures. Revised from helpful referee comments. Added new Table IV, new paragraphs on pages 3 and 1

Chitosan-based melatonin bilayer coating for maintaining quality of fresh-cut products

This work was designed to develop the chitosan-based melatonin layer-by-layer assembly (CMLLA) via the inclusion method. The structural characterizations and interaction present in CMLLA were investigated by the scanning electron microscope (SEM), X-ray diffraction (XRD) and Fourier Transform-Infrared spectroscopy (FTIR). The ratio of chitosan (CH) to carboxymethylcellulose (CMC) greatly influenced the mechanical properties, including the tensile strength, moisture content and color performance. Results showed that both antioxidant and antimicrobial properties of CMLLA were enhanced with the addition of melatonin (MLT). Furthermore, it was demonstrated that the CMLLA with 1.2 % (w/v) CH, 0.8 % (w/v) CMC and 50 mg/L MLT better contributed to the delay of chlorophyll degradation and the maintenance of shelf-life quality. Results from this study might open up new insights into the approaches of quality improvement of postharvest fresh products by incorporating the natural antioxidant compounds into natural polymers

The effects of text direction of different text lengths on Chinese reading

Abstract This study investigates the effects of text direction (horizontal and vertical) and length (long and short) on Chinese reading performance. The experiment enrolled 68 university students aged 19–29 years who were asked to read articles. We recorded reading times and measured recall after reading using a memory test and measured task load using the NASA-TLX scale. The results show that horizontal text was read faster than vertical text. When reading long texts, horizontal reading has a better memory effect than vertical reading. When reading short texts, the effect of text direction on memory was not significant. Moreover, the mental, physical, and temporal demands of horizontal text were lower than those of vertical text. These findings contribute to a better understanding of the impact of text direction, provide valuable suggestions for Chinese typography, and help readers obtain better reading outcomes

Disparities in the Local Management of Breast Cancer in the US according to Health Insurance Status.

Although standard practice guidelines for breast cancer are clear, the interplay between insurance and practice patterns for the US is poorly defined. This study was performed to test for associations between patient insurance status and presentation of breast cancer as well as local therapy patterns in the US, via a large national dataset. We queried the NCI Surveillance, Epidemiology, and End Results data base for breast cancer cases diagnosed from 2007 to 2011 in women aged 18-64 with nonmetastatic ductal/lobular cancers, treated surgically. We tested for associations between insurance status (insured/Medicaid/uninsured) and choice of surgical procedure (mastectomy/breast conserving surgery [BCS]), omission of radiotherapy (RT) following BCS, and administration of post-mastectomy radiation (PMRT). There were 129,565 patients with localized breast cancer analyzed. The health insurance classification included insured (84.5%), Medicaid (11.5%), uninsured (2.1%) and unknown (1.9%). Medicaid or uninsured status was associated with large, node positive tumors, black race, and low income. The BCS rate varied by insurance status: insured (52.2%), uninsured (47.7%), and Medicaid (45.2%), p \u3c 0.001. In multivariable analysis, Medicaid insurance remained significantly associated with receipt of mastectomy (OR [95% CI] = 1.07 [1.03-1.11]), while RT was more frequently omitted after BCS in both Medicaid (OR [95% CI] = 1.14 [1.07-1.21]) and uninsured (OR [95% CI] = 1.29 [1.14-1.47]) patients. Insurance status was associated with significant variations in breast cancer care in the US. Although patient choice cannot be determined from this dataset, departure from standard of care is associated with specific types of insurance coverage. Further investigation into the reasons for these departures is strongly suggested

Disparities in the management and outcome of cervical cancer in the United States according to health insurance status.

INTRODUCTION: Our study sought to characterize the presentation, local management and outcomes of invasive cervical cancer with regard to patient insurance status. METHODS: We queried the NCI-SEER database for invasive cervical cancer cases in patients aged 18-64 from 2007 to 2011. We analyzed clinical and socioeconomic data with regard insurance status (insured, Medicaid, or uninsured). We tested for associations between patient insurance status and treatment with definitive surgery for FIGO IA2-IB1 patients, and treatment with suboptimal radiation therapy (RT) for FIGO IB2-IVA patients (other than combination external beam and brachytherapy). We evaluated overall and cause specific survival according to insurance status. RESULTS: 11,714 cases were analyzed: 60% insured, 31% Medicaid, and 9% uninsured. FIGO III/IV stage at presentation was more frequent with Medicaid (40%) and uninsured (42%) compared to insured patients (28%) (p CONCLUSIONS: Disparities in cervical cancer treatment with regard to insurance status are apparent in a recent cohort of American patients. Later stage at presentation and differences in management partially account for the inferior prognostic outcomes associated with Medicaid and uninsured status