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In this paper, the generation of relativistic electron mirrors (REM) and the reflection of an ultra-short laser off the mirrors are discussed, applying two-dimension particle-in-cell simulations. REMs with ultra-high acceleration and expanding velocity can be produced from a solid nanofoil illuminated normally by an ultra-intense femtosecond laser pulse with a sharp rising edge. Chirped attosecond pulse can be produced through the reflection of a counter-propagating probe laser off the accelerating REM. In the electron moving frame, the plasma frequency of the REM keeps decreasing due to its rapid expansion. The laser frequency, on the contrary, keeps increasing due to the acceleration of REM and the relativistic Doppler shift from the lab frame to the electron moving frame. Within an ultra-short time interval, the two frequencies will be equal in the electron moving frame, which leads to the resonance between laser and REM. The reflected radiation near this interval and corresponding spectra will be amplified due to the resonance. Through adjusting the arriving time of the probe laser, a certain part of the reflected field could be selectively amplified or depressed, leading to the selective adjustment of the corresponding spectra.
This report is on the synthesis by electrospinning of multiferroic core-shell nanofibers of strontium hexaferrite and lead zirconate titanate or barium titanate and studies on magneto-electric (ME) coupling. Fibers with well-defined core–shell structures showed the order parameters in agreement with values for nanostructures. The strength of ME coupling measured by the magnetic field-induced polarization showed the fractional change in the remnant polarization as high as 21%. The ME voltage coefficient in H-assembled films showed the strong ME response for the zero magnetic bias field. Follow-up studies and potential avenues for enhancing the strength of ME coupling in the core–shell nanofibers are discussed.
Earlier studies examining structural brain abnormalities associated with cognitively derived subgroups were mainly cross-sectional in design and had mixed findings. Thus, we obtained cross-sectional and longitudinal data to characterize the extent and trajectory of brain structure abnormalities underlying distinct cognitive subtypes (“preserved,” “deteriorated,” and “compromised”) seen in psychotic spectrum disorders.
Data from 364 subjects (225 patients with psychotic conditions and 139 healthy controls) were first used to determine the relationship of cognitive subtypes with cross-sectional measures of subcortical volume and cortical thickness. To probe neurodevelopmental abnormalities, brain structure laterality was examined. To examine whether neuroprogressive abnormalities persist, longitudinal brain structural changes over 5 years were examined within a subset of 101 subjects. Subsequent discriminant analysis using the identified brain measures was performed on an independent subject group.
Cross-sectional comparisons showed that cortical thinning and limbic volume reductions were most widespread in “deteriorated” cognitive subtype. Laterality comparisons showed more rightward amygdala lateralization in “compromised” than “preserved” subtype. Longitudinal comparisons revealed progressive hippocampal shrinkage in “deteriorated” compared with healthy controls and “preserved” subtype, which correlated with worse negative symptoms, cognitive and psychosocial functioning. Post-hoc discrimination analysis on an independent group of 52 subjects using the identified brain structures found an overall accuracy of 71% for classification of cognitive subtypes.
These findings point toward distinct extent and trajectory of corticolimbic abnormalities associated with cognitive subtypes in psychosis, which can allow further understanding of the biological course of cognitive functioning over illness course and with treatment.
The majority of neuroimaging studies reported smaller hippocampal volumes in patients with posttraumatic stress disorder (PTSD). Our previous study found that PTSD is associated with selective volume loss of the CA3/dentate gyrus subfields However, the causality of smaller hippocampal volumes and PTSD cannot be determined in these studies because of the cross-sectional nature of them. The purpose of this longitudinal study was to determine if PTSD caused hippocampal subfields volume loss following traffic accidents. Volumes of hippocampal subfields in thirty seven traffic accident survivors were measured using 3T MRI in one week after accident, and twenty five of them completed one year follow-up MRI scan. Fourteen participants met the PTSD diagnosis in one year follow-up while other eleven did not met PTSD diagnosis criteria. PTSD was significantly associated with volumes reduction of CA3/dentate gyrus subfield (β=0.244 p=0.017) while other subfields were spared. It also shown volume loses of Entorhinal Cortex (ERC) of both side in one year follow-up for the whole sample (mean volume reduction: right 19.25mm3, left 22.04 mm3). But no association has been found between PTSD and ERC volume alteration. The findings indicate for the first time in humans that selective volume loss of the CA3/dentate gyrus subfields is the results but not the risk factor of PTSD. It also suggested that ERC may also be a stress sensitive region.
Post-stroke depression (PSD) is the most common psychiatric complication facing stroke survivors and has been associated with increased distress, physical disability, poor rehabilitation, and suicidal ideation. However, the pathophysiological mechanisms underlying PSD remain unknown, and no objective laboratory-based test is available to aid PSD diagnosis or monitor progression.
Here, an isobaric tags for relative and absolute quantitation (iTRAQ)-based quantitative proteomic approach was performed to identify differentially expressed proteins in plasma samples obtained from PSD, stroke, and healthy control subjects.
The significantly differentiated proteins were primarily involved in lipid metabolism and immunoregulation. Six proteins associated with these processes – apolipoprotein A-IV (ApoA-IV), apolipoprotein C-II (ApoC-II), C-reactive protein (CRP), gelsolin, haptoglobin, and leucine-rich alpha-2-glycoprotein (LRG) – were selected for Western blotting validation. ApoA-IV expression was significantly upregulated in PSD as compared to stroke subjects. ApoC-II, LRG, and CRP expression were significantly downregulated in both PSD and HC subjects relative to stroke subjects. Gelsolin and haptoglobin expression were significantly dysregulated across all three groups with the following expression profiles: gelsolin, healthy control > PSD > stroke subjects; haptoglobin, stroke > PSD > healthy control.
Early perturbation of lipid metabolism and immunoregulation may be involved in the pathophysiology of PSD. The combination of increased gelsolin levels accompanied by decreased haptoglobin levels shows promise as a plasma-based diagnostic biomarker panel for detecting increased PSD risk in post-stroke patients.
Increasing evidence indicates that major depressive disorder (MDD) is associated with cognitive as well as mood disturbances.
To evaluate cognitive function and white matter structure, resting-state brain function in first-episode, treatmentnaive patients with MDD.
To explore brain structure and function mechanisms of cognitive impairment in MDD.
46 Han Chinese MDD patients aged 18–45 year and 46 controls were assessed by a series of validated test procedures.Then, 30 patients and 30 controls were obtained by MRI scan.White matter abnormalities evaluated using diffusion tensor imaging (DTI) were analyzed using tract based spatial statistics (TBSS) and resting-state brain function was evaluated using regional homogeneity (ReHo) analysis.
Cognitive impairment in patients with MDD was demonstrated by reduced accuracy in the Wisconsin Card Sorting test (WSCT) and to a lesser extent the Continuous Performance test (CPT) and Trail Making tests (TMT). White matter abnormalities found in the left cerebellum, and resting-state abnormalities present in the left inferior parietal gyrus, left anterior cingulate nucleus and left hippocampal gyrus were associated with impaired performance in the WSCT and CPT tests. We also showed that poor WSCT performance was associated with increased interconnectivity between the left ventral anterior cingulate nucleus and the medial frontal lobe areas.
The present study indicates cognitive disturbances in patients with MDD are associated with white matter and resting-state changes and altered interconnections in specific brain areas.
To explore the feature of functional connectivity of default mode network (DMN), central-executive network(CEN), and salience network (SN) in patients with schizophrenia during a resting state by functional magnetic resonance imaging (fMRI).
The SPM8, DPARSFA, conn, REST softwares combined with data-driven region of interest analysis were used to compare the functional connectivity (FC) of the DMN, CEN, and SN in 74 patients with schizophrenia(SZ) and 79 age- and gender-matched normal controls(NC). Medial prefrontal cortex(MPFC)was selected as seed region for identifying DMN and CEN; right anterior insula(rAI) for SN.
Compared with NC, SZ showed increased FC with bilateral dorsolateral prefrontal cortex(DLPFC) and bilateral putamen of the MPFC, and increased FC with left middle frontal cortex and precuneus/ posterior cingulate cortex(Pcu/PCC) of the rAI. SZ also showed enhanced interconnectivity strengths of CEN-DMN, CEN-SN, and DMN-SN(p>0.05). Correlation analyses showed that the increased FC between MPFC and left DLPFC significantly negatively correlated with PANSS-negative symptoms(r=-0.224,p=0.030) and increased FC between rAI and Pcu/PCC significantly correlated with PANSS-positve symptoms (r=0.243,p=0.020).
This study provides evidence for resting state functional abnormalities of DMN, CEN, and SN in schizophrenia patients. These aberrant functional connectivities in some key brain regions of the three network could be responsible for the schizophrenic symptoms.
Planning ability as a critical component of executive function has been used to investigate prefrontal cortex (PFC) function in Schizophrenia patients by several neuroimaging studies. However, the changes of PFC activation after effective antipsychotic treatment are still unclear.
The aim of this study is to explore whether there is any variation in the prefrontal hemodynamic response during Tower of London test after 6 weeks’ antipsychotic treatment in schizophrenia patients, and the relationship between the changes in PFC activation and some demographic factors as well as the severity of the patients’ psychiatric symptoms.
40 patients with first-episode schizophrenia were recruited for the present study. 28-channel NIRS (near infrared spectroscopy) was used to measure changes in hemoglobin concentration in the prefrontal cortical surface area during Tower of London (TOL) test—a classic neuropsychological test for planning abilities. The patients were examined before treatment and after six weeks’ treatment with second-generation antipsychotic medicines.
After the short-term treatment, the patients’ TOL test performance and the activations in PFC during the task period did not differ from baseline (P>0.05), although the psychiatric symptoms of the patients were improved significantly(positive subscale score 18.25±2.86 & 12.75±2.60; general psychopathology 33.67±3.65 & 27.00±3.67; PANSS total score 72.25±7.07 & 55.42±7.53; P<0.001).
It suggests that the impairment of cognitive function and the function of the PFC of schizophrenia patients would not be improved with the improvement of psychiatric symptoms, as further support the hypothesis that PFC damage is a durable impairment for schizophrenia.
In this study, we aimed to identify protein molecules in the hypothalamus in the female rats injected exogenous androgen before sexual differentiation.
Neonatal female SD rats were randomly divided into two groups: experimental group and control female group. Four neonatal male SD rats were control male group. All animals were subjected to intraperitoneal injection of testosterone propionate as experimental group or aseptic oil as control. The rats were sacrificed 90 days after the injection and the brains were collected. 2-DE were performed in order to establish profiles of proteome from rat hypothalamus and followed by MALDITOF- TOF mass spectrometry was used to identify proteins differentially expressed in rat hypothalamus from experimental group as compared to normal control group.
11 differential spots were cut off from the Silver stained gel, and 9 of the spots were identified, which were Dihydropyrimidinase-like 3 (DPYSL3), heterogeneous nuclear ribonucleoprotein K(hnRNP K), Profilin2, Triosephosphate isomerase 1(Tpi 1), Carbonic anhydrase II(CA II), Annexin A3, Protein disulfide isomerase associated 3 (PDIA3), Creatine kinase-B and Secernin 1.
The results of the present study indicate that the development of sexual differentiation may be associated with the alteration in the expression of a large number of cytosolic proteins in the hypothalamus.
We examine the scaling of the two-point correlation function for
, the energy dissipation rate, over a range of values of the separation
between the two points and the Taylor microscale Reynolds number
. The correlation function is estimated from hot-wire measurements in grid turbulence, along the axes of wakes and jets, and along the centreline of a fully developed channel flow. When
exceeds a value of approximately 300, a condition which is achieved for both plane and circular jets, the correlation function collapses over nearly all values of
when the normalization uses Kolmogorov scales. However, there is no collapse in either the power-law range or dissipative range when the normalization is on the integral (or external) length scale, which indicates that there is no self-similarity based on external scales. Although the maximum value of
is not much larger than
, the behaviour of the energy dissipation correlation function on the axes of plane and circular jets seems consistent with the first similarity hypothesis of Kolmogorov (Dokl. Akad. Nauk SSSR, vol. 30, 1941, pp. 299–303) but not with the revised phenomenology of Kolmogorov (J. Fluid Mech., vol. 13, 1962, pp. 82–85).
The present study identified the neural mechanism of risky decision-making in Internet gaming disorder (IGD) under a probability discounting task.
Independent component analysis was used on the functional magnetic resonance imaging data from 19 IGD subjects (22.2 ± 3.08 years) and 21 healthy controls (HC, 22.8 ± 3.5 years).
For the behavioral results, IGD subjects prefer the risky to the fixed options and showed shorter reaction time compared to HC. For the imaging results, the IGD subjects showed higher task-related activity in default mode network (DMN) and less engagement in the executive control network (ECN) than HC when making the risky decisions. Also, we found the activities of DMN correlate negatively with the reaction time and the ECN correlate positively with the probability discounting rates.
The results suggest that people with IGD show altered modulation in DMN and deficit in executive control function, which might be the reason for why the IGD subjects continue to play online games despite the potential negative consequences.
In order to map quantitative trait loci (QTLs) for allometries of body compositions and metabolic traits in chicken, we phenotypically characterize the allometric growths of multiple body components and metabolic traits relative to BWs using joint allometric scaling models and then establish random regression models (RRMs) to fit genetic effects of markers and minor polygenes derived from the pedigree on the allometric scalings. Prior to statistically inferring the QTLs for the allometric scalings by solving the RRMs, the LASSO technique is adopted to rapidly shrink most of marker genetic effects to zero. Computer simulation analysis confirms the reliability and adaptability of the so-called LASSO-RRM mapping method. In the F2 population constructed by multiple families, we formulate two joint allometric scaling models of body compositions and metabolic traits, in which six of nine body compositions are tested as significant, while six of eight metabolic traits are as significant. For body compositions, a total of 14 QTLs, of which 9 dominant, were detected to be associated with the allometric scalings of drumstick, fat, heart, shank, liver and spleen to BWs; while for metabolic traits, a total of 19 QTLs also including 9 dominant be responsible for the allometries of T4, IGFI, IGFII, GLC, INS, IGR to BWs. The detectable QTLs or highly linked markers can be used to regulate relative growths of the body components and metabolic traits to BWs in marker-assisted breeding of chickens.
This paper focus on the mechanical and martensitic transformation behaviors of axially functionally graded shape memory alloy (AFG SMA) beams. It is taken into consideration that material properties, such as austenitic elastic modulus, martensitic elastic modulus, critical transformation stresses and maximum transformation strain vary continuously along the longitudinal direction. According to the simplified linear SMA constitutive equations and Bernoulli-Euler beam theory, the formulations of stress, strain, martensitic volume fraction and governing equations of the deflection, height and length of transformed layers are derived. Employing the Galerkin’s weighted residual method, the governing differential equation of the deflection is solved. As an example, the bending behaviors of an AFG SMA cantilever beam subjected to an end concentrated load are numerically analyzed using the developed model. Results show that the mechanical and martensitic transformation behaviors of the AFG SMA beam are complex after the martensitic transformation of SMA occurs. The influences of FG parameter on the mechanical behaviors and geometrical shape of transformed regions are obvious, and should be considered in the design and analysis of AFG SMA beams in the related regions.
Enhancing the supply of arginine (Arg), a semi-essential amino acid, has positive effects on immune function in dairy cattle experiencing metabolic stress during early lactation. Our objective was to determine the effects of Arg supplementation on biomarkers of liver damage and inflammation in cows during early lactation. Six Chinese Holstein lactating cows with similar BW (508 ± 14 kg), body condition score (3.0), parity (4.0 ± 0), milk yield (30.6 ± 1.8 kg) and days in milk (20 ± days) were randomly assigned to three treatments in a replicated 3 × 3 Latin square design balanced for carryover effects. Each period was 21 days with 7 days for infusion and 14 days for washout. Treatments were (1) Control: saline; (2) Arg group: saline + 0.216 mol/day l-Arg; and (3) Alanine (Ala) group: saline + 0.868 mol/day l-Ala (iso-nitrogenous to the Arg group). Blood and milk samples from the experimental cows were collected on the last day of each infusion period and analyzed for indices of liver damage and inflammation, and the count and composition of somatic cells in milk. Compared with the Control, the infusion of Arg led to greater concentrations of total protein, immunoglobulin M and high density lipoprotein cholesterol coupled with lower concentrations of haptoglobin and tumor necrosis factor-α, and activity of aspartate aminotransferase in serum. Infusion of Ala had no effect on those biomarkers compared with the Control. Although milk somatic cell count was not affected, the concentration of granulocytes was lower in response to Arg infusion compared with the Control or Ala group. Overall, the biomarker analyses indicated that the supplementation of Arg via the jugular vein during early lactation alleviated inflammation and metabolic stress.
Some studies have shown that the excessive metabolic heat production is the primary cause for dead chicken embryos during late embryonic development. Increasing heat shock protein (HSP) expression and adjusting metabolism are important ways to maintain body homeostasis under heat stress. This study was conducted to investigate the effects of in ovo injection (IOI) of vitamin C (VC) at embryonic age 11th day (E11) on HSP and metabolic genes expression. A total of 320 breeder eggs were randomly divided into normal saline and VC injection groups. We detected plasma VC content and rectal temperature at chick’s age 1st day, and the mRNA levels of HSP and metabolic genes in embryonic livers at E14, 16 and 18, analysed the promoter methylation levels of differentially expressed genes and predicted transcription factors at the promoter regions. The results showed that IOI of VC significantly increased plasma VC content and decreased rectal temperature (P < 0.05). In ovo injection of VC significantly increased heat shock protein 60 (HSP60) and pyruvate dehydrogenase kinase 4 (PDK4) genes expression at E16 and PDK4 and secreted frizzled related protein 1 (SFRP1) at E18 (P < 0.05). At E16, IOI of VC significantly decreased the methylation levels of total CpG sites and −336 CpG site in HSP60 promoter and −1137 CpG site in PDK4 promoter (P < 0.05). Potential binding sites for nuclear factor-1 were found around −389 and −336 CpG sites in HSP60 promoter and potential binding site for specificity protein 1 was found around −1137 CpG site in PDK4 promoter. Our results suggested that IOI of VC increased HSP60, PDK4 and SFRP1 genes expression at E16 and 18, which may be associated with the demethylation in gene promoters. Whether IOI of VC could improve hatchability needs to be further verified by setting uninjection group.
In vivo positron emission tomography (PET) using [C11]-labeled Pittsburgh Compound B ([C11]PiB) has previously been shown to detect amyloid-β (Aβ) in late-onset Alzheimer disease (LOAD) brain; however, the sensitivity of this technique for detecting β-amyloidosis in autosomal dominant Alzheimer disease (ADAD) has not been systematically investigated. To validate [C11]PiB PET as a useful biomarker of β-amyloidosis, we measured the cortical and regional standardized uptake value ratios (SUVRs) in 16 ADAD and 15 LOAD cases and compared them with histopathologic measures of β-amyloidosis in postmortem brain. The PiB-PET data were obtained between 40–70 min after bolus injection of ∼15 mCi of [11C]PiB. MRI and PiB-PET images were co-registered and SUVRs were generated for several brain regions. Using Aβ immunohistochemistry (10D5, Eli Lilly), the burden of Aβ plaques was quantified in 16 regions of interest using an area fraction fractionator probe (Stereo Investigator, MicroBrightfield, VT). There were regional variations in Aβ plaque burden with highest densities observed in the neocortical areas and the striatum. On spearman correlations, in vivo PiB-PET correlated with postmortem Aβ plaque burden in both LOAD and ADAD, with strongest correlations seen in neocortical areas. In summary, [C11]PiB-PET has utility as a biomarker in both ADAD and LOAD.
This presentation will enable the learner to:
1.Discuss how PET-PiB beta-amyloid imaging is used as a potential biomarker of Alzheimer disease (AD)
2.Correlate postmortem neuropathologic evidence of beta-amyloidosis with PET-PiB data, and learn that PET-PiB is a potentially useful tool to detect beta-amyloidosis in presymptomatic and symptomatic individuals
To retrospectively study the primary laryngeal lymphoma cases in China reported in Chinese-language literature.
Chinese-language literature was searched for papers on primary laryngeal lymphoma published in the last 25 years.
The selected papers comprised a total of 115 cases. The male-to-female ratio was 3.4:1. Non-Hodgkin's lymphoma was the exclusive pathological type. The estimated 3-year, 5-year and 10-year survival rates were 70.9 ± 6.4 per cent, 63.4 ± 7.6 per cent and 56.4 ± 9.5 per cent respectively, as determined by Kaplan–Meier analysis. B-cell non-Hodgkin's lymphoma patients had a better prognosis than T-cell non-Hodgkin's lymphoma patients (p = 0.032). Patients with lymph node involvement at diagnosis had a poorer prognosis (p < 0.01).
Primary laryngeal lymphoma is a rare disease with no specific clinical features. More than one biopsy might be needed to obtain the correct diagnosis. Proper treatment could lead to promising outcomes. The T-cell subtype and lymph node involvement at diagnosis might indicate worse prognosis.