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Laser-driven positron sources, characterized by short pulse width, small focal spot and high energy, are promising for potential applications, e.g. electron–positron collider and positron annihilation spectroscopy. However, the broad divergence angle and wide pulse width during the laser-driven positron transport are extremely unfavorable for achieving high spatiotemporal resolution. In this paper, we propose a novel method to manipulate the positrons by using a left-hand circularly-polarized Laguerre–Gaussian (LG) laser pulse. Using the LG laser with a intensity of 1.2 × 10 21 W c m − 2 and a duration of a few cycles, three-dimensional particle-in-cell simulations reveal that isotropic hot positrons can be effectively captured, collimated, compressed, and accelerated due to the unique field structure of the LG laser. A high-quality positron bunch is obtained with a peak divergence angle of 1 ∘ , an average pulse duration of 0.5 fs, a maximum energy of 450 MeV, and a density of 70 times that of the initial electron source. A damping vibration model is also formulated to explain qualitatively the quality improvement of the positrons.

An all-optical method for generating ultra-intense high-order-mode light pulse is investigated with three-dimensional particle-in-cell simulation. We find that the conversion from a short intense circularly polarized incident Gaussian laser pulse into a transverse magnetic (TM) mode occurs as it propagates into a micro plasma waveguide. The strength of the longitudinal electric field of the excited TM modes can be almost two orders of magnitude higher than that of the original laser. The simulation results show that, for the lower-order modes, the trapped electrons lead to their revolving transverse structures. A linear plasma waveguide model is presented to predict the mode pattern and intensity of the longitudinal electric fields, which are in excellent agreement with those in the simulations. Relativistic-intense high-order-mode light can be useful for many applications, including accelerating charged particles to high energies.

A new generation of high power laser facilities will provide laser pulses with extremely high powers of 10 petawatt (PW) and even 100 PW, capable of reaching intensities of$10^{23}~\\text{W}/\\text{cm}^{2}$in the laser focus. These ultra-high intensities are nevertheless lower than the Schwinger intensity$I_{S}=2.3\\times 10^{29}~\\text{W}/\\text{cm}^{2}$at which the theory of quantum electrodynamics (QED) predicts that a large part of the energy of the laser photons will be transformed to hard Gamma-ray photons and even to matter, via electron–positron pair production. To enable the investigation of this physics at the intensities achievable with the next generation of high power laser facilities, an approach involving the interaction of two colliding PW laser pulses is being adopted. Theoretical simulations predict strong QED effects with colliding laser pulses of${\\geqslant}10~\\text{PW}$focused to intensities${\\geqslant}10^{22}~\\text{W}/\\text{cm}^{2}$.

Objective Previous studies have found that wnt5a promotes β-cell insulin secretion and reduced concentrations in patients with type 2 diabetes. GLP-1RA (Glucagon-like peptide-1 receptor agonists) can regulate insulin secretion. However, the evidence that GLP-1RA affect insulin secretion through the Wnt5a is inconclusive. Therefore, this study aimed to evaluate the effect of GLP-1 RA on wnt5a levels in patients with type 2 diabetes. Methods A total of 56 onset diabetics were selected our study, 29 of them were treated by GLP-1RAs (1.2mg subcutaneous injection once a day, liraglutide, Novo Nordisk), the rest (27 case) treated by Metformin (0.5 g twice a day, Glucophage, Merck). Individuals who were using medications to manage platelet (Aspirin) and cholesterol (Statins) were enrolled and continued treatment throughout the study. Results Our study found that the waist circumference and insulin secretion index in the GLP-1RA intervention group were significantly increased, and the insulin resistance index was lower than that of the control group. More interestingly, the serum Wnt5a protein level increased dramatically after the GLP-1RA intervention, and the level of Secreted frizzled-related protein 5 (Sfrp5) decreased compared with the control group. Multivariate linear regression analysis showed that the change of HOMA-β (Homeostasis model assessment- β) was significantly correlated with the changes of Wnt5a and Sfrp5, and the change of Wnt5a protein was positively correlated with HOMA-β. Conclusion Our results confirmed that GLP-1RA may improve HOMA-β in patients with type 2 diabetes by affecting the level of Wnt5a protein.

Aim Metformin is a first-line therapy for the treatment of Type 2 diabetes mellitus (T2DM), due to its inhibition of hepatic gluconeogenesis. Wingless family member 5a (Wnt5a) was significantly decreased in newly diagnosed T2DM patients and regulates secretion of β cells through the Wnt/calcium signalling cascades. This study aims to investigate how metformin works on glucose-lowering effects in diabetes and whether the mechanism underlying it is associated with Wnt5a. Methods A total of 144 participants were enrolled in this study. Serum Wnt5a levels were measured by an enzyme-linked immunosorbent assay (ELISA). The demographic and clinical parameters were evaluated in normal weight, overweight and obese new-onset T2DM subjects grouped. Results Wnt5a was increased in overweight T2DM patients and obese T2DM patients compared with the levels in normal Body Mass Index (BMI) T2DM. The level of Wnt5a gradually increased after 3 and 6 months of metformin treatment. Among the three groups, the most significant improvement in blood glucose was observed in the obese type 2 diabetic patients, and the improvement showed a significant correlation with Wnt5a protein after patients received metformin treatment. Pearson correlation showed that there was a significant relationship between △2hOGTT and Wnt5a. After further adjusting for sex and age, a significant association existed only between Wnt5a and 2-h oral glucose tolerance test(2hOGTT), and this association was negative. Conclusion Our results indicate that Wnt5a may play a role in the mechanism by which metformin improves blood glucose in patients with type 2 diabetes.

We present experimental results on ion acceleration with circularly polarized, ultrahigh contrast laser pulses focused to peak intensities of 5×1019Wcm−2 onto polymer targets of a few 10 nanometer thickness. We observed spatially and energetically separated protons and carbon ions that accumulate to pronounced peaks around 2 MeV containing as much as 6.5% of the laser energy. Based on particle-in-cell simulation, we illustrate that an early separation of heavier carbon ions and lighter protons creates a stable interface that is maintained beyond the end of the radiation pressure dominated acceleration process.

In Asia, the most frequent type of PPK is Nagashima PPK, with an estimated prevalence of 3.1 per 10 000 population.1 This article summarises the clinical features and molecular findings in three Chinese individuals with isolated diffuse hereditary PPK recruited from a single centre and highlights the significance of genetic testing in reaching an accurate classification and diagnosis. Author contributions All authors contributed equally to the concept or design of the study, acquisition of the data, analysis or interpretation of the data, drafting of the manuscript, and critical revision of the manuscript for important intellectual content. Mutations in the gene encoding SLURP-1 in Mal de Meleda.

Efficient energy boost of the laser-accelerated ions is critical for their applications in biomedical and hadron research. Achiev-able energies continue to rise, with currently highest energies, allowing access to medical therapy energy windows. Here, a new regime of simultaneous acceleration of ~100 MeV protons and multi-100 MeV carbon-ions from plasma micro-channel targets is proposed by using a ~10 20  W/cm 2 modest intensity laser pulse. It is found that two trains of overdense electron bunches are dragged out from the micro-channel and effectively accelerated by the longitudinal electric-field excited in the plasma channel. With the optimized channel size, these “superponderomotive” energetic electrons can be focused on the front surface of the attached plastic substrate. The much intense sheath electric-field is formed on the rear side, leading to up to ~10-fold ionic energy increase compared to the simple planar geometry. The analytical prediction of the optimal channel size and ion maximum energies is derived, which shows good agreement with the particle-in-cell simulations.

Improvements in the porcine genetic map and availability of resource families to study performance traits in pigs have made it possible to reexamine previous findings that linked certain traits to genes or chromosomal regions. Previous studies suggested that chromosomes 4 and 7 may be associated with growth and performance traits. To confirm these previous results, an interval mapping-regression approach was used to determine whether quantitative trait loci (QTL) exist in the Iowa State University reference/resource families. Traits measured were birth weight; body weight at 21 d; weaning weight (weight at 42 d); average daily gain; backfat at the first, 10th, lumbar, and last ribs and average backfat thickness; loin eye area; meat color; marbling; and firmness. The total number of F2 pigs used ranged from 241 to 330 and came from five Chinese X American resource families. Five markers (S0001, SW871, S0175, S0214, and SW445) were genotyped and mapped on chromosome 4, and so were 10 markers (50064, tumor necrosis factor a [TNFalpha], S0102, S0078, S0158, S0066, SW304, SW1083, 50101, and S0212) on chromosome 7. Data were analyzed for each family (breed cross) separately and were also pooled. Experiment-wise thresholds were used to determine significance. Suggestive evidence of QTL on chromosomes 4 and 7 was observed for several traits in pooled and individual family analyses. Suggestive evidence of a QTL with a relatively large effect for average daily gain was detected on chromosome 4 in the pooled analysis. Significant (P <.05) evidence for QTL was seen on chromosome 7 for 10th-rib, last-rib, and average backfat thickness in the pooled data set in a region of the chromosome that was near TNFalpha. These results verify in part that chromosomes 4 and 7 contain QTL for growth and carcass traits.

Objective: This study assesses the effects of a 2005 increase in funding for smoking cessation services on provider participation, patient utilisation of smoking cessation services and cessation outcome at a six-month follow-up. Methods: Analyses are based on existing databases and on a follow-up study among smokers participating in the smoking cessation service. The effect of the policy is evaluated by comparing year 2004 (old policy) with year 2005 (new policy). The generalised estimating equations (GEE) method was conducted to examine the effects of increasing funding for smoking cessation services on monthly smoking cessation services provided per physician and yearly consultations received per patient. Logistic regression was used to examine the effects of increasing funding on smoking cessation outcome. Results: The study found the increased reimbursement rates and medication subsidies for smoking cessation to be positively related to the number of physicians enrolling in the programme (1841 in 2004 vs 3466 in 2005), the number of cessation consultations per month per physician (5.1 vs 14.6) and the number of cessation visits per year per patient (2.0 vs 2.5). Male providers and providers belonging to the private sector were found to offer more cessation consultations. The number of subjects receiving this counselling increased from 22 167 in 2004 to 109 508 in 2005. After adjusting for consumer and provider factors the likelihood of successful quitting among those counselled did not change. Overall, smokers who were older, had attempted to quit in the past year, had lower nicotine dependence, had gone to more smoking cessation service visits, had received consultations in the public sector and were seen by physicians delivering fewer consultations were more likely to have quit smoking at the six-month follow-up. Conclusions: Based on increases in physician enrolment and consultations and the increase in number of subjects receiving counselling and number of visits, the policy of increasing provider incentives and medication subsidies appears to have successfully promoted smoking cessation services.