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On‐treatment EPID images are contaminated with patient‐generated scattered photons. If this component can be accurately estimated, its effect can be removed, and therefore a corresponding in vivo patient dose estimate will be more accurate. Our group previously developed a "tri‐hybrid" (TH) algorithm to provide fast but accurate estimates of patient‐generated photon scatter. The algorithm uses an analytical method to solve for singly‐scattered photon fluence, a modified Monte Carlo hybrid method to solve for multiply‐scattered photon fluence, and a pencil beam scatter kernel method to solve for electron interaction generated scattered photon fluence. However, for efficient clinical implementation, spatial and energy sampling must be optimized for speed while maintaining overall accuracy. In this work, the most significant sampling issues were examined, including spatial sampling settings for the patient voxel size, the number of Monte Carlo histories used in the modified hybrid MC method, scatter order sampling for the hybrid method, and also a range of energy spectrum sampling (i.e., energy bin sizes). The total predicted patient‐scattered photon fluence entering the EPID was compared with full MC simulation (EGSnrc) for validation. Three phantoms were tested with 6 and 18 MV beam energies, field sizes of 4 × 4, 10 × 10, and 20 × 20 cm2, and source‐to‐imager distance of 140 cm to develop a set of optimal sampling settings. With the recommended sampling, accuracy and precision of the total‐scattered energy fluence of the TH patient scatter prediction method are within 0.9% and 1.2%, respectively, for all test cases compared with full MC simulation results. For the mean energy spectrum across the imaging plane, comparison of TH with full MC simulation showed 95% overlap. This study has optimized sampling settings so that they have minimal impact on patient scatter prediction accuracy while maintaining maximum execution speed, a critical step for future clinical implementation.

Iron-based metal phosphides (IMPs) have emerged as a new type of bifunctional electrocatalyst for overall water splitting with high efficiency and good stability. We report IMPs nanoparticles' fabrication with different metal element compositions anchored on phosphorus-doped vertically aligned graphene arrays (IMPs/P-VG), which is successfully achieved by tuning the different phosphates in the electroless plating solution. Compared with other metal ratios of electrocatalysts, Fe0.5Co1.5Ni0.5P/P-VG exhibits the best apparent and intrinsic activity in 1 M KOH, and it also shows good stability up to 12 h without any significant degradation. Moreover, benefiting the unique hierarchical vertical arrays nanostructure of the substrate and the trimetallic phosphides' synergetic effects, the Faraday efficiency of the electrolytic cell based on Fe0.5Co1.5Ni0.5P/P-VG double electrode for the overall water-splitting is up to 90%. This study suggests that proper tuning of the composition of metal elements in IMPs and integrated on compatible substrates can effectively improve the electrocatalytic activity of IMPs for water splitting.

Intercellular communication mediated by a large number of neuromodulators diversifies physiological actions, yet neuromodulation remains poorly understood despite the recent upsurge of genetically encoded transmitter sensors. Here, we report the development of a versatile genetically encoded sensor-based image analysis program (GESIAP) that utilizes MATLAB-based algorithms to achieve high-throughput, high-resolution processing of sensor-based functional imaging data. GESIAP enables delineation of fundamental properties (e.g., transmitter spatial diffusion extent, quantal size, quantal content, release probability, pool size, and refilling rate at single release sites) of transmission mediated by various transmitters (i.e., monoamines, acetylcholine, neuropeptides, and glutamate) at various cell types (i.e., neurons, astrocytes, and other non-neuronal cells) of various animal species (i.e., mouse, rat, and human). Our analysis appraises a dozen of newly developed transmitter sensors, validates a conserved model of restricted non-volume neuromodulatory synaptic transmission, and accentuates a broad spectrum of presynaptic release properties that variegate neuromodulation.

Self-supported non-noble metal based bifunctional electrocatalysts with high catalytic activity and long-term stability in a wide pH range are highly essential for the production of hydrogen and oxygen, remains a great challenge. Herein, a bifunctional electrocatalyst is synthesized via electroless plating of FeCoNiP nanoparticles on self-supported phosphorus-doped vertically aligned graphene arrays (FeCoNiP/P-VG). FeCoNiP/P-VG exhibits an exceptionally high catalytic activity for hydrogen evolution reaction (HER) and oxygen evolution reaction (OER) in a wide pH range, with an overpotential of 81 and 141 mV for HER, and 240 and 409 mV for OER, in 1.0 M KOH and 0.5 M H2SO4 respectively, at current density of 10 mA. It also performs quite low Tafel slope value of 40 mV·dec−1 for HER and 69 mV·dec−1 for OER in 1.0 M KOH. More importantly, it shows prominent stability in acidic and alkaline electrolytes. This study may open a new avenue for the design and fabrication of self-supported bifunctional electrocatalysts for water splitting.

FeCoNiP nanoparticles integrated on vertical P-doped graphene is facilely fabricated on Cu foil (FeCoNiP/PVG/Cu) by one-step electrodeposition as electrocatalyst toward overall water splitting in a wide pH range. The FeCoNiP/PVG/Cu electrocatalyst exhibits low overpotentials (115 and 223 mV) at 10 mA [Formula: see text] cm[Formula: see text] and low Tafel slopes (70 and 76 mV [Formula: see text] dec[Formula: see text] toward hydrogen evolution reaction in 1.0 M KOH and 0.5 M H2SO4, respectively. At the same time, the FeCoNiP/PVG/Cu electrocatalyst exhibits a remarkable activity with overpotential of 361 mV at 50 mA [Formula: see text] cm[Formula: see text] and Tafel slope of 96 mV [Formula: see text] dec[Formula: see text] in 1.0 M KOH toward oxygen evolution reaction, which is even comparable with the noble IrO2 electrocatalyst (370 mV and 80 mV [Formula: see text] dec[Formula: see text]. FeCoNiP/PVG/Cu electrocatalyst also displays a remarkable electrochemical durability to toward HER in both alkaline and acid solutions for at least 15 h, toward OER in alkaline solution for at least 13 h. This work contributes to the research of designing non-noble earth-abundant electrocatalyst with high property in a wide pH range for overall water splitting, thus pushing the development of industrial utilization of water splitting.

Education through scientific research is the most basic and obvious educational logic of postgraduates' ideological and political education, which has the characteristics of scientific research ideal orientation, cognition of scientific spirit, scientific research practice. The integration of scientist's spirit into the ideological and political education of postgraduates from the perspective of education through scientific research is feasible, and the two are compatible with each other in terms of content, coherent in terms of purpose, and manifest in terms of value. At present, under the environment of education through scientific research,scientist's spirit being integrated into the ideological and political education of graduate students faces the dilemma of subject, cognition and practice. We should improve the education through scientific research measures from the aspects of promoting the concept of scientific research education, deepening the spiritual cognition of scientists in connotation, and strengthening the links of scientific research participation in practice. To explore a new way to integrate the spirit of scientists into the ideological and political education of graduate students.

Water splitting is considered as a potential sustainable and green technology for producing mass hydrogen and oxygen. A cost-effective self-supported stable electrocatalyst with excellent electrocatalytic performance in a wide pH range is greatly required for water splitting. This work reports on the synthesis and anchoring of Fe1CoxNiyP nanoparticles on vertically aligned reduced graphene oxide array (VrGO) via electroless plating. The catalytic activity of Fe1CoxNiyP nanoparticles is tuned finely by tailoring the cationic ratio of Co and Ni. Fe1Co2Ni1P/VrGO exhibits the lowest overpotential (109 and 139 mV) at 10 mA cm−2 and lowest tafel slope (133 and 31 mV dec−1) for hydrogen evolution reaction in 1.0 M KOH and 0.5 M H2SO4, respectively. Fe1Co1Ni2P/VrGO exhibits the lowest overpotential (342 mV) at 10 mA cm−2 with lowest tafel slope (60 mV dec−1) for oxygen evolution reaction. The enhanced performance of the electrocatalyst is attributed to improved electrical conductivity, synergistic effects, and beneficial electronic states caused by the appropriate atomic ratio of Co and Ni in the bifunctional electrocatalyst. This study helps to explore the effect of variable cationic ratio in the cost-effective ternary iron group metal phosphides electrocatalysts to achieve enhanced electrocatalytic performance for water splitting in a wide pH range.

Accurate tracking of organ motion during treatment is needed to improve the efficacy of radiation therapy. This work investigates the feasibility of tracking an uncontoured target using the motion detected within a moving treatment aperture. Tracking was achieved with a weighted optical flow algorithm, and three different techniques for updating the reference image were evaluated. The accuracy and susceptibility of each approach to the accumulation of position errors were verified using a 3D-printed tumor (mounted on an actuator) and a virtual treatment aperture. Tumor motion up to 15.8 mm (peak-to-peak) taken from the breathing patterns of seven lung cancer patients was acquired using an amorphous silicon portal imager at ~ 7.5 frames/s. The first approach (INI) used the initial image detected, as a fixed reference, to determine the target motion for each new incoming image, and performed the best with the smallest errors. This method was also the most robust against the accumulation of position errors. Mean absolute errors of 0.16, 0.32, and 0.38 mm were obtained for the three methods, respectively. Although the errors are comparable to other tracking methods, the proposed method does not require prior knowledge of the tumor shape and does not need a tumor template or contour for tracking. Graphical abstract.

Research on cost-effective and high-efficient catalysts for overall water splitting is urgent, and iron group metal borides (IMBs) are a promising candidate. Here, FeCoNiB nanoparticles anchoring on vertically aligned B-doped graphene array (FeCoNiB/BVG) by electroless plating are synthesized for overall water splitting, and FeCoNiB nanoparticles anchoring on other heteroatom-doped graphene substrates (FeCoNiB/XVG, X = N, P, S, O) are prepared for comparison. FeCoNiB/BVG exhibits the best performance with HER and OER overpotential of only 88 mV and 149 mV in 1.0 M KOH, respectively. And FeCoNiB/BVG has a very strong stability for 15 h and the Faraday efficiency of about 94%. The XPS results prove that the best performance of FeCoNiB/BVG is due to the synergistic effect between B in BVG and B in FeCoNiB. This work provides a reference for the rational design of non-noble metal-based electrocatalysts and promotes the application of non-noble metal-based electrocatalysts in the water electrolysis industry.

Disruption of the blood-brain barrier (BBB) and the cerebral inflammatory response occurring after traumatic brain injury (TBI) facilitate further brain damage, which leads to long-term complications of TBI. Fibroblast growth factor 20 (FGF20), a neurotrophic factor, plays important roles in brain development and neuronal homeostasis. The aim of the current study was to assess the protective effects of FGF20 on TBI via BBB maintenance. In the present study, recombinant human FGF20 (rhFGF20) reduced neurofunctional deficits, brain edema, Evans blue extravasation and neuroinflammation in a TBI mouse model. In anin vitroTNF-α-induced human brain microvascular endothelial cell (HBMEC) model of BBB disruption, rhFGF20 reduced paracellular permeability and increased trans-endothelial electrical resistance (TEER). Both in the TBI mouse model andin vitro, rhFGF20 increased the expression of proteins composing in BBB-associated tight junctions (TJs) and adherens junctions (AJs), and decreased the inflammatory response, which protected the BBB integrity. Notably, rhFGF20 preserved BBB function by activating the AKT/GSK3β pathway and inhibited the inflammatory response by regulating the JNK/NFκB pathway. Thus, FGF20 is a potential candidate treatment for TBI that protects the BBB by upregulating junction protein expression and inhibiting the inflammatory response.

How neuromodulatory transmitters diffuse into the extracellular space remains an unsolved fundamental biological question, despite wide acceptance of the volume transmission model. Here, we report development of a method combining genetically encoded fluorescent sensors with high-resolution imaging and analysis algorithms which permits the first direct visualization of neuromodulatory transmitter diffusion at various neuronal and non-neuronal cells. Our analysis reveals that acetylcholine and monoamines diffuse at individual release sites with a spread length constant of ∼0.75 μm. These transmitters employ varied numbers of release sites, and when spatially close-packed release sites coactivate they can spillover into larger subcellular areas. Our data indicate spatially restricted (i.e., nonvolume) neuromodulatory transmission to be a prominent intercellular communication mode, reshaping current thinking of control and precision of neuromodulation crucial for understanding behaviors and diseases.

Scattered radiation unavoidably generated in the patient will negatively impact both kilovoltage (KV) and megavoltage (MV) imaging applications. Recently, 'hybrid' methods (i.e. combining analytical and Monte Carlo (MC) techniques) are being investigated as a solution to accurately yet quickly calculate the scattered contribution for both KV and MV images. We have developed a customized MC simulation user code for investigating the individual components of patient-scattered photon fluence, which serves as a valuable tool in this area of research. The MC tool is based on the EGSnrc/DOSXYZnrc user code. The IAUSFL flag options associated with subroutine AUSGAB, combined with LATCH tracking, are used to classify the various interactions of particles with the media. Photons are grouped into six different categories: primary, 1st Compton scatter, 1st Rayleigh scatter, multiple scatter, bremsstrahlung, and positron annihilation. We take advantage of the geometric boundary check in DOSXYZnrc, to write exiting photon particle information to a phase-space file. The tool is validated using homogeneous and heterogeneous phantom configurations with monoenergetic and polyenergetic beams under parallel and divergent beam geometry, comparing MC-simulated exit primary fluence and singly-scattered fluence to corresponding analytical calculations. This MC tool has been validated to separately score the primary and scatter fluence components of the KV and MV imaging applications in the field of radiation therapy. The results are acceptable for the various configurations and beam energies tested here. Overall, the mean percentage differences are less than 0.2% and standard deviations less than 1.6%. This will be a critical test instrument for research in photon scatter applications and particularly for the development of hybrid methods, and is freely available from the authors for research purposes.5.

Here we design and optimize a genetically encoded fluorescent indicator, iAChSnFR, for the ubiquitous neurotransmitter acetylcholine, based on a bacterial periplasmic binding protein. iAChSnFR shows large fluorescence changes, rapid rise and decay kinetics, and insensitivity to most cholinergic drugs. iAChSnFR revealed large transients in a variety of slice and in vivo preparations in mouse, fish, fly and worm. iAChSnFR will be useful for the study of acetylcholine in all animals.

Here we design and optimize a genetically encoded fluorescent indicator, iAChSnFR, for the ubiquitous neurotransmitter acetylcholine, based on a bacterial periplasmic binding protein. iAChSnFR shows large fluorescence changes, rapid rise and decay kinetics, and insensitivity to most cholinergic drugs. iAChSnFR revealed large transients in a variety of slice and in vivo preparations in mouse, fish, fly and worm. iAChSnFR will be useful for the study of acetylcholine in all organisms.

PurposeEconomic theories on structural change focus on factors such as fluctuations in relative prices and income growth. In addition, China’s reform and opening up has also been accompanied by increasing openness, significant fluctuations in investment rates, and frictions in the labor market. Existing literature lacks a unified theoretical framework to assess the relative importance of all these determinants. The paper aims to discuss these issues.Design/methodology/approachTo incorporate all of the potential determinants of China’s structural change, the authors build a two-country four-sector neoclassical growth model that embeds the multi-sector Eaton and Kortum (2002) model of international trade, complete input-output structure, non-homothetic preference and labor market frictions. The authors decompose the sectoral employment shares into six effects: the Baumol, Engel, investment, international trade, factor intensity and labor market friction effects. Using the data of Chinese economy from 1978 to 2011, the authors perform a quantitative investigation of the six determinants’ effects through the decomposition approach and counterfactual exercises.FindingsLow-income elasticity of demand, high labor intensity, and the existence of the switching costs are the reasons for the high employment share in the agricultural sector. Technological progress, investment and international trade have comparatively less influence on the proportion difference of employment in the three sectors.Originality/valueTherefore, to examine the impact on China’s structural change, in addition to Baumol effect and the Engel effect, it is also necessary to consider the impact of three more factors: international trade, investment and switching costs. Therefore, the authors decompose the factors that may influence China’s structural change into the Baumol, Engel, investment, international trade, factor intensity effect and switching cost effects. The authors evaluate these six effects using the decomposition approach and counterfactual exercises.

Background ：Blood-brain barrier (BBB) disruption and the cerebral inflammatory response are two reciprocal mechanisms that work together to mediate the degree of brain edema, which is responsible for the majority of deaths after traumatic brain injury (TBI), and facilitate further brain damage, which leads to long-term TBI complications. Fibroblast growth factor 20 (FGF20), a neurotrophic factor, plays important roles in the development of dopaminergic neurons in Parkinson disease (PD). However, little is known about the role of FGF20 in TBI. The aim of the current study was to assess the protective effects of FGF20 in TBI through protecting the BBB. Methods: We explored the relationship between FGF20 and BBB function in controlled cortical impact (CCI)-induced TBI mice model and TNF-α-induced human brain microvascular endothelial cell (HBMEC) in vitro BBB disruption model. We also explored the mechanisms of these interactions and the signaling processes involved in BBB function and neuroinflammation. Results: In this study, we demonstrate that recombinant human FGF20 (rhFGF20) reduced neurofunctional deficits, brain edema and Evans Blue penetration in vivo after TBI. In an in vitro BBB disruption model of, rhFGF20 could reverse changes to TNF-α-induced HBMEC morphology, reduce Transwell permeability, and increase transendothelial electrical resistance (TEER). In both a TBI mouse model and in vitro , rhFGF20 upregulated the expression of BBB-associated tight junction (TJ) protein and adherens junction (AJ) protein via the AKT/GSK3β pathway. In addition, rhFGF20 inhibited the cerebral inflammatory response through regulating the JNK/NFκB pathway and further protected the function of the BBB. Conclusions : Our results contribute to a new treatment strategy in TBI research. FGF20 is a potential candidate to treat TBI as it protects the BBB via regulating the AKT/GSK3β and JNK/NFκB signaling pathways.

The development of efficient, cost-effective, bifunctional and self-supported electrocatalysts for overall water splitting in a wide pH range is highly desirable. A novel and highly efficient electrocatalyst for overall water splitting in a wide pH range was synthesized via the electroless plating of FeCoNiB alloy nanoparticles on B-doped vertically aligned graphene arrays (FeCoNiB@B-VG). FeCoNiB@B-VG exhibited excellent electrocatalytic performances with a low overpotential of 31 mV in 1.0 M KOH and 148 mV in 0.5 M H2SO4 for hydrogen evolution reaction (HER), and an overpotential of 387 mV in 1.0 M KOH for oxygen evolution reaction (OER). It also exhibited a quite low Tafel slope value of 30 mV dec−1 and 51 mV dec−1 for HER and OER in 1.0 M KOH respectively. In addition, FeCoNiB@B-VG also exhibited good long-term stabilities in acidic and alkaline electrolytes as a self-supported bifunctional electrocatalyst. This work may provide theoretical and technical support for design of cost-effective bifunctional electrocatalysts for overall water splitting in a wide pH range.

This paper focuses on explaining the demographic transition and some of the broad patterns that are associated with it. We present an endogenous growth model that incorporates altruism and son preference within the family as well as gender wage gap and gender wage discrimination in the labour market. We show that with the accumulation of physical capital and human capital, the output share of mental labour increases and the gender wage gap narrows. In the early stages of economic development, gender discrimination is becoming prevalent and the substitution effect of capital accumulation, which raises the cost of child rearing, is dominated by the income effect, so the growth rate of population increases with income. When the degree of gender wage discrimination starts to decline, the increased cost of child rearing induces families to invest more in the human capital of children and the growth rate of the population falls. The quantitative analysis shows that gender wage discrimination is indeed an important contributor to the demographic transition.

Various techniques of deep inspiration breath hold (DIBH) have been used to mitigate the likelihood and risk of exposing the heart, an organ-at-risk (OAR) for unintended radiation during left breast radiotherapy. However, issues of reproducibility of these techniques warrant further investigation into the feasibility of detecting the intrusion of an OAR into the treatment field during intra-fractional treatment delivery. The increase of high-dose, low-fraction radiotherapy treatments makes it important to immediately adapt treatment once an OAR is detected in the treatment field. This proof-of-concept implementation includes an algorithm that detects and tracks the motion at the edges of a treatment field and a control algorithm that adapts the treatment aperture according to the motion detected. In accordance to the AAPM Task-Group (TG-132) report, image registration techniques should be verified with virtual and physical phantoms prior to clinical application. Since most OARs move as a result of respiration-induced motion, we have used a lung phantom to generate images of a generic OAR intruding into a treatment field with known velocity. The phantom was programmed to move with sinusoidal and lung patient tumor motion patterns and the accuracy of intrusion tracking and MLC adaptation were benchmarked with the ground truth-programmed motion of the OAR. The motions were recorded with an electronic portal imaging device (EPID). An optimal cluster size of 9 × 9 motion vectors was found to provide the smallest average absolute position error of 0.3 mm. A strong linear correlation between the adapted MLC leaves and the actual OAR position was observed. The algorithm had a mean position tracking error of -0.4 ± 0.3 mm and a precision of 1.1 mm. It is possible to adapt MLC leaves based on the motion detected at the edges of the irradiated field, and it would be feasible to shield an unplanned intrusion of an OAR into the treatment field.

Wound healing, especially for diabetic wounds, is a lengthy and complicated process involving interactions and responses at the protein, cell, and tissue levels. Loading of growth factors into a hydrogel to construct a sustained-release system is considered a promising approach to improve wound healing. The present study investigates the effect of thermosensitive heparin-poloxamer (HP) hydrogel-encapsulated recombinant human fibroblast growth factor 21 (rhFGF21) on wound healing in mice with streptozotocin-induced diabetes mellitus. First, we studied the in vitro release of rhFGF21 from the rhFGF21-HP coacervate. The results showed that HP might control the release of rhFGF21. Next, we examined the effect of rhFGF21-HP on skin wound healing in diabetic mice. Our data showed that rhFGF21-HP significantly improved wound closure; promoted granulation, collagen deposition, and re-epithelialization; and enhanced the expression of CD31. Moreover, rhFGF21-HP had obvious advantages in diabetic wound healing. Therefore, the results suggest that the rhFGF21-HP hydrogel polymer plays an important role in skin wound healing. This work provides a suitable sustained-release delivery system that can continuously release rhFGF21 and presents a promising therapeutic strategy for wound healing in patients with diabetes.-Liu, H., Zhao, Y., Zou, Y., Huang, W., Zhu, L., Liu, F., Wang, D., Guo, K., Hu, J., Chen, J., Ye, L., Li, X., Lin, L. Heparin-poloxamer hydrogel-encapsulated rhFGF21 enhances wound healing in diabetic mice.

Perinatal asphyxia often results in neonatal cerebral hypoxia-ischemia (HI), which is associated with high mortality and severe long-term neurological deficits in newborns. Currently, there are no effective drugs to mitigate the functional impairments post-HI. Previous studies have shown that fibroblast growth factor 21 (FGF21) has a potential neuroprotective effect against brain injury. However, the effect of FGF21 on neonatal HI brain injury is unclear. In the present study, both in vivo and in vitro models were used to assess whether recombinant human FGF21 (rhFGF21) could exert a neuroprotective effect after HI and explore the associated mechanism. The results showed that the rhFGF21 treatment remarkably reduced the infarct volume, ameliorated the body weight and improved the tissue structure after HI in neonatal rats. In addition, the rhFGF21 treatment lengthened the running endurance times in the rotarod test and decreased the mean escape latencies and increased the number of platform crossings in the Morris water maze test at 21 d post-HI insult. In contrast, the FGFR1 inhibitor PD173074 and PI3K inhibitor LY294002 partially reversed these therapeutic effects. In isolated primary cortical neurons, the rhFGF21 treatment protected primary neurons from oxygen-glucose deprivation (OGD) insult by inhibiting neuronal apoptosis and promoting neuronal survival. Both our in vivo and in vitro results reveal that rhFGF21 could inhibit neuronal apoptosis by activating the PI3K/Akt signaling pathway via FGF21/FGFR1/β-klotho complex formation. Therefore, rhFGF21 may be a promising therapeutic agent for promoting functional recovery after HI-induced neonatal brain injury.

In vivo dosimetry methods can verify the prescription dose is delivered to the patient during treatment. Unfortunately, in exit dosimetry, the megavoltage image is contaminated with patient-generated scattered photons. However, estimation and removal of the effect of this fluence improves accuracy of in vivo dosimetry methods. This work develops a 'tri-hybrid' algorithm combining analytical, Monte Carlo (MC) and pencil-beam scatter kernel methods to provide accurate estimates of the total patient-generated scattered photon fluence entering the MV imager. For the multiply-scattered photon fluence, a modified MC simulation method was applied, using only a few histories. From each second- and higher-order interaction site in the simulation, energy fluence entering all pixels of the imager was calculated using analytical methods. For photon fluence generated by electron interactions in the patient (i.e. bremsstrahlung and positron annihilation), a convolution/superposition approach was employed using pencil-beam scatter fluence kernels as a function of patient thickness and air gap distance, superposed on the incident fluence distribution. The total patient-scattered photon fluence entering the imager was compared with a corresponding full MC simulation (EGSnrc) for several test cases. These included three geometric phantoms (water, half-water/half-lung, computed tomography thorax) using monoenergetic (1.5, 5.5 and 12.5 MeV) and polyenergetic (6 and 18 MV) photon beams, 10 × 10 cm2 field, source-to-surface distance 100 cm, source-to-imager distance 150 cm and 40 × 40 cm2 imager. The proposed tri-hybrid method is demonstrated to agree well with full MC simulation, with the average fluence differences and standard deviations found to be within 0.5% and 1%, respectively, for test cases examined here. The method, as implemented here with a single CPU (non-parallelized), takes ∼80 s, which is considerably shorter compared to full MC simulation (∼30 h). This is a promising method for fast yet accurate calculation of patient-scattered fluence at the imaging plane for in vivo dosimetry applications.

Structural transformation is a key feature of economic development. Traditional literature attributes it to changes in the sectoral composition of consumption. Different from it, we argue that the "servici fication" of investment goods, which is induced by investment-specific technological change, becomes an increasingly important reason for structural transformation, particularly for the rise of the services economy. Our study of the input output tables finds that the share of service inputs in investment goods have grown significantly in many countries since the 1980s, especially for investment-intensive economies such as China. To assess if the investment channel is quantitatively significant, we build a standard model with three broad sectors, but instead add an investment production function employing factors from all three sectors. Moreover, we incorporate investment-specific technological change by allowing the productivities of the three sectoral inputs to evolve over time. We calibrate the model to the Chinese economy from 1981-2014 and perform counter-factual experiments accordingly. We find that the technological change in the investment sector accounts for 33.1 percent decline in employment share of agriculture, 36.0 percent increase in employment share of manufacturing and 31.5 percent increase in employment share of services over the period. The magnitude of this effect on the share of services keeps growing, particularly after 2000. Our findings are not unique for China, but also apply to other economies experiencing "servici fication" of investment sector.

We analyze sunspots rotation and magnetic transients in NOAA AR 11429 during two X-class (X5.4 and X1.3) flares using the data from the Helioseismic and Magnetic Imager on board the \emph{Solar Dynamics Observatory}. A large leading sunspot with positive magnetic polarity rotated counterclockwise. As expected, the rotation was significantly affected by the two flares. The magnetic transients induced by the flares were clearly evident in the sunspots with negative polarity. They were moving across the sunspots with speed of order $3-7\ \rm km \ s^{-1}$. Furthermore, the trend of magnetic flux evolution of these sunspots exhibited changes associated with the flares. These results may shed light on the understanding of the evolution of sunspots., Comment: Accepted for publication in RAA, 13 pages, 7 figures

Thermal treatment of the substituted tetramethylcyclopentadienes [C5Me4HR] [R = n-propyl (1), i-propyl (2), cyclopentyl (3), cyclohexyl (4), and 4-NMe2Ph (5)] with Fe(CO)5 gave five new substituted tetramethylcyclopentadienyl dinuclear iron carbonyl complexes, [η5-C5Me4CH2CH2CH3]2Fe2(CO)4 (6), [η5-C5Me4CH(CH3)2]2Fe2(CO)4 (7), [η5-C5Me4CH(CH2)4]2Fe2(CO)4 (8), [η5-C5Me4CH(CH2)5]2Fe2(CO)4 (9), and [(η5-C5Me4)(4-NMe2Ph)]2Fe2(CO)4 (10). The new complexes were characterized by elemental analysis, IR, and 1H NMR spectra. The molecular structures of 6, 8, 9, and 10 were determined by X-ray single crystal diffraction.

The reactions of the substituted tetramethylcyclopentadienes [C5Me4HR] [R = ethyl (1), n-propyl (2), i-propyl (3), cyclopentyl (4), cyclohexyl (5), 4-NMe2Ph (6)] with Mo(CO)6 in refluxing xylene gave the corresponding dinuclear metal carbonyl complexes [η5-C5Me4R]2Mo2(CO)6 (7–11), while similar treatment of [C5Me4H(4-NMe2Ph)] (6) with Mo(CO)6 afforded an unexpected product [(η5-C5Me4(4-NMe2Ph))MoO2]2(μ-O) (12). All the new complexes were fully characterized. The molecular structures of 7, 8, 11 and 12 have been determined by X-ray single crystal diffraction.

A mechanical counter-steering prototype which includes a mechanical slider system was developed to evaluate tracking and prediction algorithms used for tumor motion compensation. The compensation aims to maintain a stationary tumor with respect to the radiation beam. Motion tracking was performed with an optical flow algorithm. Three techniques of reference image registration were evaluated. To compensate for system latency, a neural network with a sliding window learning scheme was used to predict the tumor positon. A mean tracking (position) error of −0.05 ± 0.04 mm was obtained using initial image for reference registration. For our prediction module, an averaged mean error and mean absolute error (MAE) of 0.07±0.96 mm and 0.61 ± 0.80 were obtained for seven patients respectively. When incorporating tracking and prediction an averaged mean error of 0.30 ± 1.06 mm and a MAE of 0.8 ± 0.76 mm were observed. Results show that this image-guided prototype is suited for evaluating the tracking and prediction modules of a motion compensating radiotherapy system.

Reactions of thienyl side-chain-functionalized cyclopentadienyl ligands C5H5C(R1R2)C4H3S [R1 = R2 = CH3 (1); R1 = CH3, R2 = C2H5 (2); R1 = R2 = C2H5 (3); R1, R2 = (CH2)5 (4)] with Mo(CO)6 in refluxing xylene gave the corresponding cyclopentadienyl dimolybdenum carbonyl complexes: [(η5-C5H4)C(R1R2) × (C4H3S)Mo(CO)3]2 [R1 = R2 = CH3 (5); R1 = CH3, R2 = C2H5 (6); R1 = R2 = C2H5 (7); R1, R2 = (CH2)5 (8)]. They are characterized by elemental analysis, IR and 1H NMR spectra. The molecular structures of (5) and (8) are determined by single crystal X-ray diffraction.

This work compares three methods of tracking lung tumor motion using an optical flow algorithm to analyze portal images. An earlier approach used sequential image pairs (CU) to track the motion. Errors in the position of the tumor were found to accumulate when patient traces were used and two new approaches were introduced. The first method re-calibrates the position of the tumor at the end-ofexhale (EoE) of each breathing cycle. This was done by computing the position directly between the new image and the previous reference image. The new image at the EoE is then assigned as the new reference frame, a process called reference shifting (RFSF). Between two EoE, sequential tracking was employed. The second approach derives the position of the tumor in each frame by applying the optical flow computation directly between each image and a reference image. However, since tracking is limited to a finite range (i.e. threshold), new reference images were required when the tumor exceeds a set distance from the reference position, a process called threshold shifting (THSF). Direct comparison of the position in subsequent images was made with respect to the new reference image. A 3D tumor prototype was fabricated using 3D printing techniques and seven patient traces were evaluated. Average position errors of -0.01 ± 0.65 mm, -0.10 ± 0.42 mm and -0.14 ± 0.25 were obtained for the CU, RFSF and THSF methods respectively.

Purpose: This work reports on the development of a mechanical slider system for the counter-steering of tumor motion in adaptive Radiation Therapy (RT). The tumor motion was tracked using a weighted optical flow algorithm and its position is being predicted with a neural network (NN). Methods: The components of the proposed mechanical counter-steering system includes: (1) an actuator which provides the tumor motion, (2) the motion detection using an optical flow algorithm, (3) motion prediction using a neural network, (4) a control module and (5) a mechanical slider to counter-steer the anticipated motion of the tumor phantom. An asymmetrical cosine function and five patient traces (P1–P5) were used to evaluate the tracking of a 3D printed lung tumor. In the proposed mechanical counter-steering system, both actuator (Zaber NA14D60) and slider (Zaber A-BLQ0070-E01) were programed to move independently with LabVIEW and their positions were recorded by 2 potentiometers (ETI LCP12S-25). The accuracy of this counter-steering system is given by the difference between the two potentiometers. Results: The inherent accuracy of the system, measured using the cosine function, is −0.15 ± 0.06 mm. While the errors when tracking and prediction were included, is (0.04 ± 0.71) mm. Conclusion: A prototype tumor motion counter-steering system with tracking and prediction was implemented. The inherent errors are small in comparison to the tracking and prediction errors, which in turn are small in comparison to the magnitude of tumor motion. The results show that this system is suited for evaluating RT tracking and prediction.