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The compaction behavior of continuous carbon fiber tows was experimentally studied by means of laser light sectioning method. This method allows a direct measurement of tow cross-sectional dimensions during continuous processes. In this work the carbon fiber tows are axially stressed and laid on a curved structure in order to examine their compaction behavior on a smooth surface. The results show a similar compaction behavior for all studied carbon fiber tows that is independent of the tow size.

Summary Lipid composition affects the biophysical properties of membranes that provide a platform for receptor-mediated cellular signaling. To study the regulatory role of membrane lipid composition, we combined genetic perturbations of sphingolipid metabolism with the quantification of diverse steps in Toll-like receptor (TLR) signaling and mass spectrometry-based lipidomics. Membrane lipid composition was broadly affected by these perturbations, revealing a circular network of coregulated sphingolipids and glycerophospholipids. This evolutionarily conserved network architecture simultaneously reflected membrane lipid metabolism, subcellular localization, and adaptation mechanisms. Integration of the diverse TLR-induced inflammatory phenotypes with changes in lipid abundance assigned distinct functional roles to individual lipid species organized across the network. This functional annotation accurately predicted the inflammatory response of cells derived from patients suffering from lipid storage disorders, based solely on their altered membrane lipid composition. The analytical strategy described here empowers the understanding of higher-level organization of membrane lipid function in diverse biological systems., Graphical Abstract, Highlights • Coregulation between membrane lipid species is organized in a circular network • The lipid network is conserved and reflects metabolism, localization, and adaptation • Sphingolipid metabolism regulates TLR trafficking, signaling, and cytokine release • Network-wide functional lipid annotations predict TLR responses in patient cells, Combining lipidomics with genetic perturbations in immune cells reveals the logic of inter-lipid regulatory structure and enables the functional assignment of lipids to different steps of Toll-like receptor signaling. Moreover, quantitative lipidomics alone can predict the inflammatory response of patient-derived cells.

Liquid composite molding (LCM) techniques are innovative manufacturing processes for processing fiber reinforced polymer parts used e.g. for aerospace structures. Thereby the reinforcing material is placed in a mold and infiltrated with a low viscosity polymer matrix. Increasing production rates as well as part complexity lead to high production risks such as air inclusions or incomplete mold filling. Numerical mold filling simulations are promising tools enabling the composite manufacturing engineer to detect dry spots in the mold and find the optimal positions of the resin entry and ventilation system at an early process development stage. Today, different numerical models and software packages are available for modeling the flow through the reinforcing structure for visualization of the flow behavior. The goal of this study is the systematic comparison of two different software packages, namely PAM-RTM® and OpenFOAM. Both software tools are operated as they are commonly foreseen. Real world experiments under real process conditions are the basis for the assessment of the numerical predictions. The resin transfer molding (RTM) experiments are executed in a tool with a transparent upper mold half in order to see the flow front advancement. POLYM. COMPOS., 2015. © 2015 Society of Plastics Engineers

Material parameters such as the permeability of dry reinforcing textiles are key variables for modern composite production using liquid composite molding (LCM) technique. Nowadays numerical filling simulations are required for predicting the mold filling behavior. Inaccurate predictions can lead to a high risk of air inclusion and corresponding need for cost-intense revision of the mold design. Permeability values of the textiles used in the process are basic requirements for a numerical filling simulation, since the permeability is directly linked to the filling behavior. Nevertheless, the permeability values of non-crimped fabrics (NCF) which are used for aerospace and automotive structures are rare. In this study the influence of textile parameters of NCF on the in-plane permeability has been investigated using a capacitive in-plane permeability measurement technology. The results show the influence of the roving filament number as well as the used stitch length on the in-plane permeability. It is confirmed that the textile grammage is not affecting the in-plane permeability of NCF reinforcements. The results of this study are valuable for textile selection with specific permeability data as well as for numerical filling simulations. POLYM. COMPOS., 2015. © 2015 Society of Plastics Engineers

Cell growth and proliferation are tightly linked to nutrient availability. The mechanistic target of rapamycin complex 1 (mTORC1) integrates the presence of growth factors, energy levels, glucose and amino acids to modulate metabolic status and cellular responses1-3. mTORC1 is activated at the surface of lysosomes by the RAG GTPases and the Ragulator complex through a not fully understood mechanism monitoring amino acid availability in the lysosomal lumen and involving the vacuolar H+ -ATPase 4-8. Here we describe the uncharacterized human member 9 of the solute carrier family 38 (SLC38A9) as a lysosomal membrane-resident protein competent in amino acid transport. Extensive functional proteomic analysis established SLC38A9 as an integral part of the Ragulator/RAG GTPases machinery. Gain of SLC38A9 function rendered cells resistant to amino acid withdrawal, while loss of SLC38A9 expression impaired amino acid-induced mTORC1 activation. Thus SLC38A9 is a physical and functional component of the amino acid-sensing machinery that controls the activation of mTOR.

Global debates on social protection have raised concerns about the appropriateness of the targeting approach for better inclusion. This study contributes to these debates by exploring the specific challenges associated with the targeting mechanism adopted by the Ghana Livelihood Empowerment against Poverty (LEAP) programme within the Upper West Regional programme district of Wa Municipality of Ghana. Qualitative data on beneficiaries’ perceptions and experiences with the LEAP programme were collected through in-depth interviews with 30 LEAP beneficiaries and key informant interviews with three LEAP implementers. The findings reveal widespread perceptions of inclusion errors associated with the targeting approach adopted by LEAP. These perceived inclusion errors are as a result of lack of transparency in the handling of procedures, political interference in the selection process and poor data on household’s poverty statuses. Unintended consequences of the approach include poverty-labeling, stigmatization and envy of beneficiaries leading to hatred and conflicts which are capable of destroying social cohesion in rural beneficiary communities. A sense of beneficiary powerlessness to question the ‘ills’ in the operations of programme is also a challenge inherent in the targeting approach. To ensure effective targeting, there is the need for education to be provided on the purpose, selection process and benefits of the programme, particularly, at the community level. There is also the need to strengthen the monitoring of the selection process. It is important that civil society organizations provide complementary interventions to empower beneficiaries to demand for their entitlements from the programme. Keywords : Social Protection, Cash Transfers, Targeting Approach, Challenges, Livelihood Empowerment against Poverty, Ghana

Dalam perkembangan industri di era modern menuntut perusahaan manufaktur untuk meningkatkan kualitas dari produk yang dihasilkan. Semakin tinggi kualitas produk yang dihasilkan akan semakin tinggi pula nilai jual produk. Salah satu mesin manufaktur yang menghasilkan produk dengan tingkat akurasi tinggi, handal, dan keterulangan yang baik yaitu mesin CNC. Kualitas dari produk mesin konvensional dipengaruhi oleh beberapa faktor diantaranya, pengendalian motor penggerak yang kurang presisi, tingkat ketelitian operator yang terbatas, dan sistem pengerjaan yang dilakukan secara manual. Pada penelitian ini dirancang sebuah mesin CNC router dan dilakukan pengujian pemotongan dengan menggunakan material kayu. Hasil percobaan menunjukkan rangkaian CNC memiliki ketelitian sangat bagus yang dinyatakan melalui standar deviasi sebesar 0,025 mm. Hasil ini menunjukkan standar deviasi lebih baik dari penelitian sebelumnya.

The electronic structure of Mg and free-base tetraphenylporphyrin films on Ag(100) is investigated by one- and two-photon photoemission in combination with electronic structure calculations using density functional theory and the self-consistent $G{W}_{0}$ method. We determine the two highest occupied and the nearly degenerate lowest unoccupied molecular orbitals. Higher unoccupied states are seen in an enhanced emission as a final-state effect. For photon energies close to the prominent absorption of the Soret band we observe a strong electron emission attributed to the break up of the bound electron-hole pairs in the ${S}_{2}$ excited state. The experimental results on the occupied and unoccupied energy levels for the molecular films on Ag(100) nicely agree with calculated quasiparticle energies and experiments of the molecules in the gas phase.

Using x-ray photoemission spectroscopy, we investigated the self-metalation of free-base tetraphenylporphyrin (2HTPP) on thin MgO(100) films on Ag(100). The deposition of one monolayer 2HTPP on MgO results in the formation of magnesium(ii) tetraphenylporphyrin (MgTPP) at room temperature. We demonstrate that the efficiency of the reaction drastically depends on the morphology of the oxide layers. The latter is changed by varying the substrate temperature during the oxide growth. We observe the complete metalation of the 2HTPP monolayer when the MgO films are grown at 393 K. The increase of the growth temperature to 573 K leads to the reduction of the percentage of metalated molecules to ∼50%. We ascribe these results to the fact that MgTPP formation takes place through the hydroxilation of steps and defects on the MgO surface, which leads to an increase of the OH component in the O 1s line.

We measure temperature-dependent one-photon and two-photon induced photoluminescence from (${\mathrm{CH}}_{3}{\mathrm{NH}}_{3}$)${\mathrm{PbBr}}_{3}$ single crystals cleaved in ultrahigh vacuum. An approach is presented to extract absorption spectra from a comparison of both measurements. Cleaved crystals exhibit broad photoluminescence spectra. We identify the direct optical band gap of 2.31 eV. Below 200 K, the band gap increases with temperature, and it decreases at elevated temperature, as described by the Bose-Einstein model. An excitonic transition is found 22 meV below the band gap at temperatures $l200$ K. Defect emission occurs at photon energies $l2.16$ eV. In addition, we observe a transition at 2.25 eV (2.22 eV) in the orthorhombic (tetragonal and cubic) phase. Below 200 K, the associated exciton binding energy is also 22 meV, and the transition redshifts at higher temperature. The binding energy of the exciton related to the direct band gap, in contrast, decreases in the cubic phase. High-energy emission from free carriers is observed with higher intensity than reported in earlier studies. It disappears after exposing the crystals to air.

Long carrier lifetimes and diffusion lengths form the basis for the successful application of the organic-inorganic perovskite (CH$_3$NH$_3$)PbI$_3$ in solar cells and lasers. The mechanism behind the long carrier lifetimes is still not completely understood. Spin-split bands and a resulting indirect band gap have been proposed by theory. Using near band-gap left-handed and right-handed circularly polarized light we induce photocurrents of opposite directions in a single-crystal (CH$_3$NH$_3$)PbI$_3$ device at low temperature ($4~\mathrm{K}$). The phenomenom is known as the circular photogalvanic effect and gives direct evidence for phototransport in spin-split bands. Simultaneous photoluminecence measurements show that the onset of the photocurrent is below the optical band gap. The results prove that an indirect band gap exists in (CH$_3$NH$_3$)PbI$_3$ with broken inversion symmetry as a result of spin-splittings in the band structure. This information is essential for understanding the photophysical properties of organic-inorganic perovskites and finding lead-free alternatives. Furthermore, the optically driven spin currents in (CH$_3$NH$_3$)PbI$_3$ make it a candidate material for spintronics applications.

The topological insulators Bi2Se3 and Bi2Te2Se have been shown to possess unoccupied topological surface states at the center of the surface Brillouin zone at energies around 1.3 eV above the Fermi level. Using time-resolved two-photon photoemission we study the electron dynamics of the unoccupied topological surface states, image-potential states and conduction bands on these surfaces., The present work was partially supported by RFBR (Grant Nos. 12-02-00226 and 13-02-12110).

Composites manufacturing is characterized by many degrees of freedom. Different materials, geometries and thermo-dynamical conditions contribute to a behavior that is difficult to predict. Monitoring the running process (in-line monitoring) eliminates the need for prediction; real time data provided by appropriate sensing systems can be used in the direction of process optimization, quality upgrade or material characterization. The aim of the review at hand is to record and discuss the latest progress in the field of in-line composites monitoring with a focus on Fiber Reinforced Polymeric- based (FRP) composite structures. Summaries of each sensor's principles of operation, appropriate association with poly- mer/composite properties detection, brief descriptions of representative studies, a critical overview of implementation aspects and discussion on the upcoming trends, contribute in constructing a complete picture.