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We present the first catalog of very-high energy and ultra-high energy $\gamma$-ray sources detected by the Large High Altitude Air Shower Observatory (LHAASO), using 508 days of data collected by the Water Cherenkov Detector Array (WCDA) from March 2021 to September 2022 and 933 days of data recorded by the Kilometer Squared Array (KM2A) from January 2020 to September 2022. This catalog represents the most sensitive $E > 1$ TeV gamma-ray survey of the sky covering declination from $-$20$^{\circ}$ to 80$^{\circ}$. In total, the catalog contains 90 sources with extended size smaller than $2^\circ$ and with significance of detection at $> 5\sigma$. For each source, we provide its position, extension and spectral characteristics. Furthermore, based on our source association criteria, 32 new TeV sources are proposed in this study. Additionally, 43 sources are detected with ultra-high energy ($E > 100$ TeV) emission at $> 4\sigma$ significance level., Comment: 35 pages, 10 figures, 3 tables

We thank Arnbjerg-Nielsen and co-authors for their constructive contribution. We endorse their key comments and suggestions on how to increase awareness of and action on water quality interactions in the water–energy–food (WEF) nexus. Here, we advance the discussion, commenting on the scope of water quality to embrace ecosystem as well as human needs, and the importance of transdisciplinarity and focusing at the city/aquifer/drainage basin scale in WEF nexus hotspots in ensuring that water quality is considered in WEF nexus approaches. We also identify how recent global events, the COVID-19 pandemic and the 26th Conference of the Parties to the UN Framework Convention on Climate Change (UNFCCC COP 26), may intensify the WEF nexus and its water quality interlinkages, highlighting the need to weave WEF considerations into addressing the United Nations Sustainable Development Goals and the climate and biodiversity emergencies.

The Large High Altitude Air Shower Observatory (LHAASO) has three sub-arrays, KM2A, WCDA and WFCTA. The flux variations of cosmic ray air showers were studied by analyzing the KM2A data during the thunderstorm on 10 June 2021. The number of shower events that meet the trigger conditions increases significantly in atmospheric electric fields, with maximum fractional increase of 20%. The variations of trigger rates (increases or decreases) are found to be strongly dependent on the primary zenith angle. The flux of secondary particles increases significantly, following a similar trend with that of the shower events. To better understand the observed behavior, Monte Carlo simulations are performed with CORSIKA and G4KM2A (a code based on GEANT4). We find that the experimental data (in saturated negative fields) are in good agreement with simulations, assuming the presence of a uniform upward electric field of 700 V/cm with a thickness of 1500 m in the atmosphere above the observation level. Due to the acceleration/deceleration and deflection by the atmospheric electric field, the number of secondary particles with energy above the detector threshold is modified, resulting in the changes in shower detection rate., Comment: 18 pages, 11 figures

The Crab pulsar and the surrounding nebula powered by the pulsar's rotational energy through the formation and termination of a relativistic electron-positron wind is a bright source of gamma-rays carrying crucial information about this complex conglomerate. We report the detection of $\gamma$-rays with a spectrum showing gradual steepening over three energy decades, from $5\times 10^{-4}$ to $1.1$ petaelectronvolt (PeV). The ultra-high-energy photons exhibit the presence of a PeV electron accelerator (a pevatron) with an acceleration rate exceeding 15% of the absolute theoretical limit. Assuming that unpulsed $\gamma$-rays are produced at the termination of the pulsar's wind, we constrain the pevatron's size, between $0.025$ and $0.1$ pc, and the magnetic field $\approx 110 \mu$G. The production rate of PeV electrons, $2.5 \times 10^{36}$ erg $\rm s^{-1}$, constitutes 0.5% of the pulsar's spin-down luminosity, although we do not exclude a non-negligible contribution of PeV protons to the production of the highest energy $\gamma$-rays., Comment: 43 pages, 13 figures, 2 tables; Published in Science

38th European Photovoltaic Solar Energy Conference and Exhibition; 622-626, Thermomechanical loads constitute an important stressor affecting the durability of photovoltaic (PV) modules. Because materials with very different coefficient of thermal expansion are stacked together at a pre-set pressure and temperature in the module lamination process, typically in the range of 140 to 160 C, stresses are induced in the module assembly after cooldown to room temperature. The purpose of our study was to understand the potential of a lower lamination temperature to reduce thermomechanical fatigue of PV modules, including effects both on the solder bond and the interconnect ribbons. This was done for two different encapsulants, EVA and POE. For this purpose, a three-dimensional FEM model was applied, using a temperature profile that accounted both for lamination and accelerated thermal cycling according to the IEC 61215 standard. With respect to thermomechanical fatigue, results show that a reduced lamination temperature lowers the subsequent thermomechanical stresses experienced both in the interconnect ribbons and the solder joint. Because degradation by means of thermomechanical fatigue of the cell interconnects is typically found among the main degradation modes in photovoltaic modules, our study concludes that a reduced lamination temperature has potential to extend the module lifetime in the field.

As a sub-array of the Large High Altitude Air Shower Observatory (LHAASO), KM2A is mainly designed to cover a large fraction of the northern sky to hunt for gamma-ray sources at energies above 10 TeV. Even though the detector construction is still underway, a half of the KM2A array has been operating stably since the end of 2019. In this paper, we present the pipeline of KM2A data analysis and the first observation on the Crab Nebula, a standard candle in very high energy gamma-ray astronomy. We detect gamma-ray signals from the Crab Nebula in both energy ranges of 10$-$100 TeV and $>$100 TeV with high significance, by analyzing the KM2A data of 136 live days between December 2019 and May 2020. With the observations, we test the detector performance including angular resolution, pointing accuracy and cosmic ray background rejection power. The energy spectrum of the Crab Nebula in the energy range 10-250 TeV fits well with a single power-law function dN/dE =(1.13$\pm$0.05$_{stat}$$\pm$0.08$_{sys}$)$\times$10$^{-14}$$\cdot$(E/20TeV)$^{-3.09\pm0.06_{stat}\pm0.02_{sys}}$ cm$^{-2}$ s$^{-1}$ TeV$^{-1}$. It is consistent with previous measurements by other experiments. This opens a new window of gamma-ray astronomy above 0.1 PeV through which ultrahigh-energy gamma-ray new phenomena, such as cosmic PeVatrons, might be discovered., 13 pages, 15 figures,submitted to CPC

37th European Photovoltaic Solar Energy Conference and Exhibition; 848-852, The purpose of this study was to compare thermomechanical fatigue of glass-glass modules to glass-foil modules, including effects both on the solder bond and the interconnect ribbon. A comparison between glass-glass modules based on POE and EVA as encapsulants were also conducted. A 3D FEM-based model was used to study the fatigue damage to photovoltaic modules exposed to thermal cycling according to the IEC 61215 standard. With respect to thermomechanical fatigue of the interconnect ribbons, model results show that a glass-glass module is more robust than a glass-foil assembly with the same front glass thickness. In the coming years the market share of POE is expected to increase at the cost of EVA, and computed results show that a glass-glass module with POE as encapsulant is more robust with respect to this type of fatigue than EVA. Similar considerations for the solder layer connecting the busbar to the ribbon conclude that there is larger plastic work and damage both for a glass-foil assembly (POE) and a glassglass module (EVA) than a glass-glass assembly based on POE as encapsulant. We conclude that such studies must account for a full-size PV module including fixation and the initial lamination process.

36th European Photovoltaic Solar Energy Conference and Exhibition; 1069-1072, Acetic acid is produced in solar modules encapsulated with an Ethylene Vinyl Acetate based polymer. This is a major issue for the long-term stability of the module performance (i.e. series resistance increase and fill factor reduction). Quantitative assessment of acetic acid generation is necessary for the development of durability models. This step requires the use of invasive techniques, which ultimately destroy the module. In this work, a facile solution to opening modules for measurement of acid concentration is tested. An ETFE foil is placed in between the front/rear glass. It is then straightforward to separate the polymer encapsulant from the laminated stack and collect the produced acid. Liquid Chromatography coupled with a UV detector is the technique used to quantify the acetic acid concentration. The effect of the ETFE foil with respect to a standard module configuration (using one-cell mini-modules) during damp heat test is also assessed in order to understand the viability of the proposed method. Results show a faster degradation during damp heat test when ETFE is present due to faster water diffusion and condensation inside the module, an observation that forces us to be cautious on the validity of the results for samples that do not contain ETFE Finally, a preliminary acetic acid production simulation is shown and compared with the obtained experimental results.

In this paper, the torque production mechanisms of flux-reversal permanent magnet (FRPM) machine and Vernier permanent magnet (PM) machine are analyzed and compared based on air-gap field modulation. Working harmonics of PM magnetomotive force (MMF) and air-gap permeance in two machines are analytically identified and compared, indicating that the fundamental PM MMF together with all permeance harmonics contribute to the torque production of Vernier machine whereas all PM MMF harmonics but only fundamental permeance in FRPM machine produces the torque. Thanks to the utilized large dc component of air-gap permeance, the torque density of Vernier machine is revealed to be better. Influence of critical parameters on machine performance, such as PM thickness and slot width ratio of the modulation pole, is also investigated. It shows that FRPM machine is more sensitive to the design parameters. Both finite-element analysis and experimental validation are conducted to verify the conclusion.

The use of kinase-directed precision medicine has been heavily pursued since the discovery and development of\ud imatinib. Annually, it is estimated that around ∼20 000 new cases of tropomyosin receptor kinase (TRK) cancers are diagnosed,\ud with the majority of cases exhibiting a TRK genomic rearrangement. In this Perspective, we discuss current development and\ud clinical applications for TRK precision medicine by providing the following: (1) the biological background and significance of\ud the TRK kinase family, (2) a compilation of known TRK inhibitors and analysis of their cocrystal structures, (3) an overview of\ud TRK clinical trials, and (4) future perspectives for drug discovery and development of TRK inhibitors.

32nd European Photovoltaic Solar Energy Conference and Exhibition; 2265-2269, In 2015 we presented a new measurement method and setup for in-situ moisture ingress monitoring of PV modules for laboratory and field testing applications. The method which is based on miniature digital temperature and humidity sensors was successfully applied to different PV-like stacks with EVA encapsulants. In this work we present the test results of the experiment with sensors laminated in EVA, TPO, POE and Ionomer encapsulants. All samples were exposed to elevated humidity and temperature conditions in a climate chamber. Sensors prove to be robust to the harsh lamination temperature and pressure conditions and produce results that are consistent with the expected moisture ingress properties of the encapsulants. A one-dimensional equivalent electrical simulation model of water diffusion into the encapsulant was developed on the basis of the analogy between the diffusion process and electrical conductivity. The model was implemented in a SPICE simulation program and solved using the transient analysis. The diffusion coefficient of the EVA was obtained as a free fitting parameter and agrees well with the value obtained from an independent DVS experiment, validating our method. Although the experiment lacks the reference diffusion coefficient values of other three tested encapsulants, the fitting results show that the obtained coefficients are in the expected range according to the manufacturers’ specifications.

Multilevel high resistance states are achieved in TiN/HfOx/Pt resistive switching random access memory device by controlling the reset stop voltage. Impedance spectroscopy is used to study the multilevel high resistance states. It is shown that the high resistance states can be described with an equivalent circuit consisting of the major components Rs, R, and C corresponding to the series resistance of the TiON interfacial layer, the equivalent parallel resistance and capacitance of the leakage gap between the TiON layer and the residual conductive filament, respectively. These components show a strong dependence on the stop voltage, which can be explained in the framework of oxygen vacancy model and conductive filament concept. On the other hand, R is observed to decrease with DC bias, which can be attributed to the barrier lowering effect of the Coulombic trap well in the Poole-Frenkel emission model. Accepted version

29th European Photovoltaic Solar Energy Conference and Exhibition; 147-151, Glass-to-Glass (GG) encapsulation scheme and low temperature cell metallization-interconnection technologies known as Smart Wire Connection Technology (SWCT) are promising alternatives to standard design for highly efficient, long lasting photovoltaic modules. The focus of this work was to study the compatibility of different types of encapsulants currently available on the market with these new technologies in terms lamination process and module durability. The feasibility of photovoltaic modules based on GG and SWCT for high-efficiency solar cells is proven using novel laminating lines with which a process cycle time of 4min can be achieved. The results obtained show that thermoplastic polyolefin elastomer (TPO) encapsulants have superior performances compared to other encapsulant types with regards to both the lamination process conditions and the module reliability.

International audience

In this paper, we successfully demonstrate ultrahigh density (>; 10^6 cm^-2) Cu-Cu interconnects of 6-μm pitch using wafer-on-wafer thermo-compression bonding. This is a significant improvement from our previous achievement of 15-μm pitch. In addition, we integrate Cu sealing frame with excellent helium leak rate to the bonded structures to promote the overall bond reliability. On top of that, temporary passivation of Cu surface using self-assembled monolayer (SAM) enhances the resistance against oxidation and particle contamination. Finally, thermal cycling test confirmed the thermal stability of the Cu-Cu daisy chain structure up to 1,000 cycles. Hence, this work opens up new opportunity for wafer level integration of Cu-Cu bonding with state-of-the-art TSV technology, enabling future ultrahigh density 3D IC applications.

25th European Photovoltaic Solar Energy Conference and Exhibition / 5th World Conference on Photovoltaic Energy Conversion, 6-10 September 2010, Valencia, Spain; 4044-4046, Poly (ethylene-co-vinyl acetate) (EVA) is the major polymer used for photovoltaic (PV) modules encapsulation. Its degree of cross-linking (related to its gel content) is taken as a major quality reference. Differential Scanning Calorimetry (DSC) has been proven to be fast and effective but is to determine the gel content, however, destructive for the PV module. With the aim to develop a non-destructive quality assessment tool, a detailed discussion on the DSC thermogram of EVA PV encapsulant is presented here. A possible path towards a fast and non-destructive method for determing EVA gel content is proposed based on the DSC analysis.

The emission spectrum of individual single crystalline ZnO nanowires shows three regimes characterized by distinct polarization properties and spatial emission patterns along the length of the wire. In the visible range below 2.9 eV, emission is polarized along the long axis of the wire, along the c-axis (E//c). In the second regime between 2.9 and 3.22 eV, Fabry-Prot guided modes polarized perpendicular to the wire (Ec) prevail. From their dispersion, it is clear that these modes signify strong coupling between the B-exciton and linearly polarized transverse electric modes that are guided by the wire and trapped between the wire end facets. The third regime is characterized by uniform emission along the wire and a marked dip in the polarization at around the electronic band gap at 3.3 eV. Lasing is observed only in the second regime in which strong light-matter interaction prevails.

We investigate superconductivity and transport properties of Co doped SmFe$_{1-x}$Co$_{x}$AsO system. The antiferromagnetic (AFM) spin-density wave (SDW) order is rapidly suppressed by Co doping, and superconductivity emerges as $x$ $\geq$ 0.05. $T_c$$^{mid}$ increases with increasing Co content, shows a maximum of 17.2 K at the optimally doping of $x\sim$ 0.10. A phase diagram is derived based on the transport measurements and a dome-like $T_c$ versus $x$ curve is established. Meanwhile we found that the normal state thermopower might consist of two different contributions. One contribution increases gradually with increasing $x$, and the other contribution is abnormally enhanced in the superconducting window 0.05 $\leq$ $x$ $\leq$ 0.20, and shows a dome-like doping dependence. A close correlation between $T_{c}$ and the abnormally enhanced term of thermopower is proposed., 5 pages, 5 figures; data added and text revised. A combined version (this paper and arXiv:0807.1304) published in PRB

The emission spectrum of individual high-quality ZnO nanowires consists of a series of Fabry-Pérot-like eigenmodes that extend far below the band gap of ZnO. Spatially resolved luminescence spectroscopy shows that light is emitted predominantly at both wire ends, with identical spectra reflecting standing wave polariton eigenmodes. The intensity of the modes increases supralinearly with the excitation intensity, indicating that the mode population is governed by scattering among polaritons. Due to strong light-matter interaction, light emission from a ZnO nanowire is not dictated by the electronic band diagram of ZnO but depends also on the wire geometry and the excitation intensity. Delocalized polaritons provide a natural explanation for the pronounced subwavelength guiding in ZnO wires that has been reported previously.

High-resolution zero kinetic energy (ZEKE) photoelectron spectrum of methyl bromide has been obtained using vacuum ultraviolet laser single photon excitations. The dominant feature of the spectrum is the origin band of the transition −X ~ 2 E 3/2 −X 1 A 1 −X~2E3/2−X1A1. The excitation of the totally symmetric vibrational mode, ν 2 (CH 3 ν2(CH3 symmetruc deformation), is observed. The 3 1 1 311 hot band is also present. All the bands obtained show similar rotational contours. Simulation of the rotational contour of the origin band yields the accurate first ionization potential of methyl bromide (85022.4±1.0cm −1 85022.4±1.0cm−1) and also the rotational constants of the X ~ 2 E 3/2 X~2E3/2 ground electronic state of the cation. The non-resonant two-photon ZEKE photoelectron spectrum of furan is also presented.

Double gratings form in anisotropic photorefractive crystals when two plane waves intersecting inside the crystal have both extraordinary and ordinary wave components. The effect can be observed by reading out the two gratings with extraordinary or ordinary light. Experiments confirm the theoretical predictions. The relevance of these results in using photorefractive crystals for holographic storage is discussed.

In an attempt to identify novel susceptibility genes predisposing to early-onset diabetes (EOD), we performed a genome-wide scan using 433 markers in 222 individuals (119 with diabetes) from 29 Scandinavian families with > or =2 members with onset of diabetes < or =45 years. The highest nonparametric linkage (NPL) score, 2.7 (P < 0.01), was observed on chromosome 1p (D1S473/D1S438). Six other regions on chromosomes 3p, 7q, 11q, 18q, 20q, and 21q showed a nominal P value

The role of water quality, particularly its impact on health, environment and wider well-being, are rarely acknowledged in the water–energy–food (WEF) nexus. Here we demonstrate the necessity to include water quality within the water dimension of the WEF nexus to address complex and multi-disciplinary challenges facing humanity. Firstly, we demonstrate the impact of water quality on the energy and food dimensions of the WEF nexus and vice versa at multiple scales, from households to cities, regions and transboundary basins. Secondly, we use examples to demonstrate how including water quality would have augmented and improved the WEF analysis and its application. Finally, we encourage hydrological scientists to promote relevant water quality research as addressing WEF nexus challenges. To make tangible progress, we propose that analysis of water quality interactions focuses initially on WEF nexus “hotspots,” such as cities, semi-arid areas, and areas dependent on groundwater or climate change-threatened meltwater.

The role of water quality, particularly its impact on health, environment and wider well-being, are rarely acknowledged in the water–energy–food (WEF) nexus. Here we demonstrate the necessity to include water quality within the water dimension of the WEF nexus to address complex and multi-disciplinary challenges facing humanity. Firstly, we demonstrate the impact of water quality on the energy and food dimensions of the WEF nexus and vice versa at multiple scales, from households to cities, regions and transboundary basins. Secondly, we use examples to demonstrate how including water quality would have augmented and improved the WEF analysis and its application. Finally, we encourage hydrological scientists to promote relevant water quality research as addressing WEF nexus challenges. To make tangible progress, we propose that analysis of water quality interactions focuses initially on WEF nexus “hotspots,” such as cities, semi-arid areas, and areas dependent on groundwater or climate change-threatened meltwater.

The role of water quality, particularly its impact on health, environment and wider well-being, are rarely acknowledged in the water–energy–food (WEF) nexus. Here we demonstrate the necessity to include water quality within the water dimension of the WEF nexus to address complex and multi-disciplinary challenges facing humanity. Firstly, we demonstrate the impact of water quality on the energy and food dimensions of the WEF nexus and vice versa at multiple scales, from households to cities, regions and transboundary basins. Secondly, we use examples to demonstrate how including water quality would have augmented and improved the WEF analysis and its application. Finally, we encourage hydrological scientists to promote relevant water quality research as addressing WEF nexus challenges. To make tangible progress, we propose that analysis of water quality interactions focuses initially on WEF nexus “hotspots,” such as cities, semi-arid areas, and areas dependent on groundwater or climate change-threatened meltwater.

We have recently described Pz-1, a benzimidazole-based type-2 RET and VEGFR2 inhibitor. Based on a kinome scan, here we show that Pz-1 is also a potent (IC50 50 ~ 1 nM), with a negligible effect against RET- and TRKA-negative cells. By testing mutations, known to mediate resistance to other compounds, RET G810R/S, but not L730I/V, E732K, V738A and Y806N, showed some degree of resistance to Pz-1. In the case of TRKA, G595R and F589L, but not G667C, showed some degree of resistance. In xenograft models, orally administered Pz-1 almost completely inhibited RET- and TRKA-mutant tumours at 1–3 mg/kg/day but showed a reduced effect on RET/TRKA-negative cancer models. The activity, albeit reduced, on RET/TRKA-negative tumours may be justified by VEGFR2 inhibition. Tumours induced by NIH3T3 cells transfected by RET G810R and TRKA G595R featured resistance to Pz-1, demonstrating that RET or TRKA inhibition is critical for its anti-tumourigenic effect. In conclusion, Pz-1 represents a new powerful kinase inhibitor with distinct activity towards cancers induced by oncogenic RET and TRKA variants, including some mutants displaying resistance to other drugs.

International audience; Tropomyosin receptor kinase (TRK) represents an attractive oncology target for cancer therapy related to its critical role in cancer formation and progression. NTRK fusions are found to occur in 3.3% of lung cancers, 2.2% of colorectal cancers, 16.7% of thyroid cancers, 2.5% of glioblastomas, and 7.1% of pediatric gliomas. In this paper, we described the discovery of the type-II pan-TRK inhibitor 4c through the structure-based drug design strategy from the original hits 1b and 2b. Compound 4c exhibited excellent in vitro TRKA, TRKB, and TRKC kinase inhibitory activity and anti-proliferative activity against human colorectal carcinoma derived cell line KM12. In the NCI-60 human cancer cell lines screen, compound 4g demonstrated nearly 80% of growth inhibition for KM12, while only minimal inhibitory activity was observed for the remaining 59 cancer cell lines. Western blot analysis demonstrated that 4c and its urea cousin 4k suppressed the TPM3-TRKA autophosphorylation at the concentrations of 100 nM and 10 nM, respectively. The work presented that 2-(4-(thieno[3,2-d]pyrimidin-4-ylamino)phenyl)acetamides could serve as a novel scaffold for the discovery and development of type-II pan-TRK inhibitors for the treatment of TRK driven cancers.

Neural stem cells (NSC) can be isolated from a variety of adult tissues and become a valuable cell source for the repair of peripheral and central nervous diseases. However, their origin and identity remain controversial because of possible de-differentiation/transdifferentiation or contaminations by hematopoietic stem cells (HSCs) or mesenchymal stem cells (MSCs). We hypothesize that the commonly used NSC culture medium can induce committed cartilage chondrocytes to de-differentiate and/or trans-differentiate into neural cell lineages. Using a biological isolation and purification method with explants culture, we here show that adult rat clavicle cartilage chondrocytes migrate out from tissue blocks, form sphere-like structures, possess the capability of self-renewal, express nestin and p75NTR, markers for neural crest progenitors, and differentiate into neurons, glia, and smooth muscle cells. Comparing with adult cartilage, the spherical-forming neural crest cell-like cells downregulate the chondrocytic marker genes, including collagen II, collagen X, and sox9, as well as neural-lineage repressors/silencers REST and coREST, but upregulate a set of well-defined genes related to neural crest cells and pro-neural potential. Nerve growth factor (NGF) and glial growth factor (GGF) increase glial and neuronal differentiation, respectively. These results suggest that chondrocytes derived from adult clavicle cartilage can become neural crest stem-like cells and acquire neuronal phenotypes in vitro. The possible de-differentiation/trans-differentiation mechanisms underlying the conversion were discussed Refereed/Peer-reviewed