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The fractional arboricity of a digraph D $D$, denoted by γ(D) $\gamma (D)$, is defined as γ(D)=maxH⊆D,|V(H)|>1|A(H)||V(H)|−1 $\gamma (D)=\mathop{\max }\limits_{H\subseteq D,|V(H)|\gt 1}\frac{|A(H)|}{|V(H)|-1}$. Frank proved that a digraph D $D$ decomposes into k $k$ branchings, if and only if Δ−(D)≤k ${{\rm{\Delta }}}^{-}(D)\le k$ and γ(D)≤k $\gamma (D)\le k$. In this paper, we study digraph analogues for the Nine Dragon Tree Conjecture. We conjecture that, for positive integers k $k$ and d $d$, if D $D$ is a digraph with γ(D)≤k+d−kd+1 $\gamma (D)\le k+\frac{d-k}{d+1}$ and Δ−(D)≤k+1 ${{\rm{\Delta }}}^{-}(D)\le k+1$, then D $D$ decomposes into k+1 $k+1$ branchings B1,...,Bk,Bk+1 ${B}_{1},\ldots ,{B}_{k},{B}_{k+1}$ with Δ+(Bk+1)≤d ${{\rm{\Delta }}}^{+}({B}_{k+1})\le d$. This conjecture, if true, is a refinement of Frank's characterization. A series of acyclic bipartite digraphs is also presented to show the bound of γ(D) $\gamma (D)$ given in the conjecture is best possible. We prove our conjecture for the cases d≤k $d\le k$. As more evidence to support our conjecture, we prove that if D $D$ is a digraph with the maximum average degree mad(D)≤2k+2(d−k)d+1 $\,\text{mad}\,(D)\le 2k+\frac{2(d-k)}{d+1}$ and Δ−(D)≤k+1 ${{\rm{\Delta }}}^{-}(D)\le k+1$, then D $D$ decomposes into k+1 $k+1$ pseudo‐branchings C1,...,Ck,Ck+1 ${C}_{1},\ldots ,{C}_{k},{C}_{k+1}$ with Δ+(Ck+1)≤d ${{\rm{\Delta }}}^{+}({C}_{k+1})\le d$. [ABSTRACT FROM AUTHOR]

Two lead borate-nitrates Pb6O4(BO3)(NO3) and Pb6O2(BO3)2(NO3)F were obtained by the high-temperature flux method. Interestingly, their crystal structure consists of anion-centered [OPb4] tetrahedra and π-conjugated BO3 and NO3 units. The first principles calculations indicate that both compounds show large birefringence. [ABSTRACT FROM AUTHOR]

• Ln3+ complexes with organic ligands have unique optical features. • Incorporating of Ln3+ complexes into polymers matrices can improve their stability. • Synthesis methods of Ln3+ complex-containing polymers are summarized in this review. • The critical strategies to prepare self-healing polymers will be discussed in detail. • Various emerging applications of luminescent polymers are summarized in this review. Lanthanide (Ln3+) complexes with organic ligands have recently gained extensive attention due to their unique optical features such as high color purity, narrow and intense emission bands and long excited state lifetimes, showing diverse applications in tunable lasers, optical amplifiers, biomedical diagnosis, high density information storage and so on. However, some inherent shortcomings, such as poor stability (photo-, thermal- and mechanical), low processability and the tendency to aggregate significantly, limit their full exploitation in practical applications. Incorporating of Ln3+ complexes into polymers matrices are effective means to improve their properties and broaden their applications. In recent decades, significant progress has been made in Ln3+ complexes-containing polymers, varying from structural evolution of ligand molecules and polymers to application expansion of luminescent functional polymers. This review will systematically summarize the key points in the synthesis methods (including both physical doping and chemical cross-linking) of Ln3+ complexes-containing polymers. The critical strategies to prepare self-healing luminescent polymers will be discussed in detail. We then review the emerging applications of Ln3+ complexes-containing polymers ranging from light-conversion films, organic light-emitting diodes, bio-imaging to temperature sensing applications. At the end of this review, we will provide an outlook on the opportunities and challenges of Ln3+ complexes-containing polymers. [ABSTRACT FROM AUTHOR]

In this paper, we characterize a mixed graph F which contains k edge and arc‐disjoint spanning mixed arborescences F1,...,Fk, such that for each v∈V(F), the cardinality of {i∈[k]:vis the root ofFi} lies in some prescribed interval. This generalizes both Nash‐Williams and Tutte's theorem on spanning tree packing for undirected graphs and the previous characterization on digraphs which was given by Cai and Frank. [ABSTRACT FROM AUTHOR]

This paper studies the following packing problem: Given a mixed graph F with vertex set V , a matroid M on a set S = { s 1 , ... , s k } along with a map π : S → V , find k mutually edge and arc-disjoint mixed arborescences T 1 , ... , T k in F with roots π (s 1) , ... , π (s k) , such that, for any v ∈ V , the set { s i : v ∈ V (T i) } is independent and its rank reaches the theoretical maximum. This problem was mentioned by Fortier, Király, Léonard, Szigeti and Talon in [Old and new results on packing arborescences in directed hypergraphs, Discrete Appl. Math. 242 (2018), 26-33]; Matsuoka and Tanigawa gave a solution to this in [On reachability mixed arborescence packing, Discrete Optimization 32 (2019) 1-10]. In this paper, we give a new characterization for above packing problem. This new characterization is simplified to the form of finding a supermodular function that should be covered by an orientation of each strong component of a matroid-based rooted mixed graph. Our proofs come along with a polynomial-time algorithm. The technique of using components opens some new ways to explore arborescence packings. [ABSTRACT FROM AUTHOR]

The spectral mismatch between the distribution of sunlight (AM1.5G) and crystalline silicon (c-Si) solar cells is one of the most important limiting factors of the conversion efficiency of photovoltaic (PV) devices. As an effective solution, the use of the luminescence down-shifting (LDS) technique is an important way to improve the short-wavelength response of a solar cell by shifting high-energy photons to the visible range. Herein, a large-area (17 × 17 cm2) luminescent thin film consisting of a ternary europium (Eu3+) complex and polyvinyl alcohol (PVA) was successfully constructed through a solution casting method and further developed as an effective LDS layer to improve the photoelectric conversion efficiency of c-Si solar cells with a large active area (235 cm2). The self-standing LDS layer is flexible, transparent and easily attachable to the surface of the solar cell module. Compared with the uncoated c-Si solar cell, the one coated with the LDS layer displayed an enhancement of ∼15% in external quantum efficiency (EQE) due to the high luminescence quantum yield of the Eu3+ complex doped inside the layer. These results demonstrate that use of a large area luminescent film embedding an Eu3+ complex is a versatile and effective strategy to improve the conversion efficiency of large size PV devices, giving rise to its great potential application as an LDS material. [ABSTRACT FROM AUTHOR]

Lanthanide complex-based luminescent organic-inorganic hybrid materials are highly interesting for a broad range of application fields. The combination of lanthanide complexes with the synthetic clay, Laponite, is now attracting the interest of scientists due to the unique features of the synthetic clay. However, most of the reported literature are involved with the adsorption of lanthanide complexes on the clay particles. Taking the covalent incorporation of lanthanide complex into clay and satisfying the further coordinate with central lanthanide ion into account, herein, we reported a facile strategy of covalent grafting lanthanide complexes to the clay via the reaction of the terminal triethoxy groups of triethoxysilylated ligand (phenSi) and the surface OH groups of the clay. The successful grafting of the complexes was confirmed by the FT-IR spectra, 29Si solid-state NMR spectra and the luminescent data. And the nitrogen atoms of Phen moieties which are covalently grafted to the clay provide the chance to prepare luminescent hybrid materials with larger coordination number. [ABSTRACT FROM AUTHOR]

Prior to the beginning of the World Meteorological Organization's (WMO) Solid Precipitation Inter-Comparison Experiment (SPICE, 2013–2015), two precipitation measurement intercomparison sites were established in Saskatchewan to help assess the systematic bias in the automated gauge measurement of solid precipitation and the impact of wind on the undercatch of snow. Caribou Creek, located in the southern boreal forest, and Bratt's Lake, located in the southern plains, are a contribution to the international SPICE project but also to examine national and regional issues in measuring solid precipitation, including regional assessment of wind bias in precipitation gauges and windshield configurations commonly used in Canadian monitoring networks. Overlapping with WMO-SPICE, the Changing Cold Regions Network (CCRN) Special Observation and Analysis Period (SOAP) occurred from 2014 to 2015, involving other enhanced observations and cold regions research projects in the same geographical domain as the Saskatchewan SPICE sites. Following SPICE, the two Saskatchewan sites continued to collect core meteorological data (temperature, humidity, wind speed, etc.) as well as precipitation observations via several automated gauge configurations, including the WMO automated reference and the Meteorological Service of Canada's (MSC) network gauges. In addition, manual snow surveys to collect snow cover depth, density, and water equivalent were completed over the duration of the winter periods at the northern Caribou Creek site. Starting in the fall of 2013, the core intercomparison precipitation and ancillary data continued to be collected through the winter of 2017. Automated observations were obtained at a temporal resolution of 1 min, subjected to a rigorous quality control process, and aggregated to a resolution of 30 min. The manual snow surveys at Caribou Creek were typically performed every second week during the SPICE field program with monthly surveys following the end of the SPICE intercomparison period. The Saskatchewan SPICE data are available at 10.18164/63773b5b-5529-4b1e-9150-10acb84d59f0 (Smith and Yang, 2018). The data collected at the Saskatchewan SPICE sites will continue to be useful for transfer function testing, numerical weather prediction and hydrological forecasting verification, ground truth for remote-sensing applications, as well as providing reference precipitation measurements for other concurrent research applications in the cold regions. [ABSTRACT FROM AUTHOR]

MicroRNA-3666 (miR-3666) acts as a tumor suppressor in cervical cancer, non-small cell lung cancer and thyroid carcinoma; however, the function of miR-3666 in colorectal cancer (CRC) remains largely unknown. In the present study, was demonstrated that miR-3666 was significantly downregulated in CRC tissues compared with in adjacent normal tissues by reverse transcription-quantitative polymerase chain reaction. Additionally, miR-3666 may serve as a prognostic biomarker for patients with CRC. Via functional experiments, the present study reported that miR-3666 overexpression significantly inhibited the proliferation, migration and invasion of CRC cells as determined by Cell Counting Kit-8 and Transwell assays, and vice versa. In addition, miR-3666 was reported to directly target special AT-rich sequence binding protein 2 (SATB2) in CRC cells; overexpression of miR-3666 significantly suppressed the expression of SATB2 in CRC cells as determined by western blotting. Furthermore, an inverse correlation was observed between the expression levels of miR-3666 and SATB2 in CRC tissues. Restoration of SATB1 expression significantly reversed the effects of miR-3666 mimic on CRC cells. In summary, the results of the present study indicated that miR-3666 may serve as a tumor suppressor in CRC by targeting SATB2. [ABSTRACT FROM AUTHOR]

We succeed in developing hydrogels that gain both mechanical strength and luminescent emission under repetitive mechanical loading through integrating of mechanical stimuli and substance supplying of monomers and lanthanide emitting center. [Display omitted] • For typical synthetic polymeric materials, continue mechanical loading usually leads to damage and even failure. • Simultaneous self-strengthen in both mechanical performance and luminescence intensity are realized through bond rupture-initiated mechanoradical polymerization. • This strategy proves the feasibility of imparting desired functions to the double-network hydrogel by mechanical stamping. For typical synthetic materials, continue mechanical loading usually cause damage and even failure, because they are closed systems, without substance exchange with surroundings and structural reconstruction after damage. Double-network (DN) hydrogels have recently been demonstrated to generate radicals under mechanical loading. In this work, DN hydrogel provided with sustained monomer and lanthanide complex supply undergo self-growth, and thus simultaneous self-strengthen in both mechanical performance and luminescence intensity are realized through bond rupture-initiated mechanoradical polymerization. This strategy proves the feasibility of imparting desired functions to the DN hydrogel by mechanical stamping, and provides a new strategy for the design of luminescent soft materials with high fatigue resistance. [ABSTRACT FROM AUTHOR]

The fractional arboricity of a graph G , denoted by γ f ( G ) , is defined as γ f ( G ) = max H ⊆ G , v ( H ) > 1 ⁡ e ( H ) v ( H ) − 1 . The famous Nash-Williams' Theorem states that a graph G can be partitioned into at most k forests if and only if γ f ( G ) ≤ k . A graph is d -bounded if it has maximum degree at most d . The Nine Dragon Tree (NDT) Conjecture [posed by Montassier, Ossona de Mendez, Raspaud, and Zhu, at [11] ] asserts that if γ f ( G ) ≤ k + d k + d + 1 , then G decomposes into k + 1 forests with one being d -bounded. In this paper, it is proven that the Nine Dragon Tree Conjecture is true for all the cases in which d = 1 . [ABSTRACT FROM AUTHOR]

Herein, a flexible and transparent film consisting Eu 3+ /Tb 3+ lanthanide complexes and poly(methylmethacrylate) was constructed via solution casting method, and further developed as a ratiometric luminescent thermometer with an excellent linear response to temperature variation from 77 to 297 K. The thermometer displays higher photo- and thermostability than corresponding pure complexs. Based on that the emission intensity ratio of 5 D 4  →  7 F 5 transition (Tb 3+ ) to 5 D 0  →  7 F 2 transition (Eu 3+ ) can be linearly related to the temperature, the resulting thermometer is not only more reliable than single Eu 3+ (or Tb 3+ ) material based on one emission, and but also has higher sensitivity than other types of luminescent thermometers. This work highlights the practical applications of luminescent films in temperature-sensing fields. [ABSTRACT FROM AUTHOR]

A coloring of the edges of a graph G is strong if each color class is an induced matching of G. The strong chromatic index of G, denoted by [ABSTRACT FROM AUTHOR]

Lanthanide-based organic-inorganic hybrid materials have shown important potential as luminescent detectors for various applications. We developed a nanohybrid luminescence sensor composed of Eu 3+ -β-diketonate complexes. The new composite shows remarkable luminescence enhancement in presence of cationic surfactants. We tested it successfully for facile detection of cationic surfactants in aqueous solution. The result is that it is useful as luminescence sensor to distinguish cationic from other type of surfactants. It allows highly reliable, simple, fast, and sensitive detection of cationic surfactants. [ABSTRACT FROM AUTHOR]

A stable europium (III) ternary complex denoted as Eu(TTA) 3 -tpyIL was obtained by the coordination of Eu(TTA) 3 ·2H 2 O to a terpyridine-functionalized ionic liquid. The luminescent properties were investigated at room temperature. From the studies of thermo-and photo-stability, compared with the Eu(TTA) 3 ·2H 2 O, both emission intensity and luminescence decay based on the complex was almost no significant decrease after enduring high temperature and long-term UV irradiation. Then red-light-emitting diodes (LEDs) were fabricated by coating complexes onto 370 nm-emitting InGaN chips. The light emission from the InGaN chips could be completely absorbed in the spectra of LED. The chromaticity coordinates of them were calculated from emission spectra and show in CIE color diagram. All these results indicate that the Eu(III) complex is promising as phosphor for fabrication of WLEDs. [ABSTRACT FROM AUTHOR]

Ethylenediamine, as important chemical raw materials and fine chemical intermediates, has been widely applied in various industries. Detection of Ethylenediamine is highly desirable for a number of chemical industries due to its potential threat to human health. Chemical sensing bears an advantage over the traditional analysis method (liquid chromatography) owing to its sensing ability of visual inspection (such as the change in color, luminescence etc). Herein we report a new and solid luminescent material by encapsulating of terbium-acetylacetonate complexes within the cavities of Y type zeolite displaying obvious changes in luminescence colors triggered by solvent vapors, with excellent selectivity for En vapor. [ABSTRACT FROM AUTHOR]

Abstract. This study, based on the analyses of long-term discharge and Normalized Difference Vegetation Index (NDVI) data, revealed a strong seasonal consistency between NDVI and discharge over the Mackenzie River Basin in Canada. The flow–NDVI association is particularly strong in the early growing season (May to the 1st half of June). During this period, discharge rapidly rises and reaches the peak, whereas NDVI increases around the 1st half of May and reaches the maximum at the 2nd half of July. In the mid- and late summer, both discharge and NDVI decline gradually. Correlation analyses identify 2 sensitive periods, i.e., May to June and the 2nd half of July to the 1st half of September, when NDVI significantly responds to discharge variations. In the first period, the half-month NDVI highly correlates to the 1st half of May discharge, indicating that spring flow has a strong influence on vegetation growth in the early growing season. Spatially, almost all of the basin shows a high correlation, except Mackenzie and the Rocky Mountains and the region near the eastern edge of the basin. For the 2nd period, from the 2nd half of July to the 1st half of September, the NDVI relates closely to discharge with lags of 0–5 half-months. Trends analyses suggest river discharge increased during 1982 to 2006 in most seasons except summer. The NDVI trends during the growing season (May to September) clearly correspond to discharge changes. Examination of extreme flow years and corresponding NDVI conditions over the basin also reveal that a lower runoff was associated with a lower basin NDVI with an earlier maximum, whereas the higher flow was linked with a higher NDVI and a longer growing season. [ABSTRACT FROM PUBLISHER]

This study systematically analyzes long-term (1973–2011) daily flow data collected near the Mackenzie basin outlet. It clearly defines the variability, extreme events, and changes in daily flow records over the past 4 decades. The results of this study accurately determine the seasonal cycle of river discharge, including the range of highest and lowest daily flows. The interannual variation of daily flow is generally small in the cold season, highest in the spring melt period, and large over the summer months mainly due to rainfall storm activities and associated floods. This study also shows that Mackenzie River flow regime has changed over the past 4 decades due to climate variation, with the advance of snowmelt peak timing by several days, decrease in maximum spring flows by about 3000 m 3 /s, and weak rise of cold season base flows. These results are the consequence of hydrological response to regional climate warming, and they provide new knowledge to improve our understanding of large-scale environmental changes over the broader northern regions. [ABSTRACT FROM AUTHOR]

Herein we report the red-emitting nanocomposites via the adsorption of 2-thenoyltrifluoroacetone on the Eu 3+ -containing Laponite that was obtained by substituting the positive Na + ions with Eu 3+ via an ion exchange procedure. The in-situ formation of luminescent Eu 3+ complexes is confirmed by Fourier Transform Infrared spectra and luminescent data. X-ray diffraction patterns suggest that at least partial complexes are intercalated within the interlayers of the Laponite. Furthermore, we observed that the solvent used in the ion exchange step shows pronounced influence on the luminescent behaviour of the final nanocomposites. In addition, the luminescent nanocomposite displays high photo- and thermo-stability. [ABSTRACT FROM AUTHOR]

This paper examines the key modern infrastructure of telecommunications in early Republican China, through the eyes of a Japanese, Nakayama Ryûji, who served as a telecommunications adviser to the Chinese government from 1913 to 1928. Nakayama's numerous reports and recommendations to his Chinese employer and frequent confidential dispatches to the Japanese government, when read together, constitute a fascinating prism. They not only reveal problems as well as the potential in China's telecommunications sector, they also highlight Japan's efforts to compete with other foreign actors in China through the provision of Japanese equipment, expertise, and loans. While Nakayama strove to shape China's telecommunications development in ways that would, in his view, benefit both China and Japan, his efforts were often undercut by the aggressive actions of the Japanese government in China, such as the infamous Twenty-One Demands. Though promising at first, Japan's influence on China's modernization in the early Republican era came to be more limited, especially when compared with the final decade of the Qing Dynasty. Ultimately, what can be seen through this Japanese prism confirms that the development of an information infrastructure in modern China, as elsewhere, was as much shaped by technological and economic forces as it was influenced by political and diplomatic factors. [ABSTRACT FROM PUBLISHER]

Highlights: [•] Bush Gauge measures 20–50% more snowfall than DFIR for wind speeds of 6–7m/s. [•] DFIR measurements need corrections for wind-induced undercatch of snowfall. [•] Past WMO study underestimated DFIR catch, impacting national gauge assessment. [Copyright &y& Elsevier]

Abstract: The game coloring number of the square of a graph , denoted by , was first studied by Esperet and Zhu. The -game coloring number, denoted by -, is defined like the game coloring number, except that on each turn Alice makes moves and Bob makes moves. For a graph , the maximum average degree of is defined as is a subgraph of . Let be an integer. In this paper, by introducing a new parameter , which is defined through orientations and orderings of the vertices of , we show that if , then -. This implies that if is a partial -tree and , then -; if is planar, then there exists a constant such that . These improve previous corresponding known results. For and , we prove that -. [Copyright &y& Elsevier]

Abstract: Let be a directed graph. A transitive fraternal augmentation of is a directed graph with the same vertex set, including all the arcs of and such that for any vertices , [1.] if and then or (fraternity); [2.] if and then (transitivity). In this paper, we explore some generalization of the transitive fraternal augmentations for directed graphs and its applications. In particular, we show that the 2-coloring number , where () denotes the greatest reduced average density with depth of a graph ; we give a constructive proof that bounds the distance -coloring number with a function . On the other hand, . We also show that an inductive generalization of transitive fraternal augmentations can be used to study nonrepetitive colorings of graphs. [Copyright &y& Elsevier]

Abstract: This paper investigates a competitive version of the coloring game on a finite graph . An asymmetric variant of the -relaxed coloring game is called the -relaxed -coloring game. In this game, two players, Alice and Bob, take turns coloring the vertices of a graph , using colors from a set , with . On each turn Alice colors vertices and Bob colors vertices. A color is legal for an uncolored vertex if by coloring with color , the subgraph induced by all the vertices colored with has maximum degree at most . Each player is required to color an uncolored vertex legally on each move. The game ends when there are no remaining uncolored vertices. Alice wins the game if all vertices of the graph are legally colored, Bob wins if at a certain stage there exists an uncolored vertex without a legal color. The -relaxed -game chromatic number of , denoted -, is the least for which Alice has a winning strategy in the -relaxed -coloring game. This paper extends the well-studied activation strategy of coloring games to relaxed asymmetric coloring games. The extended strategy is then applied to the -relaxed -coloring games on planar graphs, partial -trees and -pseudo-partial -trees. This paper shows that for planar graphs , if , then - for all . If is a partial -tree, , then - for all . If is an -pseudo-partial -tree, , let , then - for all . For planar graphs and , - for all . These results extend the corresponding -relaxed -coloring game results to more generalized asymmetric cases. [Copyright &y& Elsevier]

Abstract: This paper investigates a competitive version of the coloring game on a finite graph . An asymmetric variant of the -relaxed coloring game is called the -relaxed -coloring game. In this game, two players, Alice and Bob, take turns coloring the vertices of a graph , using colors from a set , with . On each turn Alice colors vertices and Bob colors vertices. A color is legal for an uncolored vertex if by coloring with color , the subgraph induced by all the vertices colored with has maximum degree at most . Each player is required to color an uncolored vertex legally on each move. The game ends when there are no remaining uncolored vertices. Alice wins the game if all vertices of the graph are legally colored, Bob wins if at a certain stage there exists an uncolored vertex without a legal color. The -relaxed -game chromatic number, denoted by , of is the least for which Alice has a winning strategy in the -relaxed -coloring game. The -relaxed -coloring game has been well studied and there are many interesting results. For the -relaxed -coloring game, this paper proves that if a graph has an orientation with maximum outdegree and , then for all ; If , then - for all . [Copyright &y& Elsevier]

This study examined heat flux from 15 Canadian northern rivers that drain to the Arctic Ocean and the Hudson/James Bay. Based on statistical analysis of available water temperature and discharge data, we determined patterns and characteristics of discharge, water temperature, and heat flux in relation to seasonal air temperature and precipitation. We found similar seasonal cycles of discharge and water temperature across the study region, i.e. most rivers experiencing maximum discharge in June/July and highest water temperatures in July/August. The mean flows during the open water season (May to Oct.) vary from west to east along the Arctic Coast (with higher yield from the Mackenzie and Peel rivers), while river flows are higher with warmer water temperatures in western and southern Hudson Bay. The summed heat flux for the studied rivers was about 10.0 × 1012 MJ along the Arctic Coast and 2.0x1012MJ around the Hudson Bay. Among the 9 rivers flowing directly into the Arctic Ocean, the Mackenzie River with the highest flow and warmest water temperature delivered the highest heat flux, i.e. average 9.5 × 1012 MJ over the open water season during 1960–2015. These observed patterns in discharge, water temperature and heat flux were generally consistent with CHANGE model simulations for most rivers in northern Canada. The outcomes of our study provide critical knowledge of river thermal condition and heat transport to the northern seas, which will be useful for large-scale climate and ocean model development and validation, and climate/hydrology change investigations in the broader northern regions. • Determined patterns of discharge (Q), water temperature (WT), and heat flux (HF) for 15 northern rivers in Canada. • Similar seasonal cycles of Q, WT and HF for the rivers, most rivers with max Q in June/July and highest WT in July/August. • Total warm season HF of 10.0x1012 MJ from the 9 rivers along Arctic Coast and 2.0x1012MJ for the 6 rivers into Hudson Bay. • Mackenzie River with highest Q and warmest WT delivered highest HF, 9.5x1012 MJ in open water season during 1960-2015. • Observations and CHANGE model HF simulations were generally consistent for most rivers in northern Canada. [ABSTRACT FROM AUTHOR]

Abstract: This paper extends the widely used activation strategy of the marking game on graphs to asymmetric marking games. The extended activation strategy is then applied to asymmetric marking games on chordal graphs, -pseudo partial -trees and interval graphs. Our results improve earlier upper bounds on and , where and denote the classes of interval and chordal graphs with maximum clique size respectively. Moreover, the upper bound of is tight when is a multiple of . [Copyright &y& Elsevier]

Abstract: This paper investigates the asymmetric marking games on line graphs. Suppose G is a graph with maximum degree and G has an orientation with maximum outdegree k, we show that the -game coloring number of the line graph of G is at most . When , this improves some known results of the game coloring number of the line graphs. [Copyright &y& Elsevier]

Abstract: This study systematically analyzes long-term (1950–1992) stream temperature records for the major sub-basins within the Lena River watershed in order to describe water temperature regimes over the various parts of the Lena watershed and document significant stream temperature changes induced by reservoir regulation, and by natural variations/changes. The results show that the open water season can be divided into three consecutive stages—“increasing temperature stage” in the early open water season, “stable temperature stage” in the mid-warm season, and “decreasing temperature stage” in the late open water season. Temperature conditions are similar over the Aldan and Upper Lena regions. However, stream temperatures at the Lena basin outlet are up to 8 °C lower than those over the southern sub-basins. This suggests that the latitudinal difference in climatic variables, such as air temperature, might be the major control on stream temperature regime. Results also demonstrate that the reservoir regulation has a strong influence on the regional water temperature regime and change in the regulated sub-basin. Reservoir regulation has increased (decreased) the downstream water temperatures in the Vilui valley during the early (mid) open water season. Trend analyses show consistent warming trends across the entire Lena River basin in the early open water season. This may indicate a response to earlier snowmelt over the Lena River watershed. Trend results also demonstrate that the Aldan tributary, without much human impact, experiences warming (cooling) trends in the first (second) half of the open water season, leading to a stream temperature regime shift toward early open water season. The upper Lena River has warming (cooling) trends in the early (mid-late) open water season. Over the regulated Vilui tributary, however, stream temperatures have significantly increased in the early and late parts of the warm season due to combined effects of natural changes and reservoir regulation. Over the Lena basin as a whole, strong positive correlations have been found between the basin mean monthly air and water temperatures during the warm season. Increasing water temperatures were observed during the early and mid-June. Because of stream temperature increase in this peak flow period, the Lena River heat flux has gone up by 23% in June. This may have considerable impact on the thermal conditions of the Laptev Sea in the early summer season. [Copyright &y& Elsevier]

Abstract: Historical data analyses show that the Lena River and its major tributaries experienced an extended low water period over 1936–1957 and high water periods over 1974–1983 and 1988–2001. Higher than normal river discharge and annual precipitation is particularly pronounced since the late 1960s due to large-scale changes in atmospheric circulation patterns. The trend in runoff observed in the Lena River basin increased by 10% from 1936 to 2001 due to extended wet periods during the second part of last century. The trend is weakened for the Vilui River basin since it experiences reservoir regulation, which causes additional water losses through reservoir filling and increased evaporation. Runoff regulation strongly affects the winter runoff regime of both the Vilui River and the lower reaches of the Lena River causing an increased winter discharge at the Lena river outlet station of approximately 33%. [Copyright &y& Elsevier]

This paper presents the results of bias corrections of Chinese standard precipitation gauge (CSPG) measurements for wind-induced undercatch, a trace amount of precipitation, and wetting loss. Long-term daily data of precipitation, temperature, and wind speed during 1951–98 at 710 meteorological stations in China were used for this analysis. It is found that wind-induced gauge undercatch is the greatest error in most regions, and wetting loss and a trace amount of precipitation are important in the low-precipitation regions in northwest China. Monthly correction factors ratio of corrected amount to measured amount of precipitation differ by location and by type of precipitation. Considerable interannual variation of the corrections exists in China due to the fluctuations of wind speed and frequency of precipitation. More importantly, annual precipitation has been increased by 8 to 740 mm with an overall mean of 130 mm at the 710 stations over China because of the bias corrections for the study period. This corresponds to 6%–62% increases (overall mean of 19% at the 710 stations over China) in gauge-measured yearly total precipitation over China. This important finding clearly suggests that annual precipitation in China is much higher than previously reported. The results of this study will be useful to hydrological and climatic studies in China. [ABSTRACT FROM AUTHOR]

This study analyzes long-term (1935–99) monthly discharge data for the major sub-basins within the Yenisei River watershed in order to document significant streamflow changes induced by reservoir regulations and by natural variations/changes. The results show that both the unregulated upper basin and major lower streams of the watershed experienced streamflow decreases in the early melt period and discharge increases in the late melt season. These changes in snowmelt runoff pattern suggest a delay in snowcover melt in the Yenisei basin perhaps associated with cooling trends during the snowmelt months over central Siberia. This study also demonstrates that the reservoir regulation has significantly altered the monthly discharge regimes in northeast and the upper portions of the Yenisei basin. Constructions of four large dams in the northeast Yensiei regions reduced the summer peak flows in the Angara valley by 15–30% and increased the winter low flows by 5–30%. Operations of two large reservoirs in the upper Yenisei regions enhanced the winter flows by 45–85% and reduced the summer flows by 10–50%. These alterations lead to a streamflow regime change toward less seasonal variation over the eastern and lower Yenisei basin. Because of reservoir regulations, discharge records collected at the Yenisei basin outlet do not always represent natural changes and variations, they tend to underestimate the natural streamflow trends in summer and overestimate the trends in winter and fall seasons. Cold season discharge increase over the Yenisei river is not natural-caused, but mainly the effect of reservoir regulations in the Yenisei basin. [Copyright &y& Elsevier]

The influences of surface climate conditions and atmospheric circulation on seasonal river discharges of the Ob, Yenisei, and Lena River basins during 1936–95 have been examined and quantified. Climatic variables include seasonal basin-averaged surface air temperatures, precipitation, maximum snow accumulation depth, and starting and ending dates of the basins' continuous snow cover. Atmospheric circulation is represented by the Northern Hemisphere annular mode (NAM) index. The combinations of these climatic and atmospheric variables explain about 31% to 55% of the variance of the annual total discharges of these rivers. On average, climatic and atmospheric variables explain 35% to 69% variance of spring discharges, 34% to 47% variance of summer discharges, 21% to 50% variance of fall discharges, and 18% to 36% variance of winter discharges. This study reveals that the spring thermal condition is most significant for spring discharge and negatively affects summer discharge. Climatic conditions during the previous winter through fall influence fall discharges, while the atmospheric conditions of the previous summer and fall affect winter discharges. Also, winter snow accumulation influences summer and fall discharges of the Ob and Yenisei Rivers but affects winter and spring discharges of the Lena River, suggesting the importance of topography and permafrost conditions to river discharges over high-latitude regions. [ABSTRACT FROM AUTHOR]

A new cesium hydroxyborate CsB3O4(OH)2, was designed and synthesized by a hydrothermal method. Remarkably, CsB3O4(OH)2 presents novel [B3O4(OH)2]∞ chains formed by [B3O4(OH)2] fundamental building blocks (FBBs). The report of less common [B3O4(OH)2] FBBs and [B3O4(OH)2]∞ chains in CsB3O4(OH)2 enriches the structural diversity of hydroxyborates. In addition, CsB3O4(OH)2 has a wide transparent window in the DUV spectral range and a large birefringence. [ABSTRACT FROM AUTHOR]

Combining π‐conjugated and non‐π‐conjugated groups is an important strategy for synthesizing new nonlinear optical (NLO) crystals. However, the second harmonic generation (SHG) response and optical anisotropy can be limited by improper spatial alignment of these functional groups in the crystal structure. In this work, it is revealed that non‐π‐conjugated [NH2SO3] group acts as both hydrogen bond donor and acceptor, effectively regulating the 2D planar structure formed by π‐conjugated [C4N3H6] groups. The resulting organic–inorganic hybrid crystal C4N3H6SO3NH2 exhibits a strong SHG response (2.5 × KDP), large optical anisotropy (0.233@546 nm), and blue‐violet and green fluorescence near 360 and 520 nm, respectively. This work expands the methodology for creating new NLO crystals through organic–inorganic hybridization, while also showcasing the potential of C4N3H6SO3NH2 as a multifunctional optical material. [ABSTRACT FROM AUTHOR]

Presents an essay focusing on the historical writings on the massacre in Nanjing, China.

The standard 8'' nonrecording precipitation gauge has been used historically by the National Weather Service (NWS) as the official precipitation measurement instrument of the U.S. climate station network. From 1986 to 1992, the accuracy and performance of this gauge (unshielded or with an Alter shield) were evaluated during the WMO Solid Precipitation Measurement Intercomparison at three stations in the United States and Russia, representing a variety of climate, terrain, and exposure. The double-fence intercomparison reference (DFIR) was the reference standard used at all the intercomparison stations in the Intercomparison project. The Intercomparison data collected at different sites are compatible with respect to the catch ratio (gauge measured/DFIR) for the same gauges, when compared using wind speed at the height of gauge orifice during the observation period. The effects of environmental factors, such as wind speed and temperature, on the gauge catch were investigated. Wind speed was found to be the most important factor determining gauge catch when precipitation was classified into snow, mixed, and rain. The regression functions of the catch ratio versus wind speed at the gauge height on a daily time step were derived for various types of precipitation. Independent checks of the equations have been conducted at these intercomparison stations and good agreement was obtained. Application of the correction procedures for wind, wetting loss, and trace amounts was made on a daily basis at Barrow, Alaska, for 1982 and 1983, and, on average, the gauge-measured precipitation was increased by 20% for rain and 90% for snow. [ABSTRACT FROM AUTHOR]

Edmonds' fundamental theorem on arborescences characterizes the existence of k pairwise arc-disjoint spanning arborescences with prescribed root sets in a digraph. In this paper, we study the problem of packing branchings in digraphs under cardinality constraints on their root sets by arborescence augmentation. Let D = (V + x , A) be a digraph, P = { I 1 , ... , I l } be a partition of [ k ] , c 1 , ... , c l , c 1 ′ , ... , c l ′ be nonnegative integers such that c α ≤ c α ′ for α ∈ [ l ] , F 1 , ... , F k be k arc-disjoint x -arborescences in D such that ∑ i ∈ I α d F i + (x) ≤ c α ′ for α ∈ [ l ]. We give a characterization on when F 1 , ... , F k can be completed to arc-disjoint spanning x -arborescences F 1 ∗ , ... , F k ∗ such that for any α ∈ [ l ] , c α ≤ ∑ i ∈ I α d F i ∗ + (x) ≤ c α ′ . [ABSTRACT FROM AUTHOR]

[Display omitted] • Eu(DBM) 3 DETA is a newly synthesized, unreported lanthanide crystal complex. • Eu(DBM) 3 DETA has both excellent photoluminescence and triboluminescence properties. • Eu(DBM) 3 DETA can recover to its original PL and TL properties after recrystallization. • Piezoelectric effect on crystals during breakage provide excellent TL properties. • Eu(DBM) 3 DETA can display stress visualization differences of handwriting signatures. Investigation of photoluminescence (PL) and fracture-induced triboluminescence (TL) is necessary for the development of both fundamental theories and practical applications in mechanical energy conversion; however, most known PL/TL-emitting materials are confined to inorganic systems. In this study, a novel lanthanide-based crystalline complex (LnCC), Eu(DBM) 3 DETA was synthesized via the synergistic coordination of Eu3+ with DBM (Dibenzoylmethane) and DETA (Diethylenetriamine) units, leading to the formation of brighter LnCC with bright red emission, high PL quantum yields (57.19 %) and unique TL characteristics. The key to success in obtaining Eu(DBM) 3 DETA is the utilization of DETA molecule as synergistic ligand, presenting block crystals with higher coordination number of Eu3+ ions via recrystallization. Due to the dense accumulation of cross-linked three-dimensional frameworks through van der Waals interactions, the fracture-induced piezoelectric effect results in charge separation and excitation through the resultant electric field and discharge, triggering a fast TL response of Eu(DBM) 3 DETA and expanding the possibilities of the quantitative stress sensing. Importantly, amorphous powders can still recover to their original PL and TL emission intensities after recrystallization in cyclic crystal-to-amorphous phase transitions. The unique PL and TL characteristics of Eu(DBM) 3 DETA provide promising opportunities to display stress visualization differences of electronic signatures under different forces. [ABSTRACT FROM AUTHOR]

Extreme precipitation is a major issue for regional climate, hydrology, and safety of society. Our knowledge of extreme precipitation is poor because of difficulties in gauge observations and biases in regional and global datasets, in particular over the snow dominated regions. Here we investigate and report the distribution and magnitude of under-measured of the maximum daily total precipitation (herein daily maximum precipitation) due to biases in manual gauge observations in the high latitudes (over 45°N), using historical data during 1973–2004. We find remarkable patterns in under-measured of the long-term mean daily maximum precipitation and their association to regional climatic regimes. In contrast to relatively small and large-scale under-measured (<5 mm) of daily maximum rainfall, the biases in daily maximum snowfall are very serious, with the regional high values over 15 mm along the Ural Mountains and the coasts of east Asia, Greenland, in particular northern Eurasia coasts. The frequency distribution of observed daily maximum snowfall underestimate significantly the higher risk events over the high latitudes. Furthermore, defining the phase of extreme precipitation should be cautious over the northern regions, in particular the coasts. These results clearly demonstrate the urgent need to review and update precipitation datasets including recent automatic gauge observations and the knowledge of climate regimes and extremes over the broader northern regions. Unlabelled Image • Serious under-reporting of daily maximum precipitation from manual gauge observations • Remarkable patterns of the under-measured associate to regional climatic regimes • Significant Influences on frequency distribution of daily maximum snowfall and phase of extreme precipitation [ABSTRACT FROM AUTHOR]

A series of M6PS5X (M = Ag, Cu; X = Cl, Br) nonlinear optical (NLO) chalcohalides with special MS3X ligands have been synthesized in this work. Their critical optical performances were systematically measured and the research results show that all of them exhibit strong NLO responses (2.0–2.7 × commercial AgGaS2) and high laser-damage thresholds (1.7–2.3 × AgGaS2), indicating their potential application as good NLO candidates. Furthermore, first-principles calculations were used to study their inherent structure–property relationships and chalcohalides can be expected to be optimal systems for the exploration of new promising IR NLO crystals. [ABSTRACT FROM AUTHOR]

Sulfur nanodots (S-dots), composed of an elemental sulfur core and surface ligands, show unexpected photoluminescence (PL) properties, with the unique features of nontoxicity, hydrophilicity, high stability and easy modification. This review systematically introduces the synthesis methods, characterization, PL mechanisms and some typical applications of S-dots in chemical sensing. As the PL quantum yield (QY) is a key factor to evaluate the performance of luminescent materials, we report the synthesis methods according to the achievement in the promotion of PL QY. The PL mechanisms of S-dots are discussed from the view of the effects of the elemental sulfur core and passivated ligands on the PL QY and emission color. The design principle of analytical methods for various target molecules using S-dots is introduced. We end this review with the conclusions and some challenges in this field, which is expected to provide some clues for researchers in this field. [ABSTRACT FROM AUTHOR]

Objective. Stromal cells and immune cells have important clinical significance in the microenvironment of colorectal cancer (CRC). This study is aimed at developing a CRC gene signature on the basis of stromal and immune scores. Methods. A cohort of CRC patients (n = 433) were adopted from The Cancer Genome Atlas (TCGA) database. Stromal/immune scores were calculated by the ESTIMATE algorithm. Correlation between prognosis/clinical characteristics and stromal/immune scores was assessed. Differentially expressed stromal and immune genes were identified. Their potential functions were annotated by functional enrichment analysis. Cox regression analysis was used to develop an eight-gene risk score model. Its predictive efficacies for 3 years, 5 years, overall survival (OS), and progression-free survival interval (PFI) were evaluated using time-dependent receiver operating characteristic (ROC) curves. The correlation between the risk score and the infiltering levels of six immune cells was analyzed using TIMER. The risk score was validated using an independent dataset. Results. Immune score was in a significant association with prognosis and clinical characteristics of CRC. 736 upregulated and two downregulated stromal and immune genes were identified, which were mainly enriched into immune-related biological processes and pathways. An-eight gene prognostic risk score model was conducted, consisting of CCL22, CD36, CPA3, CPT1C, KCNE4, NFATC1, RASGRP2, and SLC2A3. High risk score indicated a poor prognosis of patients. The area under the ROC curves (AUC) s of the model for 3 years, 5 years, OS, and PFI were 0.71, 0.70, 0.73, and 0.66, respectively. Thus, the model possessed well performance for prediction of patients' prognosis, which was confirmed by an external dataset. Moreover, the risk score was significantly correlated with immune cell infiltration. Conclusion. Our study conducted an immune-related prognostic risk score model, which could provide novel targets for immunotherapy of CRC. [ABSTRACT FROM AUTHOR]

The origins of the Surface Water and Ocean Topography (SWOT) mission date back to the mid-1970s with the launch of GOES-3 and SEASAT. These missions were then followed in 1992 by the Topex-Poseidon satellite, then by Jason-1 (2001), OSTM/Jason-2 (2008), and Jason 3 (2016), a series of joint satellite missions between NASA and CNES with a goal to monitor global ocean circulation. The proposed new SWOT mission will provide 120-km-wide swath interferometric coverage with a 20-km-wide gap at the nadir. The SWOT measurements will consist of water surface elevations and water surface slopes covering nearly all of the earth's land surface at least once every 21 days. In 2010, NASA invited the Canadian Space Agency to contribute, and Canadian scientists welcomed the invitation to join the SWOT Science Definition Team and contribute to the experiments. The Canadian segment of the mission is known as the "SWOT-C" project. The SWOT satellite mission will provide unique opportunities in the Canadian context for water managers in both the public domain and in the private sector. This paper provides an overview of recent scientific progress by the SWOT-C Terrestrial Hydrology team, outlining current plans and progress towards applications and calibration post-launch. [ABSTRACT FROM AUTHOR]

Abstract Long noncoding RNAs (lncRNAs) are characterized as a type of noncoding RNAs over 200 nucleotides with little or none protein-coding potential. In the past years, lncRNAs have been proved to participant in many physiological and pathological processes. However, the role of lncRNAs in colorectal cancer (CRC) still needs more attentions. In our study, we found that lncBRM was highly expressed in CRC samples and the expression level of lncBRM was correlated with metastasis and advanced stage in CRC patients. And also, we showed that high expression of lncBRM predicted poor prognosis. Furthermore, we found that knockdown of lncBRM impaired the proliferation, migration and invasion of CRC cells while overexpressing of lncBRM promotes the proliferation, migration and invasion of CRC cells. Mechanically, we found that lncBRM served as a sponge of miR-204-3p that targeted TPT1. Highly expressed TPT1 can promote the proliferation, migration and invasion of CRC cells. In conclusion, we found that lncBRM was highly expressed in CRC and sponged miR-204-3p to modulate the expression of TPT1. Highlights • LncBRM is highly expressed in CRC tissues and associated with prognosis of CRC patients. • Knockdown of lncBRM impairs the proliferation, migration and invasion of CRC cell. • LncBRM overexpression promotes proliferation, migration and invasion of CRC cells. • LncBRM interacts with miR-204-3p and targets TPT1. [ABSTRACT FROM AUTHOR]

ABSTRACT: In this paper, we investigate the spatiotemporal characteristics and trends of snow cover fraction (SCF) in the Tibetan Plateau (TP) and seven upstream river basins (Yellow, Yangtze, Mekong, Salween, Brahmaputra, Indus and Yarkant) by employing the Moderate Resolution Imaging Spectroradiometer (MODIS) data for 2001–2014. The possible linkage between the SCF, and temperature and precipitation changes over the TP and individual basins is also investigated. Results suggest that the distribution of snow cover over the TP exhibit a large spatiotemporal heterogeneity with high SCFs mainly concentrating on the southern and western edges which is strongly linked to the moist air supplies. The distribution of snow cover is highly dependent on the elevations, with a higher SCF and a later onset of snow melt at the higher elevation zones than at the lowers. There is an elevation threshold existing for separating two distinct snow cover regimes, which are 4000 m for the western basins and 5000 m for the southeastern basins. The snow cover over the TP has slightly decreased by about 1.1% during 2001–2014, with dramatic reductions mostly lying in the heavy snowy regions and some light increases occurring in the areas with annual mean SCFs mostly less than 10%. The reduction rates of snow cover increase with the rising of altitudes for the TP average, and the basins of Indus, Yarkant, Salween and Brahmaputra. At the same time, the Yellow and Yangtze basins exhibit larger increasing rates of snow cover at the higher elevations zones. The SCF variations are linked to the temperature and precipitation changes. Precipitation tends to be the major factor impacting the snow cover changes in the TP during 2001–2014. [ABSTRACT FROM AUTHOR]