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For a given graph G = (V (G), E(G)), a proper total coloring ϕ: V (G) ∪ E(G) → {1, 2, . . . , k} is neighbor sum distinguishing if f(u) ≠ f(v) for each edge uv ∈ E(G), where f(v) = Σuv∈E(G) ϕ(uv)+ϕ(v), v ∈ V (G). The smallest integer k in such a coloring of G is the neighbor sum distinguishing total chromatic number, denoted by χΣ″(G)\chi _\Sigma ^{''} ( G ) . Pilśniak and Woźniak first introduced this coloring and conjectured that χΣ″(G)≤Δ(G)+3\chi _\Sigma ^{''} ( G ) \le \Delta ( G ) + 3 for any graph with maximum degree Δ(G). In this paper, by using the discharging method, we prove that for any planar graph G without 5-cycles, χΣ″(G)≤max{Δ(G)+2, 10}\chi _\Sigma ^{''} ( G ) \le \max \left\{ {\Delta ( G ) + 2,\;10} \right\} . The bound Δ(G) + 2 is sharp. Furthermore, we get the exact value of χΣ″(G)\chi _\Sigma ^{''} ( G ) if Δ(G) ≥ 9.

In the previous paper by the first and the third authors, we present six algorithms for determining whether a given symmetric matrix is strictly copositive, copositive (but not strictly), or not copositive. The algorithms for matrices of order n≥8 are not guaranteed to produce an answer. It also shows that for 1000 symmetric random matrices of order 8, 9, and 10 with unit diagonal and with positive entries all being less than or equal to 1 and negative entries all being greater than or equal to −1, there are 8, 6, and 2 matrices remaing undetermined, respectively. In this paper we give two more algorithms for n=8,9 and our experiment shows that no such matrix of order 8 or 9 remains undetermined; and almost always no such matrix of order 10 remains undetermined. We also do some discussion based on our experimental results.

Abstract Background The extracellular calcium-sensing receptor (CaSR) belongs to family C of the G protein coupled receptors. Whether the CaSR is expressed in the pulmonary artery (PA) is unknown. Methods The expression and distribution of CaSR were detected by RT-PCR, Western blotting and immunofluorescence. PA tension was detected by the pulmonary arterial ring technique, and the intracellular calcium concentration ([Ca2+]i) was detected by a laser-scanning confocal microscope. Results The expressions of CaSR mRNA and protein were found in both rat pulmonary artery smooth muscle cells (PASMCs) and PAs. Increased levels of [Ca2+]o (extracellular calcium concentration) or Gd3+ (an agonist of CaSR) induced an increase of [Ca2+]i and PAs constriction in a concentration-dependent manner. In addition, the above-mentioned effects of Ca2+ and Gd3+ were inhibited by U73122 (specific inhibitor of PLC), 2-APB (specific antagonist of IP3 receptor), and thapsigargin (blocker of sarcoplasmic reticulum calcium ATPase). Conclusions CaSR is expressed in rat PASMCs, and is involved in regulation of PA tension by increasing [Ca2+]i through G-PLC-IP3 pathway.

Abstract Background Myocardial ischemia/reperfusion injury is the major cause of morbidity and mortality for cardiovascular diseases. Dopamine D2 receptors are expressed in cardiac tissues. However, the roles of dopamine D2 receptors in myocardial ischemia/reperfusion injury and cardiomyocyte apoptosis are unclear. Here we investigated the effects of both dopamine D2 receptors agonist (bromocriptine) and antagonist (haloperidol) on apoptosis of cultured neonatal rat ventricular myocytes induced by ischemia/reperfusion injury. Methods Myocardial ischemia/reperfusion injury was simulated by incubating primarily cultured neonatal rat cardiomyocytes in ischemic (hypoxic) buffer solution for 2 h. Thereafter, these cells were incubated for 24 h in normal culture medium. Results Treatment of the cardiomyocytes with 10 μM bromocriptine significantly decreased lactate dehydrogenase activity, increased superoxide dismutase activity, and decreased malondialdehyde content in the culture medium. Bromocriptine significantly inhibited the release of cytochrome c, accumulation of [Ca2+]i, and apoptosis induced by ischemia/reperfusion injury. Bromocriptine also down-regulated the expression of caspase-3 and -9, Fas and Fas ligand, and up-regulated Bcl-2 expression. In contrast, haloperidol (10 μM) had no significant effects on the apoptosis of cultured cardiomyocytes under the aforementioned conditions. Conclusions These data suggest that activation of dopamine D2 receptors can inhibit apoptosis of cardiomyocytes encountered during ischemia/reperfusion damage through various pathways.

Abstract Communication between the SR (sarcoplasmic reticulum, SR) and mitochondria is important for cell survival and apoptosis. The SR supplies Ca2+ directly to mitochondria via inositol 1,4,5-trisphosphate receptors (IP3Rs) at close contacts between the two organelles referred to as mitochondrion-associated ER membrane (MAM). Although it has been demonstrated that CaR (calcium sensing receptor) activation is involved in intracellular calcium overload during hypoxia/reoxygenation (H/Re), the role of CaR activation in the cardiomyocyte apoptotic pathway remains unclear. We postulated that CaR activation plays a role in the regulation of SR-mitochondrial inter-organelle Ca2+ signaling, causing apoptosis during H/Re. To investigate the above hypothesis, cultured cardiomyocytes were subjected to H/Re. We examined the distribution of IP3Rs in cardiomyocytes via immunofluorescence and Western blotting and found that type 3 IP3Rs were located in the SR. [Ca2+]i, [Ca2+]m and [Ca2+]SR were determined using Fluo-4, x-rhod-1 and Fluo 5N, respectively, and the mitochondrial membrane potential was detected with JC-1 during reoxygenation using laser confocal microscopy. We found that activation of CaR reduced [Ca2+]SR, increased [Ca2+]i and [Ca2+]m and decreased the mitochondrial membrane potential during reoxygenation. We found that the activation of CaR caused the cleavage of BAP31, thus generating the pro-apoptotic p20 fragment, which induced the release of cytochrome c from mitochondria and the translocation of bak/bax to mitochondria. Taken together, these results reveal that CaR activation causes Ca2+ release from the SR into the mitochondria through IP3Rs and induces cardiomyocyte apoptosis during hypoxia/reoxygenation.

This study presents a compact intracavity difference-frequency generation (DFG) source designed for mid-infrared (mid-IR) applications. By optimizing overlap between the pump and signal beams, we obtained a black-box efficiency ( η B B ) of 3.4% W⁻1 and a maximum DFG output power of 63 mW at a wavelength of 3437 nm for a 50 mm long periodically poled lithium niobate (PPLN) crystal. The mid-IR laser was systematically studied for various PPLN lengths (29 mm, 40 mm, and 50 mm), demonstrating extensive tunability across a range of mid-IR wavelengths. Stability assessments over short-term (2 min) and long-term (2 h) periods were also investigated, showing stability values of 0.91% and 1.08%, respectively. These advancements position our DFG laser as a promising candidate for potential applications in greenhouse gas detection and satellite communication, addressing the growing demand for reliable and efficient mid-IR sources. [ABSTRACT FROM AUTHOR]

In this paper, we report a new model for passively Q-switched intracavity optical parametric oscillators (IC-OPOs), using Cr:YAG as a Q-switch crystal. The model considers the effects of thermalization in the Nd:YAG laser crystal, excited state absorption in the Cr:YAG saturable absorber, nonlinear loss due to pump depletion in the nonlinear crystal, the thermal lens effect and the mode overlap of the fields within the nonlinear crystal. The calculated pulse width for the 1,064 nm pump light was 6.2 ns compared to the experimental result of 6 ns, while the signal wave was calculated to have a pulse width of 1.75 ns compared to the experimental result of 2 ns. The model is shown to accurately calculate both the temporal and output power characteristics of the IC-OPO, which has not been previously reported to the best of our knowledge. [ABSTRACT FROM AUTHOR]

[Objectives] To investigate the ovarian development and timing of oviposition in the Goji fruit fly, Neoceratitis asiatica (Becker), an important pest of Lycium barbarum L, and thereby identify the critical period for controlling this pest in the field. [Methods] Females were dissected under a microscope 1 to 45 days after their emergence and the length and width of their ovaries, and the number of mature eggs, were recorded. In addition, the number of eggs laid on young fruits within 45 days of emergence was recorded to determine the timing of oviposition. [Results] Ovarian development could be divided into five stages; the early stage (I), the egg-maturing stage (II), the early oviparous stage (III), the peak oviparous stage (IV), and the late oviparous stage (V). Females became sexually mature on the fourth day after eclosion and those that had mated began laying eggs on the same day. [Conclusion] The fourth day after the emergence of female N. asiatica is the critical time for controlling this pest in the field. [ABSTRACT FROM AUTHOR]

The eutrophication of aquatic ecosystems caused by rapid human urbanization has led to an increased production of potentially hazardous bacterial populations, known as blooms. One of the most notorious forms of these aquatic blooms are cyanobacteria, which in sufficiently large quantities can pose a hazard to human health through ingestion or prolonged exposure. Currently, one of the greatest difficulties in regulating and monitoring these potential hazards is the early detection of cyanobacterial blooms, in real time. Therefore, this paper presents an integrated microflow cytometry platform for label-free phycocyanin fluorescence detection, which can be used for the rapid quantification of low-level cyanobacteria and provide early warning alerts for potential harmful cyanobacterial blooms. An automated cyanobacterial concentration and recovery system (ACCRS) was developed and optimized to reduce the assay volume, from 1000 mL to 1 mL, to act as a pre-concentrator and subsequently enhance the detection limit. The microflow cytometry platform utilizes an on-chip laser-facilitated detection to measure the in vivo fluorescence emitted from each individual cyanobacterial cell, as opposed to measuring overall fluorescence of the whole sample, potentially decreasing the detection limit. By applying transit time and amplitude thresholds, the proposed cyanobacteria detection method was verified by the traditional cell counting technique using a hemocytometer with an R2 value of 0.993. It was shown that the limit of quantification of this microflow cytometry platform can be as low as 5 cells/mL for Microcystis aeruginosa, 400-fold lower than the Alert Level 1 (2000 cells/mL) set by the World Health Organization (WHO). Furthermore, the decreased detection limit may facilitate the future characterization of cyanobacterial bloom formation to better provide authorities with ample time to take the appropriate actions to mitigate human risk from these potentially hazardous blooms. [ABSTRACT FROM AUTHOR]

[Objectives] To investigate the oviposition preferences of gall midge, Gephyraulus lycantha Jiao & Kolesik (Diptera: Cecidomyiidae), females with respect to three different Lycium spp. host plants, and thereby clarify the effect of semiochemicals on host selection. [Methods] Oviposition preferences for three host plants, L. barbarum, L. chinense and L. ruthenicum, were determined in both choice and no-choice experiments. The preference of gravid females for specific volatiles emitted from these three different host plant species was measured in a Y-tube olfactometer under laboratory conditions. Dynamic headspace collection and gas chromatography-mass spectrometry were used to analyze differences in the composition of volatiles emitted from the three different host plant species. [Results] L. barbarum was the preferred host species with a significantly (P<0.05) higher oviposition selection rate and number of eggs laid on the young flower buds of this species than on L. chinense or L. ruthenicum. The results of Y-tube olfactory experiments showed that females also significantly (P<0.05) preferred volatiles from bud-bearing branches of L. barbarum to those of the other two species. There were significant differences in the volatiles emitted from healthy flower buds of the three Lycium species. Volatile components of L. barbarum and L. chinense were relatively similar in that both contain a higher proportion of esters, whereas L. ruthenicum volatiles were low in esters and high in ketones. [Conclusion] G. lycantha significantly preferred ovipositing on L. barbarum to L. chinense or L. ruthenicum. Differences in the volatiles emitted from flower buds of L. barbarum might be responsible for this preference. [ABSTRACT FROM AUTHOR]