In Vitro Regeneration of \u3ci\u3eRudbeckia hirta\u3c/i\u3e ‘Plainview Farm’ from Leaf Tissue

Rudbeckia hirta ‘Plainview Farm’, a new multiple-layered ray flowered cultivar, shows potential for potted plant production. After years of seed germination, this specific flower morphological trait was still unstable from generation to generation. To maintain its unique features, leaf sections (0.25 cm2 ) were cultured on Murashige and Skoog (MS) medium supplemented with either BA (0.5, 1.0, or 2.0 mg·L1 ), KIN (2.5, 5, or 10 mg·L-1 ), or ZT (0.5, 1.0, or 2.0 mg·L-1 )toinduce callus and microshoots. After cultivation for 33 days, all cytokinin treatments significantly induced callus and the callus size were 1.5- to-2.4-fold bigger than those withoutcytokinin. KIN at 2.5 mg·L-1 was the best treatment for callus induction and microshoot formation. Four microshoots per explant wereproduced at KIN of 2.5 mg·L-1 . For rooting, all induced microshoots were cultured on MS medium at its one-quarter strength containing either IBA or NAA at 0.5, 1.5, or 3.0 mg·L-1 . All microshoots formed roots at 0.5 or 1.5 mg·L-1 IBA, or 0.5 mg·L-1 NAA. There were no significant differences in number of roots per shoot and length of roots among treatments. The plantlets were transplanted, acclimated in a mist system, and grown in a greenhouse. A total of 96.4% of the plants derived from tissue culture had multiple layers of ray flowers, while only 9.6% of the plants from seed propagation did. Therefore, in vitro regeneration of R. hirta ‘Plainview Farm’ was a feasible way to rapidly produce uniform plants with multiple layers of ray flowers

Patterned nanofiber air filters with high optical transparency, robust mechanical strength, and effective PM_(2.5) capture capability

PM_(2.5), due to its small particle size, strong activity, ease of the attachment of toxic substances and long residence time in the atmosphere, has a great impact on human health and daily production. In this work, we have presented patterned nanofiber air filters with high optical transparency, robust mechanical strength and effective PM_(2.5) capture capability. Here, to fabricate a transparency air filter by a facile electrospinning method, we chose three kinds of patterned wire meshes with micro-structures as negative receiver substrates and directly electrospun polymer fibers onto the supporting meshes. Compared with randomly oriented nanofibers (named “RO NFs” in this paper) and commercially available facemasks, the patterned air filters showed great mechanical properties, and the water contact angles on their surfaces were about 122–143° (the water contact angle for RO NFs was 81°). In addition, the patterned nanofibers exhibited high porosity (>80%), and their mean pore size was about 0.5838–0.8686 μm (the mean pore size of RO NFs was 0.4374 μm). The results indicate that the transparent patterned air filters have the best PM_(2.5) filtration efficiency of 99.99% at a high transmittance of ∼69% under simulated haze pollution

Patterned nanofiber air filters with high optical transparency, robust mechanical strength, and effective PM_(2.5) capture capability

PM_(2.5), due to its small particle size, strong activity, ease of the attachment of toxic substances and long residence time in the atmosphere, has a great impact on human health and daily production. In this work, we have presented patterned nanofiber air filters with high optical transparency, robust mechanical strength and effective PM_(2.5) capture capability. Here, to fabricate a transparency air filter by a facile electrospinning method, we chose three kinds of patterned wire meshes with micro-structures as negative receiver substrates and directly electrospun polymer fibers onto the supporting meshes. Compared with randomly oriented nanofibers (named “RO NFs” in this paper) and commercially available facemasks, the patterned air filters showed great mechanical properties, and the water contact angles on their surfaces were about 122–143° (the water contact angle for RO NFs was 81°). In addition, the patterned nanofibers exhibited high porosity (>80%), and their mean pore size was about 0.5838–0.8686 μm (the mean pore size of RO NFs was 0.4374 μm). The results indicate that the transparent patterned air filters have the best PM_(2.5) filtration efficiency of 99.99% at a high transmittance of ∼69% under simulated haze pollution

Spontaneous Voltage Oscillations and Response Dynamics of a Hodgkin-Huxley Type Model of Sensory Hair Cells

We employ a Hodgkin-Huxley-type model of basolateral ionic currents in bullfrog saccular hair cells for studying the genesis of spontaneous voltage oscillations and their role in shaping the response of the hair cell to external mechanical stimuli. Consistent with recent experimental reports, we find that the spontaneous dynamics of the model can be categorized using conductance parameters of calciumactivated potassium, inward rectifier potassium, and mechano-electrical transduction (MET) ionic currents. The model is demonstrated for exhibiting a broad spectrumof autonomous rhythmic activity, including periodic and quasi-periodic oscillations with two independent frequencies as well as various regular and chaotic bursting patterns. Complex patterns of spontaneous oscillations in the model emerge at small values of the conductance of Ca2+-activated potassium currents. These patterns are significantly affected by thermal fluctuations of the MET current. We show that selfsustained regular voltage oscillations lead to enhanced and sharply tuned sensitivity of the hair cell to weak mechanical periodic stimuli. While regimes of chaotic oscillations are argued to result in poor tuning to sinusoidal driving, chaotically oscillating cells do provide a high sensitivity to low-frequency variations of external stimuli

Isolation of mouse mammary carcinoma-derived macrophages and cancer cells for co-culture assays

We recently established an in vitro co-culture system in which monophosphoryl lipid A + interferon-γ (MPLA+IFNγ)-treated tumor-associated macrophages (TAMs) killed cancer cells. Here, we describe a step-by-step protocol for isolating TAMs and cancer cells from mouse primary mammary carcinomas, the setup of the co-culture system, and the image acquisition approach. The technical difficulties in the co-culture assay involve isolating pure TAMs and cancer cells from the same tumor and staining them with different dyes to track the macrophages’ tumoricidal activity. For complete details on the use and execution of this protocol, please refer to Sun et al. (2021).(1

Racial/Ethnic Discrimination and Mental Health in Mexican-Origin Youths and Their Parents: Testing the "Linked Lives" Hypothesis

PURPOSE: Using a life course perspective, the present study tested the concept of "linked lives" applied to the problem of not only how racial/ethnic discrimination may be associated with poor mental health for the target of discrimination but also how discrimination may exacerbate the discrimination-distress link for others in the target's social network-in this case, the family. METHODS: The discrimination-distress link was investigated among 269 Mexican-origin adolescents and their parents both cross-sectionally and longitudinally. It was hypothesized that parents' discrimination experiences would adversely affect their adolescent children's mental health via a moderating effect on the target adolescent discrimination-distress link. The converse was also hypothesized for the target parents. Multilevel moderation analyses were conducted to test the moderating effect of parents' discrimination experiences on the youth discrimination-distress link. We also tested the moderating effect of youths' discrimination experiences on the parent discrimination-distress link. RESULTS: Parents' discrimination experiences significantly moderated the longitudinal association between youths' discrimination stress appraisals and mental health, such that the father's discrimination experiences exacerbated the youth discrimination-depression link. Youths' discrimination stress appraisals were not a significant moderator of the cross-sectional parent discrimination-mental health association. CONCLUSIONS: Implications of these findings are discussed from a linked lives perspective, highlighting how fathers' discrimination experiences can adversely affect youths who are coping with discrimination, in terms of their mental health

Automatic thickness estimation for skeletal muscle in ultrasonography: evaluation of two enhancement methods

BACKGROUND: Ultrasonography is a convenient technique to investigate muscle properties and has been widely used to look into muscle functions since it is non-invasive and real-time. Muscle thickness, a quantification which can effectively reflect the muscle activities during muscle contraction, is an important measure for musculoskeletal studies using ultrasonography. The traditional manual operation to read muscle thickness is subjective and time-consuming, therefore a number of studies have focused on the automatic estimation of muscle fascicle orientation and muscle thickness, to which the speckle noises in ultrasound images could be the major obstacle. There have been two popular methods proposed to enhance the hyperechoic regions over the speckles in ultrasonography, namely Gabor Filtering and Multiscale Vessel Enhancement Filtering (MVEF). METHODS: A study on gastrocnemius muscle is conducted to quantitatively evaluate whether and how these two methods could help the automatic estimation of the muscle thickness based on Revoting Hough Transform (RVHT). The muscle thickness results obtained from each of the two methods are compared with the results from manual measurement, respectively. Data from an aged subject with cerebral infarction is also studied. RESULTS: It’s shown in the experiments that, Gabor Filtering and MVEF can both enable RVHT to generate comparable results of muscle thickness to those by manual drawing (mean ± SD, 1.45 ± 0.48 and 1.38 ± 0.56 mm respectively). However, the MVEF method requires much less computation than Gabor Filtering. CONCLUSIONS: Both methods, as preprocessing procedure can enable RVHT the automatic estimation of muscle thickness and MVEF is believed to be a better choice for real-time applications

Molecular Identification and Antifungal Properties of Four Thaumatin-like Proteins in Spruce (Picea likiangensis)

Thaumatin-like proteins (TLPs) are involved in the plant defense response against pathogens, and most of them exhibit antifungal activity. However, the role of TLPs in pathogen-induced defense responses in spruce is not fully understood. In this study, four TLP genes encoding thaumatin-like protein, designated as PlTLP1–4, were isolated and identified from Picea likiangensis needles. Sequence analysis showed that PlTLP1, PlTLP3, and PlTLP4 contained 16 conserved cysteine residues, while PlTLP2 had only 10 conserved cysteine residues. qPCR analysis showed that PlTLPs were expressed in all tissues tested, PlTLP1, PlTLP3, and PlTLP4 had the highest expression levels in young fruits, while PlTLP2 had the highest expression levels in roots. In addition, the expression levels of four PlTLPs were significantly upregulated during infection by Lophodermium piceae. Four recombinant PlTLPs expressed in Escherichia coli exhibited obvious β-1,3-glucanase activity. The antifungal activity assay showed that four recombinant PlTLPs had significant inhibitory effects on the mycelial growth of L. piceae, Fusarium proliferatum, Botrytis cinerea, and Roussoella doimaesalongensis. Microscopic observation revealed that the recombinant PlTLP1–4 induced the morphological changes of the mycelia of L. piceae, and the recombinant PlTLP2 and PlTLP3 induced the morphological changes of the mycelia of F. proliferatum and R. doimaesalongensis, while all the recombinant PlTLPs had no obvious negative effect on the morphology of B. cinerea mycelium. These results suggest that PlTLP genes may play an important role in the defense response of P. likiangensis against L. piceae invasion