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1.
ACS Appl Bio Mater ; 7(5): 3496-3505, 2024 May 20.
Article En | MEDLINE | ID: mdl-38708935

Plant roots are highly sensitive to physical stress in the soil, with appropriate mechanical impedance promoting root elongation and lateral root growth. However, few studies have quantitatively explored the relationship between the mechanical impedance of the growth medium and the phenotypes of plant roots. In this study, we used a tensile machine equipped with a self-made steel needle mimicking the root tip to measure the force needed to penetrate the hydrogel medium (agar, low acyl gellan gum, and κ-carrageenan), providing insights into the force required for the rapeseed root tip to enter the medium following germination. These findings indicate that root penetration length is inversely associated with the mechanical strength of the growth medium, with variations observed in the root system adaptability across different substrates. Specifically, when the gel puncture resistance of the culture medium without adding MS reached approximately 18.4 mN, root penetration and growth were significantly hindered. With the addition of 1/2 MS medium, the polysaccharide concentration is 1.0 wt %, which is more suitable for cultivating rapeseed. This research not only offers a method for quantifying root phenotypes and medium mechanical impedance but also presents an approach for plant growth regulation and crop breeding.


Germination , Hydrogels , Materials Testing , Plant Roots , Polysaccharides , Hydrogels/chemistry , Plant Roots/growth & development , Polysaccharides/chemistry , Brassica rapa/growth & development , Brassica rapa/chemistry , Particle Size , Biocompatible Materials/chemistry
2.
Front Plant Sci ; 13: 904326, 2022.
Article En | MEDLINE | ID: mdl-36212307

Increasing evidence from low-latitude ranges has demonstrated that native parasitic plants are promising biocontrol agents for some major invasive weeds. However, related mechanisms and the effect of environments on the control effect of the parasite are still unclear. In addition, few related studies have been conducted in high latitude (>40°), where the exotic plant richness is the highest in the globe, but natural enemies are relatively scarce. During field surveys, a Cuscuta species was found on the cosmopolitan invasive weed Ambrosia trifida L. in Shenyang, northeast China. Here, we first studied the impacts of the parasite on the invader at three sites with different light regimes and related mechanisms, then the haustorial connections between the parasite and the invader using anatomy and measurement of carbon (C) and nitrogen (N) stable isotope compositions (δ13C, δ15N), and finally identified the parasite using two molecular marks. The parasite was identified as C. japonica Choisy. This native holoparasitic vine posed serious C rather than N limitation to the invader, explaining its greatly inhibitory effects on the invader. Its negative effects were stronger on reproductive relative to vegetative growth, and at high relative to low light habitats, which indicated that the higher the vigor of the host is, the higher the impact of the parasite pose. The parasite could establish haustorial connections with phloem, xylem, and pith of the invader and thus obtain resources from both leaves and roots, which was confirmed by difference of δ13C and δ15N between the two species. The parasite had significantly higher leaf C concentrations and δ13C than its invasive host, being a strong C sink of the parasitic association. Our results indicate that C. japonica may be a promising biological control agent for the noxious invader in China.

3.
BMC Gastroenterol ; 18(1): 104, 2018 Jul 03.
Article En | MEDLINE | ID: mdl-29969994

BACKGROUND: Cyclic vomiting syndrome (CVS) is characterized by repeated, stereotypical vomiting episodes. It is possibly associated with mitochondrial DNA (mtDNA) variants. We examined the phenotype, disease burden, treatment and performed mtDNA analysis in pediatric CVS. METHODS: This retrospective study included 42 children with CVS in a tertiary care center. Information regarding medical history, clinical features, laboratory tests, and treatment were collected. mtDNA sequencing was performed among 13 patients. RESULTS: Mean age of onset among patients was 4.0±3.4 years, and mean age at diagnosis was 6.7±4.2 years. CVS episodes in onset and features were stereotypic. Recognizable prodromes were reported in 54.8% patients. Neuroimaging showed previously unknown intracranial abnormalities. Gastrointestinal infection was found in four patients. Mean duration of hospitalization was 7.0±2.4 days, and mean hospitalization cost was 10,891 RMB. Sequencing showed that 4/13 patients had C16519T mtDNA polymorphism, and 2/13 patients had G3010A mtDNA polymorphism. CONCLUSIONS: Cyclic vomiting syndrome is a disabling disorder, which causes huge disease burdens to the patients and their families. Early clinical suspicion and prompt diagnosis are crucial. mtDNA polymorphisms were found in some patients, but they were not significantly associated with pediatric CVS.


Cost of Illness , DNA, Mitochondrial/genetics , Vomiting/genetics , Vomiting/therapy , Adolescent , Antiemetics/therapeutic use , Child , Child, Preschool , Female , Fluid Therapy , Humans , Male , Ondansetron/therapeutic use , Phenotype , Polymorphism, Genetic , Retrospective Studies , Sequence Analysis, DNA , Vomiting/diagnosis
4.
Acta Crystallogr Sect E Struct Rep Online ; 66(Pt 3): m258, 2010 Feb 06.
Article En | MEDLINE | ID: mdl-21580212

The structure of the title compound, [Zn(C(8)H(4)O(4))(C(6)H(8)N(2))(2)](n), exhibits polymeric zigzag chains extended along the c axis. The Zn(II) ion is coordinated by two N [Zn-N = 2.008 (6) and 2.012 (6) Å] and two O [Zn-O = 1.959 (5) and 1.985 (5) Å] atoms in a distorted tetra-hedral geometry. Weak C-H⋯O inter-actions contribute to the crystal packing stability.

5.
Acta Crystallogr Sect E Struct Rep Online ; 66(Pt 3): m290, 2010 Feb 13.
Article En | MEDLINE | ID: mdl-21580235

The structure of the title compound, [Cd(NCS)(2)(C(5)H(8)N(2))(4)], consists of isolated mol-ecules of [Cd(NCS)(2)(Eim)(4)] (Eim = 1-ethyl-imidazole), which contain a compressed octa-hedral CdN(6) chromophore. The NCS(-) anions are trans and four N atoms from the 1-ethyl-imidazole ligands define the equatorial plane. The mean Cd-N(Eim) and Cd-N(NCS) distances are 2.334 (4) and 2.379 (5) Å, respectively. Weak C-H⋯N inter-actions contribute to the crystal packing stability.

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