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1.
J Am Chem Soc ; 144(10): 4294-4299, 2022 03 16.
Artículo en Inglés | MEDLINE | ID: mdl-35119845

RESUMEN

Structural regulation of the active centers is often pivotal in controlling the catalytic functions, especially in iron-based oxidation systems. Here, we discovered a significantly altered catalytic oxidation pathway via a simple cation intercalation into a layered iron oxychloride (FeOCl) scaffold. Upon intercalation of FeOCl with potassium iodide (KI), a new stable phase of K+-intercalated FeOCl (K-FeOCl) was formed with slided layers, distorted coordination, and formed high-spin Fe(II) species compared to the pristine FeOCl precursor. This structural manipulation steers the catalytic H2O2 activation from a traditional Fenton-like pathway on FeOCl to a nonradical ferryl (Fe(IV)═O) pathway. Consequently, the K-FeOCl catalyst can efficiently remove various organic pollutants with almost 2 orders of magnitude faster reaction kinetics than other Fe-based materials via an oxidative coupling or polymerization pathway. A reaction-filtration coupled process based on K-FeOCl was finally demonstrated and could potentially reduce the energy consumption by almost 50%, holding great promise in sustainable pollutant removal technologies.


Asunto(s)
Contaminantes Ambientales , Compuestos de Hierro , Peróxido de Hidrógeno , Hierro , Compuestos de Hierro/química , Oxidación-Reducción , Potasio
2.
PLoS One ; 19(8): e0308166, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-39116075

RESUMEN

OBJECTIVE: Sinus membrane perforation is a common complication of sinus lift surgery. This review aimed to examine if anatomical factors such as the presence of septa and lateral wall thickness influence the risk of membrane perforation. METHODS: This study was registered on PROSPERO (CRD42023488259). PubMed, Embase, and Web of Science were searched for relevant studies published up to 26th June 2024. The outcome of interest was the risk of perforation based on presence of septa and lateral wall thickness. Random-effects meta-analysis was conducted with dichotomous data to obtain the odds ratio (OR) of perforation using Review Manager. RESULTS: Ten studies with 1865 patients undergoing 2168 "lateral" sinus lift procedures were included. The total incidence of Schneiderian membrane perforations was 19% (405 cases). Schneiderian membrane perforation was present in 169/425 cases (39.76%) with sinus septa and 184/1492 cases (12.33%) without septa. Meta-analysis showed that septa were significantly associated with an increased risk of perforation (OR: 4.03 95% CI: 1.77, 9.19) with high heterogeneity (I2 = 87%). The certainty of the evidence was very low. Data on lateral wall thickness and risk of perforation was too heterogeneous for a meta-analysis. Studies reported mixed results on the risk of perforation based on lateral wall thickness. CONCLUSIONS: Our results show, with very low-quality evidence, that the presence of septa significantly increases the risk of perforations during maxillary sinus lift surgery. Evidence on the association between lateral wall thickness and a risk of perforations during sinus lift surgery is conflicting, and no clear conclusions can be derived at this stage.


Asunto(s)
Seno Maxilar , Humanos , Seno Maxilar/cirugía , Seno Maxilar/diagnóstico por imagen , Elevación del Piso del Seno Maxilar/efectos adversos , Factores de Riesgo , Mucosa Nasal/lesiones
3.
Chem Sci ; 2024 Aug 23.
Artículo en Inglés | MEDLINE | ID: mdl-39239481

RESUMEN

Herein we demonstrate that the rapid 'shapeshifting' constitutional isomerization of a substituted bullvalene is influenced by the E-to-Z configurational isomerization of a remote carbamate group, giving rise to correlated motion. We find that, while the E-configurational isomer of a bulky carbamate favors the ß-bullvalene constitutional isomer, a noncovalent bonding interaction within the Z-carbamate tips the equilibrium toward the γ-bullvalene form. Using DFT modelling and NMR spectroscopy, this long-range interaction is identified as being between the bullvalene core and a pendant phenyl group connected to the carbamate. Coupling the constitutional changes of a bullvalene to a reciprocal configurational isomerization through a long-range interaction in this way will allow shapeshifting rearrangements to be exploited as part of collective motion in extended structures.

4.
PeerJ ; 6: e4513, 2018.
Artículo en Inglés | MEDLINE | ID: mdl-29576978

RESUMEN

The escaping behavior of termites has been documented under laboratory conditions; however, no study has been conducted in a field setting due to the difficulty of observing natural behaviors inside wood or structures (e.g., nests, tunnels, etc.). The black-winged termite, Odontotermes formosanus (Shiraki), is a subterranean macrotermitine species which builds extensive mud tubes on tree trunks. In the present study, 41 videos (totaling ∼2,700 min) were taken on 22 colonies/subcolonies of O. formosanus after their mud tubes were partially damaged by hand. In general, termites consistently demonstrated three phases of escape, including initiation (wandering near the mud-tube breach), individual escaping (single termites moving downward), and massive, unidirectional escaping flows (groups of termites moving downward). Downward moving and repairing were the dominant behavioral activities of individuals and were significantly more frequent than upward moving, turning/backward moving, or wandering. Interestingly, termites in escaping flows moved significantly faster than escaping individuals. Repairing behavior was observed shortly after the disturbance, and new mud tubes were preferentially constructed from the bottom up. When predators (i.e., ants) were present, however, termites stopped moving and quickly sealed the mud-tube openings by capping the broken ends. Our study provides an interesting example that documents an animal (besides humans) simultaneously carrying out pathway repairs and emergency evacuation without congestion.

5.
Insect Sci ; 25(3): 499-507, 2018 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-28028926

RESUMEN

Many previous studies have focused on the foraging behaviors and strategies of the red imported fire ants, Solenopsis invicta Buren on solid food or granular bait; little attention has been paid to how liquid sugar is fed upon. In the present study, behavioral responses of S. invicta to 25% sucrose water droplets were observed. Five foraging patterns were identified in S. invicta colonies under laboratory conditions: (i) no feeding, no sucrose water feeding was observed; (ii) surround feeding, ants surrounded and fed along the edge of the sucrose droplet; (iii) stacked feeding, ants stacked and fed along the edge of the sucrose droplet; (iv) droplet-break feeding, ants broke the liquid droplet and sucked sucrose water that spread on surface of the substance or soil particles previously transported by ants; and (v) cover feeding, whole surface of the sucrose droplet was covered by layers of feeding ants. This is the first time cover feeding in S. invicta has been reported, which obviously requires more ants compared to the other patterns. In addition, individual ants were tracked in videos under laboratory conditions, and behavioral repertoires that led to stacking, covering and droplet-breaking were identified and described. The field investigation showed that surround feeding was most frequently performed by S. invicta foragers; however, cover feeding was not observed under field conditions during this study. Both laboratory and field studies showed colony-level variations in sugar-water feeding.


Asunto(s)
Hormigas , Conducta Alimentaria , Animales , Sacarosa
6.
Environ Entomol ; 46(6): 1365-1373, 2017 12 08.
Artículo en Inglés | MEDLINE | ID: mdl-29069472

RESUMEN

Ectropis grisescens Warren (Lepidoptera: Geometridae) is one of the most severe pests of tea plants in China. This species commonly pupates in soil; however, little is known about its pupation ecology. In the present study, choice and no-choice tests were conducted to investigate the pupation behaviors and emergence success of E. grisescens in response to different substrates (sand, sandy loam 1, sandy loam 2, and silt loam) and moisture contents (5, 20, 35, 50, 65, and 80%). Moisture-choice bioassays showed that significantly more E. grisescens individuals pupated in or on soil (sandy loam 1 and 2 and silt loam) that was at the intermediate moisture levels, whereas 5%- and 35%-moisture sand was significantly more preferred over 80%-moisture sand for pupating. Substrate-choice bioassays showed that sand was most preferred by E. grisescens individuals at 20%- and 80%-moisture levels, but no preference was detected among the four substrates at 50%-moisture content. No-choice tests showed that the percentage of burrowed E. grisescens individuals and pupation depth were significantly lower when soil was dry (20% moisture) or wet (80% moisture). In addition, 20%-moisture sandy loam 2 and silt loam significantly decreased the body water content of pupae and emergence success of adults compared to 50%-moisture content. However, each measurement (percentage of burrowed individuals, pupation depth, body water content, or emergence success) was similar when compared among different moisture levels of sand. Interestingly, pupae buried with 80%-moisture soil exhibited significantly lower emergence success than that were unburied.


Asunto(s)
Mariposas Nocturnas/crecimiento & desarrollo , Suelo/química , Agua/análisis , Animales , China , Pupa/crecimiento & desarrollo
7.
J Econ Entomol ; 109(4): 1827-33, 2016 08.
Artículo en Inglés | MEDLINE | ID: mdl-27298425

RESUMEN

In the present study, the repellent effects of essential balm, a traditional medicine product in China, was tested against foraging and defending red imported fire ants, Solenopsis invicta Buren, under laboratory and field conditions. The laboratory study showed that both band- (width = 1 cm) and patch-smearing of essential balm at each concentration (0.5, 1, or 2 µl/cm(2)) significantly decreased the number of S. invicta foragers within the 6-h observation period. Moreover, band-smearing of 2 µl/cm(2) essential balm and patch-smearing of 0.5, 1, and 2 µl/cm(2) essential balm inhibited most S. invicta foraging activity at 3, 6, 6, and 24 h into the experiment, respectively. The field study showed that after a disturbance was created on the S. invicta mound, there were significantly less defending ants on the substance treated (patch-smeared) with 0.5, 1, and 2 µl/cm(2) essential balm than the controls, but the number of ants on the substance of these three concentrations was similar. Our study suggested that essential balm is a strong repellent against foraging and defending S. invicta and could be applied when temporary protection from S. invicta is needed.


Asunto(s)
Hormigas , Control de Insectos , Repelentes de Insectos , Aceites Volátiles , Animales , Medicina Tradicional China
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