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Wild waterfowl serve as a reservoir of some astroviruses. Fecal samples from wild waterfowl collected at Hong Kong's Marshes were tested using pan-astrovirus reverse transcription-PCR. Positive samples underwent subsequent host identification using DNA barcoding. Based on deduced partial sequences, noteworthy samples from three astrovirus groups (mammalian, avian and unclassified astroviruses) were further analyzed by next-generation sequencing. One sample of Avastrovirus 4 clade, MP22-196, had a nearly complete genome identified. The results of ORF2 phylogenetic analysis and genetic distance analysis indicate that Avastrovirus 4 is classified as a distinct subclade within Avastrovirus. MP22-196 has typical astrovirus genome characteristics. The unique characteristics and potential differences of this genome, compared to other avian astrovirus sequences, involve the identification of a modified sgRNA sequence situated near the ORF2 start codon, which precedes the ORF1b stop codon. Additionally, the 3' UTR of MP22-196 is shorter than other avian astroviruses. This study expands our understanding of the Avastrovirus 4 clade.
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Infecciones por Astroviridae , Aves , Heces , Variación Genética , Genoma Viral , Filogenia , Animales , Hong Kong , Aves/virología , Heces/virología , Infecciones por Astroviridae/veterinaria , Infecciones por Astroviridae/virología , Animales Salvajes/virología , Enfermedades de las Aves/virología , Secuenciación de Nucleótidos de Alto Rendimiento , Avastrovirus/genética , Avastrovirus/clasificación , Avastrovirus/aislamiento & purificación , ARN Viral/genética , Sistemas de Lectura Abierta , Astroviridae/genética , Astroviridae/aislamiento & purificación , Astroviridae/clasificaciónRESUMEN
To test the hypothesis that an abiotic Earth and its inert atmosphere could form chemically reactive carbon- and nitrogen-containing compounds, we designed a plasma electrochemical setup to mimic lightning-induced electrochemistry under steady-state conditions of the early Earth. Air-gap electrochemical reactions at air-water-ground interfaces lead to remarkable yields, with up to 40 moles of carbon dioxide being reduced into carbon monoxide and formic acid, and 3 moles of gaseous nitrogen being fixed into nitrate, nitrite, and ammonium ions, per mole of transmitted electrons. Interfaces enable reactants (e.g., minerals) that may have been on land, in lakes, and in oceans to participate in radical and redox reactions, leading to higher yields compared to gas-phase-only reactions. Cloud-to-ground lightning strikes could have generated high concentrations of reactive molecules locally, establishing diverse feedstocks for early life to emerge and survive globally.
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OBJECTIVES: Currently, premixed putty-type bioceramic cements (PPBCs) have become popular materials for root-end fillings. This study investigated three root-end filling techniques using PPBCs and calcium silicate-based sealers including EDTA pretreatment. MATERIALS AND METHODS: Ninety root segments were prepared and standardized with an artificial fin and lateral canal, and assigned to three groups (n = 30). Root-end fillings were placed using BC-RRM Putty alone (Group PA), injection of BC sealer followed by BC-RRM Putty (Lid Technique: Group LT) or BC-RRM Putty with BC sealer coating (Deep putty packing technique: Group DP). Half of each group was pretreated with 17% EDTA. The radiographic images of the specimens were assessed by five graders and push-out bond strength tests were conducted. The data were analyzed with a general linear model including two-way ANOVA and chi-square test at a significance level of 5%. RESULTS: DP approach demonstrated significantly higher bond strength than LT (P < 0.05). However, there was no statistically significant difference in bond strength between PA and either DP or LT. EDTA pretreatment had no significant effect on push-out bond strength. Radiographically, for the main canal, PA and DP scored significantly higher than LT. In the fin, PA scored significantly higher than others (P < 0.05). CONCLUSION: Our study highlights variations in root-end filling techniques. Injecting a bulk of bioceramic sealer before the placement of PPBCs may reduce bond strength and radiopacity. The application of PPBCs alone or in the deep putty technique demonstrates potential for favorable outcomes. EDTA pretreatment did not enhance bond-strength. CLINICAL RELEVANCE: Careful selection and application of bioceramic materials and techniques in root-end fillings may influence the outcome of endodontic root-end surgery. When PPBCs and calcium silicate-based sealers are used together for root-end fillings, sealer followed by deep putty application may offer improved bond strength and radiographic fill compared to the lid technique.
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Compuestos de Calcio , Ensayo de Materiales , Materiales de Obturación del Conducto Radicular , Silicatos , Materiales de Obturación del Conducto Radicular/química , Silicatos/química , Compuestos de Calcio/química , Técnicas In Vitro , Humanos , Recubrimiento Dental Adhesivo/métodos , Cerámica/química , Cementos Dentales/química , Obturación Retrógrada/métodos , Ácido Edético/química , Análisis del Estrés DentalRESUMEN
The cardinal symptoms of Parkinson's disease (PD) such as bradykinesia and akinesia are debilitating, and treatment options remain inadequate. The loss of nigrostriatal dopamine neurons in PD produces motor symptoms by shifting the balance of striatal output from the direct (go) to indirect (no-go) pathway in large part through changes in the excitatory connections and intrinsic excitabilities of the striatal projection neurons (SPNs). Here, we report using two different experimental models that a transient increase in striatal dopamine and enhanced D1 receptor activation, during 6-OHDA dopamine depletion, prevent the loss of mature spines and dendritic arbors on direct pathway projection neurons (dSPNs) and normal motor behavior for up to 5 months. The primary motor cortex and midline thalamic nuclei provide the major excitatory connections to SPNs. Using ChR2-assisted circuit mapping to measure inputs from motor cortex M1 to dorsolateral dSPNs, we observed a dramatic reduction in both experimental model mice and controls following dopamine depletion. Changes in the intrinsic excitabilities of SPNs were also similar to controls following dopamine depletion. Future work will examine thalamic connections to dSPNs. The findings reported here reveal previously unappreciated plasticity mechanisms within the basal ganglia that can be leveraged to treat the motor symptoms of PD.
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Photoactivated catalysts for the hydrosilylation of alkenes with silanes offer temporal control in manufacturing processes that require silicone curing. We report the development of a range of air-stable Pt(II) (salicylaldimine)(phenylpyridyl), [Pt(sal)(ppy)], complexes as photoinitiated hydrosilylation catalysts. Some of these catalysts show appreciable latency in thermal catalysis and can also be rapidly (10 s) activated by a LED UV-light source (365 nm), to give systems that selectively couple trimethylvinylsilane and hexamethylsiloxymethylsilane to give the linear hydrosilylation product. Although an undetectable (by NMR spectroscopy) amount of precatalyst is converted to the active form under UV-irradiation in the timescale required to initiate hydrosilylation, clean and reliable kinetics can be measured for these systems that allow for a detailed mechanism to be developed for Pt(sal)(ppy)-based photoactivated hydrosilylation. The suggested mechanism is shown to have close parallels with, but also subtle differences from, those previously proposed for thermally-activated Karstedt-type Pt(0) systems.
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Agricultural insect pests (AIPs) are widely successful in adapting to natural and anthropogenic stressors, repeatedly overcoming population bottlenecks and acquiring resistance to intensive management practices. Although they have been largely overlooked in evolutionary studies, AIPs are ideal systems for understanding rapid adaptation under novel environmental conditions. Researchers have identified several genomic mechanisms that likely contribute to adaptive stress responses, including positive selection on de novo mutations, polygenic selection on standing allelic variation and phenotypic plasticity (e.g., hormesis). However, new theory suggests that stress itself may induce epigenetic modifications, which may confer heritable physiological changes (i.e., stress-resistant phenotypes). In this perspective, we discuss how environmental stress from agricultural management generates the epigenetic and genetic modifications that are associated with rapid adaptation in AIPs. We summarise existing evidence for stress-induced evolutionary processes in the context of insecticide resistance. Ultimately, we propose that studying AIPs offers new opportunities and resources for advancing our knowledge of stress-induced evolution.
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Bovine familial convulsions and ataxia (BFCA) is considered an autosomal dominant syndrome with incomplete penetrance. Nine Angus calves from the same herd were diagnosed with BFCA within days of birth. Necropsy revealed cerebellar and spinal cord lesions associated with the condition. Parentage testing confirmed that all affected calves had a common sire. The sire was then bred to 36 cows across two herds using artificial insemination, producing an additional 14 affected calves. The objective of this investigation was to identify hypothesized dominant genetic variation underlying the condition. Whole-genome sequencing was performed on the sire, six affected and seven unaffected paternal half-sibling calves and combined with data from 135 unrelated controls. The sire and five of the six affected calves were heterozygous for a nonsense variant (Chr7 g.12367906C>T, c.5073C>T, p.Arg1681*) in CACNA1A. The other affected calves (N = 8) were heterozygous for the variant but it was absent in the other unaffected calves (N = 7) and parents of the sire. This variant was also absent in sequence data from over 6500 other cattle obtained via public repositories and collaborator projects. The variant in CACNA1A is expressed in the cerebellum of the ataxic calves as detected in the transcriptome and was not differentially expressed compared with controls. The CACNA1A protein is part of a highly expressed cerebellar calcium voltage gated channel. The nonsense variant is proposed to cause haploinsufficiency, preventing proper transmission of neuronal signals through the channel and resulting in BFCA.
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Ataxia , Canales de Calcio , Enfermedades de los Bovinos , Convulsiones , Animales , Bovinos/genética , Canales de Calcio/genética , Ataxia/veterinaria , Ataxia/genética , Enfermedades de los Bovinos/genética , Convulsiones/veterinaria , Convulsiones/genética , Masculino , Femenino , Secuenciación Completa del Genoma/veterinaria , Genes Dominantes , MutaciónRESUMEN
Numerous modern technologies are reliant on the low-phase noise and exquisite timing stability of microwave signals. Substantial progress has been made in the field of microwave photonics, whereby low-noise microwave signals are generated by the down-conversion of ultrastable optical references using a frequency comb1-3. Such systems, however, are constructed with bulk or fibre optics and are difficult to further reduce in size and power consumption. In this work we address this challenge by leveraging advances in integrated photonics to demonstrate low-noise microwave generation via two-point optical frequency division4,5. Narrow-linewidth self-injection-locked integrated lasers6,7 are stabilized to a miniature Fabry-Pérot cavity8, and the frequency gap between the lasers is divided with an efficient dark soliton frequency comb9. The stabilized output of the microcomb is photodetected to produce a microwave signal at 20 GHz with phase noise of -96 dBc Hz-1 at 100 Hz offset frequency that decreases to -135 dBc Hz-1 at 10 kHz offset-values that are unprecedented for an integrated photonic system. All photonic components can be heterogeneously integrated on a single chip, providing a significant advance for the application of photonics to high-precision navigation, communication and timing systems.
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This research addresses the long-standing debate about the determinants of sex/gender differences. Evolutionary theorists trace many sex/gender differences back to natural selection and sex-specific adaptations. Sociocultural and biosocial theorists, in contrast, emphasize how societal roles and social power contribute to sex/gender differences beyond any biological distinctions. By connecting two empirical advances over the past two decades-6-fold increases in sex/gender difference meta-analyses and in experiments conducted on the psychological effects of power-the current research offers a novel empirical examination of whether power differences play an explanatory role in sex/gender differences. Our analyses assessed whether experimental manipulations of power and sex/gender differences produce similar psychological and behavioral effects. We first identified 59 findings from published experiments on power. We then conducted a P-curve of the experimental power literature and established that it contained evidential value. We next subsumed these effects of power into 11 broad categories and compared them to 102 similar meta-analytic sex/gender differences. We found that high-power individuals and men generally display higher agency, lower communion, more positive self-evaluations, and similar cognitive processes. Overall, 71% (72/102) of the sex/gender differences were consistent with the effects of experimental power differences, whereas only 8% (8/102) were opposite, representing a 9:1 ratio of consistent-to-inconsistent effects. We also tested for discriminant validity by analyzing whether power corresponds more strongly to sex/gender differences than extraversion: although extraversion correlates with power, it has different relationships with sex/gender differences. These results offer novel evidence that many sex/gender differences may be explained, in part, by power differences.
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Single-photon avalanche diodes (SPADs) that are sensitive to photons in the Short-wave infrared and extended short-wave infrared (SWIR and eSWIR) spectra are important components for communication, ranging, and low-light level imaging. The high gain, low excess noise factor, and widely tunable bandgap of AlxIn1-xAsySb1-y avalanche photodiodes (APDs) make them a suitable candidate for these applications. In this work, we report single-photon-counting results for a separate absorption, charge, and multiplication (SACM) Geiger-mode SPAD within a gated-quenching circuit. The single-photon avalanche probabilities surpass 80% at 80â K, corresponding with single-photon detection efficiencies of 33% and 12% at 1.55 µm and 2 µm, respectively.
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Physical evaluation of beef bulls is important in determining their ability to be long-lived useful breeding animals. A basic examination should include an assessment of the bull's conformation, gait, and overall appearance. Skeletal soundness can be easily evaluated with well-formed feet and legs. Muscularity and reproductive soundness can be verified visually as should the head and mouth. Finally, attention should be paid to breed characteristics if it is a purebred bull. A bull must be able to walk, eat, and see to effectively function as a natural service sire in pasture, pens, or especially extensive range environments.
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Reproducción , Bovinos , Animales , MasculinoRESUMEN
Lytic lesions from bone metastases from breast, lung and prostate carcinomas, are associated with a poor prognosis and significant morbidities that include fracture and debilitating pain. Chemotherapeutics, palliative radiation therapy and surgical intervention are routinely used to treat these lesions. The ZetaMet™ Bone Graft is a novel antitumorigenic and osteoinductive graft that offers a potential alternative treatment option. ZetaMet is composed of calcium phosphate salts, type-I collagen and the small molecule N-allyl noroxymorphone dihydrate. Here, we report the case of a stage IV breast cancer patient with multiple lytic metastatic lesions to the spine that were successfully treated, which led to a significant reduction in pain and increased quality of life. This outcome demonstrates that a locally administered therapeutic intervention may represent an important alternative for patients with bone metastases that warrants further study.
What questions did we seek to answer? Pain from bone cancer is debilitating, uncurable and often treated with opioid drugs that reduce a person's quality of life. A recently discovered drug might help patients by preventing bone pain by making new bone while stopping bone destruction caused by the tumor. A patient with stage IV breast cancer, who was in immense pain and could no longer be active, underwent treatment. She had widely distributed metastases from the breast cancer in her liver, lungs, brain and bones. The tumors had traveled to her spine causing immense pain, and she requested treatment with the experimental drug/device ZetaMet™. Via special permission from the US FDA, the patient received the experimental treatment, which has not been approved for use. After FDA approval for the experimental use of ZetaMet, tumors in three bones of the patient's spine were treated. What were the results? 2 years after treatments with ZetaMet for the tumors located in three different spinal bones, the patient is alive, and her pain has become manageable, leading to quality-of-life improvements and resumption of many routine daily activities, such as walking and spending time with family, despite the typical prognosis for this type of cancer (survival <6 months). Further, the treatment led the patient to electively reduce pain medication use by over fourfold, which decreases the serious risks and many complications posed by overuse. What do the results suggest? The experimental treatment, ZetaMet, has a great deal of promise in treating very sick patients with breast cancer that has spread to bone, improving quality of life and reducing pain medication.
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Neoplasias Óseas , Neoplasias de la Mama , Fracturas Óseas , Humanos , Neoplasias Óseas/complicaciones , Neoplasias Óseas/terapia , Neoplasias de la Mama/complicaciones , Neoplasias de la Mama/terapia , Dolor , Calidad de Vida , FemeninoRESUMEN
In applications where high sensitivity is required, the internal gain mechanism of avalanche photodiodes can provide a performance advantage relative to p-i-n photodiodes. However, this internal gain mechanism leads to an excess noise that scales with gain. This excess noise term can be minimized by using materials systems in which impact ionization is initiated primarily by one carrier type. Recently, two Sb-based materials systems, AlInAsSb and AlGaAsSb, have exhibited exceptionally low excess noise, particularly for III-V compound materials. There are four important considerations that can impact the excess noise measurements in such low-noise materials. These considerations deal with the excess noise factor calculation method, measurement RF frequency, measurement wavelength, and the gain calculation method. In this paper, each of these factors is discussed, and their implications on excess noise are considered.
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The thermal properties of modified uni-traveling carrier (MUTC) photodiode flip-chip bonded to AlN and diamond are simulated. The thermal impedance of InGaAs is the primary source of internal heating. An n-down epitaxial structure is designed to improve thermal dissipation. Compared to the conventional p-down configuration, the n-down MUTCs bonded to diamond, or AlN submounts achieved 145% and 110% improvement in dissipated power density at thermal failure, respectively. The improved thermal characteristics presage higher RF output power before thermal failure.
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The group 7 complexes [M(κ3-2,6-(R2PO)2C5H3N)(CO)2L][BArF4] [M = Mn, R = iPr, L = THF; M = Re, R = tBu, L = vacant site] undergo in crystallo solid-gas reactivity with CO to form the products of THF substitution or CO addition respectively. There is a large, local, adaptive change of [BArF4] anions for M = Mn, whereas for M = Re the changes are smaller and also remote to the site of reactivity.
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The sigma amine-borane complexes [Rh(L1)(η2 :η2 -H3 Bâ NRH2 )][OTf] (L1=2,6-bis-[1-(2,6-diisopropylphenylimino)ethyl]pyridine, R=Me, Et, n Pr) are described, alongside [Rh(L1)(NMeH2 )][OTf]. Using R=Me as a pre-catalyst (1â mol %) the dehydropolymerization of H3 B â NMeH2 gives [H2 BNMeH]n selectively. Added NMeH2 , or the direct use of [Rh(L1)(NMeH2 )][OTf], is required for initiation of catalysis, which is suggested to operate through the formation of a neutral hydride complex, Rh(L1)H. The formation of small (1-5â nm) nanoparticles is observed at the end of catalysis, but studies are ambiguous as to whether the catalysis is solely nanoparticle promoted or if there is a molecular homogeneous component. [Rh(L1)(NMeH2 )][OTf] is shown to operate at 0.025â mol % loadings on a 2â g scale of H3 B â NMeH2 to give polyaminoborane [H2 BNMeH]n [Mn =30,900â g/mol, Ð=1.8] that can be purified to a low residual [Rh] (6â µg/g). Addition of Na[N(SiMe3 )2 ] to [H2 BNMeH]n results in selective depolymerization to form the eee-isomer of N,N,N-trimethylcyclotriborazane [H2 BNMeH]3 : the chemical repurposing of a main-group polymer.
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Al0.85Ga0.15As0.56Sb0.44 has recently attracted significant research interest as a material for 1550 nm low-noise short-wave infrared (SWIR) avalanche photodiodes (APDs) due to the very wide ratio between its electron and hole ionization coefficients. This work reports new experimental excess noise data for thick Al0.85Ga0.15As0.56Sb0.44 PIN and NIP structures, measuring low noise at significantly higher multiplication values than previously reported (F = 2.2 at M = 38). These results disagree with the classical McIntyre excess noise theory, which overestimates the expected noise based on the ionization coefficients reported for this alloy. Even the addition of 'dead space' effects cannot account for these discrepancies. The only way to explain the low excess noise observed is to conclude that the spatial probability distributions for impact ionization of electrons and holes in this material follows a Weibull-Fréchet distribution function even at relatively low electric-fields. Knowledge of the ionization coefficients alone is no longer sufficient to predict the excess noise properties of this material system and consequently the electric-field dependent electron and hole ionization probability distributions are extracted for this alloy.
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OBJECTIVE: To investigate the effect of printing material and air abrasion of bracket pads on the shear bond strength of 3D-printed plastic orthodontic brackets when bonded to the enamel of extracted human teeth. MATERIALS AND METHODS: Premolar brackets were 3D-printed using the design of a commercially available plastic bracket in two biocompatible resins: Dental LT Resin and Dental SG Resin (n = 40/material). 3D-printed brackets and commercially manufactured plastic brackets were divided into two groups (n = 20/group), one of which was air abraded. All brackets were bonded to extracted human premolars, and shear bond strength tests were performed. The failure types of each sample were classified using a 5-category modified adhesive remnant index (ARI) scoring system. RESULTS: Bracket material and bracket pad surface treatment presented statistically significant effects for shear bond strengths, and a significant interaction effect between bracket material and bracket pad surface treatment was observed. The non-air abraded (NAA) SG group (8.87 ± 0.64 MPa) had a statistically significantly lower shear bond strength than the air abraded (AA) SG group (12.09 ± 1.23 MPa). In the manufactured brackets and LT Resin groups, the NAA and AA groups were not statistically significantly different within each resin. A significant effect of bracket material and bracket pad surface treatment on ARI score was observed, but no significant interaction effect between bracket material and pad treatment was found. CONCLUSION: 3D-printed orthodontic brackets presented clinically sufficient shear bond strengths both with and without AA prior to bonding. The effect of bracket pad AA on shear bond strength depends on the bracket material.