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1.
Environ Sci Technol ; 58(27): 12249-12259, 2024 Jul 09.
Artículo en Inglés | MEDLINE | ID: mdl-38935480

RESUMEN

NH3 emissions from industrial sources and possibly future energy production constitute a threat to human health because of their toxicity and participation in PM2.5 formation. Ammonia selective catalytic oxidation to N2 (NH3-SCO) is a promising route for NH3 emission control, but the mechanistic origin of achieving high N2 selectivity remains elusive. Here we constructed a highly N2-selective CuO/TiO2 catalyst and proposed a CuOx dimer active site based on the observation of a quadratic dependence of NH3-SCO reaction rate on CuOx loading, ac-STEM, and ab initio thermodynamic analysis. Combining this with the identification of a critical N2H4 intermediate by in situ DRIFTS characterization, a comprehensive N2H4-mediated reaction pathway was proposed by DFT calculations. The high N2 selectivity originated from the preference for NH2 coupling to generate N2H4 over NH2 dehydrogenation on the CuOx dimer active site. This work could pave the way for the rational design of efficient NH3-SCO catalysts.


Asunto(s)
Amoníaco , Oxidación-Reducción , Amoníaco/química , Catálisis , Nitrógeno/química , Cobre/química
2.
Foods ; 13(9)2024 Apr 28.
Artículo en Inglés | MEDLINE | ID: mdl-38731726

RESUMEN

To enhance the resistant starch (RS) content of corn starch, in this work, carboxymethyl chitosan/corn starch/sodium alginate microcapsules (CMCS/CS/SA) with varying concentrations of SA in a citric acid (CA) solution were designed. As the SA concentration increased from 0.5% to 2%, the swelling of the CMCS/CS/SA microcapsule decreased from 15.28 ± 0.21 g/g to 3.76 ± 0.66 g/g at 95 °C. Comparatively, the onset, peak, and conclusion temperatures (To, Tp, and Tc) of CMCS/CS/SA microcapsules were higher than those of unencapsulated CS, indicating that the dense network structure of microcapsules reduced the contact area between starch granules and water, thereby improving thermal stability. With increasing SA concentration, the intact and dense network of CMCS/CS/SA microcapsules remained less damaged after 120 min of digestion, suggesting that the microcapsules with a high SA concentration provided better protection to starch, thereby reducing amylase digestibility. Moreover, as the SA concentration increased from 0.5% to 2%, the RS content of the microcapsules during in vitro digestion rose from 42.37 ± 0.07% to 57.65 ± 0.45%, attributed to the blocking effect of the microcapsule shell on amylase activity. This study offers innovative insights and strategies to develop functional starch with glycemic control properties, holding significant scientific and practical value in preventing diseases associated with abnormal glucose metabolism.

3.
Front Aging Neurosci ; 16: 1390384, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-38800611

RESUMEN

Objectives: This study aimed to explore the current status and trends of acupuncture for neurodegenerative diseases (NDs) in the last decade and provide new insights for researchers in future studies. Methods: The publications concerning acupuncture treatment for NDs published between 2014 and 2023 were extracted from the Web of Science Core Collection. We used CiteSpace and VOSviewer to analyze data on numbers of annual publications, countries, institutions, cited journals, cited authors, cited references, keywords, and citation bursts about acupuncture for NDs. Results: A total of 635 publications were obtained from 2014 to 2023. We identified the most prolific journals, countries, institutions, authors, patterns of authorship, and the main direction of future research in the field of acupuncture for NDs in the last decade. The country, institution, and journal with the most publications are China (389 articles), Beijing University of Chinese Medicine (56 articles), and Evidence Based Complementary and Alternative Medicine (42 articles), respectively. The high-frequency keywords focused on "Alzheimer's disease," "Parkinson's disease," "acupuncture," "dementia," and "electroacupuncture." The top five keywords in terms of centrality were "cerebral ischemia," "acupuncture stimulation," "fMRI," "apoptosis," and "deep brain stimulation." Conclusion: The results from this bibliometric study provide insight into the research trends in acupuncture therapy for NDs, and the current status and trends of the past decade, which may help researchers confirm the current status, hotspots, and frontier trends in this field.

4.
Brain Res ; 1831: 148814, 2024 May 15.
Artículo en Inglés | MEDLINE | ID: mdl-38395250

RESUMEN

BACKGROUND: Influenced by the global aging population, the incidence of Alzheimer's disease (AD) has increased sharply. In addition to increasing ß-amyloid plaque deposition and tau tangle formation, neurogenesis dysfunction has recently been observed in AD. Therefore, promoting regeneration to improve neurogenesis and cognitive dysfunction can play an effective role in AD treatment. Acupuncture and moxibustion have been widely used in the clinical treatment of neurodegenerative diseases because of their outstanding advantages such as early, functional, and benign two-way adjustment. It is urgent to clarify the effectiveness, greenness, and safety of acupuncture and moxibustion in promoting neurogenesis in AD treatment. METHODS: Senescence-accelerated mouse prone 8 (SAMP8) mice at various ages were used as experimental models to simulate the pathology and behaviors of AD mice. Behavioral experiments, immunohistochemistry, Western blot, and immunofluorescence experiments were used for comparison between different groups. RESULTS: Acupuncture and moxibustion could increase the number of PCNA+ DCX+ cells, Nissl bodies, and mature neurons in the hippocampal Dentate gyrus (DG) of SAMP8 mice, restore the hippocampal neurogenesis, delay the AD-related pathological presentation, and improve the learning and memory abilities of SAMP8 mice. CONCLUSION: The pathological process underlying AD and cognitive impairment were changed positively by improving the dysfunction of neurogenesis. This indicates the promising role of acupuncture and moxibustion in the prevention and treatment of AD.


Asunto(s)
Terapia por Acupuntura , Enfermedad de Alzheimer , Moxibustión , Ratones , Animales , Enfermedad de Alzheimer/terapia , Enfermedad de Alzheimer/patología , Hipocampo/patología , Neurogénesis/fisiología , Giro Dentado/patología , Modelos Animales de Enfermedad
5.
Zhen Ci Yan Jiu ; 48(2): 133-8, 2023 Feb 25.
Artículo en Chino | MEDLINE | ID: mdl-36858408

RESUMEN

OBJECTIVE: To observe the effect of electroacupuncture (EA) at "Baihui"(GV20) and "Shenshu" (BL23) on the pathological injury of neurons in SAMP8 mice and the anti-inflammatory effect on neuron repair, providing a new experimental basis for EA prevention and treatment of Alzheimer's disease. METHODS: Twelve 7-month-old SAMP8 mice were randomly divided into model and EA groups, and 6 SAMR1 mice of the same age and genetic background were used as normal group. Mice in the EA group were needled at GV20 and bilateral BL23, and EA (1 mA, 2 Hz) was applied to bilateral BL23 for 15 min, once daily, 10 d as a course for a total of 4 courses, with an interval of 1 d. Mice in the normal and model groups were captured and fixed in the same way as the EA group. The spatial learning and memory ability was detected by Morris water maze test. Neuronal nuclear antigen (NeuN) positive expression and the number of NeuN-positive cells in dentate gyrus (DG) were detected by immunofluorescence staining. The protein expression levels of ionized calcium binding adapter molecule 1(Iba-1), tumor necrosis factor-α(TNF-α), interleukin (IL)-6 and IL-1ß in hippocampus were detected by Western blot. The ultrastructure of nerve cells in DG was observed by transmission electron microscopy. RESULTS: Compared with the normal group, the average escape latency was prolonged(P<0.01), the number of platform crossing was significantly reduced (P<0.01), the average fluorescence intensity of NeuN and the number of NeuN-positive cells in hippocampus DG region decreased (P<0.05), the expression levels of Iba-1, TNF-α, IL-6 and IL-1ß in hippocampus were increased (P<0.05) in the model group.Compared with the model group, the ave-rage escape latency was shortened (P<0.01), the number of platform crossing times was significantly increased (P<0.01), the average fluorescence intensity of NeuN and the number of NeuN-positive cells in hippocampus DG region increased (P<0.05), the expression levels of Iba-1, TNF-α, IL-6 and IL-1ß in hippocampus were decreased (P<0.05) in the EA group. The morphology of nerve cells in the hippocampus DG region was normal, and the organelles in the cytoplasm were clear, complete and regularly distributed in the normal group. However, the morphology of nerve cells in the model group was seriously irregular, which was also irregular in EA group but somewhat relieved compared with model group. CONCLUSION: EA at GV20 and BL23 can improve the learning and memory ability of SAMP8 mice, which may be related to inhibiting the neuroinflammatory response, increasing the number of neurons and improving the ultrastructure of the DG region of the hippocampus to play the role of neuron protection.


Asunto(s)
Electroacupuntura , Animales , Ratones , Interleucina-6 , Factor de Necrosis Tumoral alfa , Hipocampo , Neuronas
7.
Mitochondrial DNA B Resour ; 7(3): 566-568, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-35402707

RESUMEN

Sinocyclocheilus wenshanensis is a cyprinid fish species endemic to Southwestern China. In this study, we first sequenced and characterized the complete mitochondrial genome (mitogenome) of S. wenshanensis by next-generation sequencing method. The entire length of mitogenome is 16,595 base pairs (bp), containing 13 protein-coding genes, two ribosomal RNA genes, 22 transfer RNA genes, and a control region. Its gene arrangement pattern was identical to other previously reported Sinocyclocheilus fishes. The overall base composition is 31.12% A, 16.63% G, 25.45% T, and 26.80% C, with AT content of 56.57%. Phylogenetic analysis using mitogenome of 26 Cyprinidae fishes showed that S. wenshanensis are closely related to S. aluensis and S. oxycephalus. This work would provide molecular information fundamental to future phylogenetic analyses among Sinocyclocheilus species.

8.
Curr Rev Musculoskelet Med ; 14(6): 406-412, 2021 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-34713383

RESUMEN

PURPOSE OF REVIEW: Patellofemoral pain syndrome (PFPS) accounts for 25 to 40% of all knee disorders. Diagnosis of PFPS is primarily based on history and physical examination, but the findings on physical examination are often subtle and do not consistently correlate with symptoms described. Yoon and Fredericson published a review article in 2006 detailing the physical examination maneuvers most frequently used to assist clinicians in the accurate diagnosis and treatment of PFPS, and our aim in this review is to provide an update on this previous article focusing on the literature published over the past 15 years regarding the topic. RECENT FINDINGS: Since publication of Fredericson's original review article, there have been studies building on the literature specifically surrounding Q angle, patellar tilt, crepitus, strength and functional testing, and physical examination maneuver clustering. Additionally, multiple studies have been conducted on the use of musculoskeletal ultrasound (US) as a diagnostic tool for PFPS. Recent literature has further supported Q angle (when measured utilizing a standardized protocol), crepitus, weakness of hip abductors and extensors, and weakness detected in functional testing as predictors of PFPS while finding inconsistent evidence behind lateral patellar tilt as a predictor of PFPS. The reliability of most physical examination tests alone remain low, but clustering physical examination findings may provide better sensitivities and specificities in diagnosing PFPS. Musculoskeletal US is rapidly gaining popularity, and decreased vastus medialis obliquus (VMO) volume, asymmetry in gluteus medius thickness, intra-articular effusions, and quadriceps and patellar tendon thicknesses have shown value in diagnosing those with PFPS. Additionally, US has the advantage of providing dynamic examination as well as evaluation of the patellofemoral joint in newborns and infants as a predictor of future patellofemoral instability. Further studies are needed to establish the gold standard for diagnosing PFPS and what US findings are truly predictive of PFPS.

9.
ACS Synth Biol ; 10(8): 1874-1881, 2021 08 20.
Artículo en Inglés | MEDLINE | ID: mdl-34259519

RESUMEN

Tunicosaponins are natural products extracted from Psammosilene tunicoides, which is an important ingredient of Yunnan Baiyao Powder, an ancient and famous Asian herbal medicine. The representative aglycones of tunicosaponins are the oleanane-type triterpenoids of gypsogenin and quillaic acid, which were found to manipulate a broad range of virus-host fusion via wrapping the heptad repeat-2 (HR2) domain prevalent in viral envelopes. However, the unknown biosynthetic pathway and difficulty in chemical synthesis hinder the therapeutic use of tunicosaponins. Here, two novel cytochrome P450-dependent monooxygenases that take part in the biosynthesis of tunicosaponins, CYP716A262 (CYP091) and CYP72A567 (CYP099), were identified from P. tunicoides. In addition, the whole biosynthesis pathway of the tunicosaponin aglycones was reconstituted in yeast by transforming the platform strain BY-bAS with the CYP716A262 and CYP716A567 genes, the resulting strain could produce 146.84 and 314.01 mg/L of gypsogenin and quillaic acid, respectively. This synthetic biology platform for complicated metabolic pathways elucidation and microbial cell factories construction can provide alternative sources of important natural products, helping conserve natural plant resources.


Asunto(s)
Caryophyllaceae/genética , Sistema Enzimático del Citocromo P-450 , Ácido Oleanólico , Proteínas de Plantas , Plantas Medicinales/genética , Proteínas de Saccharomyces cerevisiae , Saccharomyces cerevisiae , Sistema Enzimático del Citocromo P-450/genética , Sistema Enzimático del Citocromo P-450/metabolismo , Microorganismos Modificados Genéticamente/genética , Microorganismos Modificados Genéticamente/metabolismo , Ácido Oleanólico/biosíntesis , Ácido Oleanólico/genética , Proteínas de Plantas/genética , Proteínas de Plantas/metabolismo , Saccharomyces cerevisiae/genética , Saccharomyces cerevisiae/metabolismo , Proteínas de Saccharomyces cerevisiae/genética , Proteínas de Saccharomyces cerevisiae/metabolismo , Saponinas/biosíntesis , Saponinas/genética
10.
Chin J Nat Med ; 19(5): 385-390, 2021 May.
Artículo en Inglés | MEDLINE | ID: mdl-33941343

RESUMEN

Two new type B polycyclic polyprenylated acylphloroglucinols (PPAPs) (1 and 2) and a known biogenetic precursor hyperbeanol Q (3) were isolated from the root extract of Hypericum beanii, a medicinal plant widespread in southwest China. Their chemical structures were elucidated by 1D/2D NMR and HRESIMS data analysis, and absolute configurations were determined through detailed electric circular dichroism (ECD) analysis including ECD exciton chirality, Mo2(OAc)4-induced ECD, and ECD comparison. Of these compounds, hyperbeone A (1) is a typical [3.3.1]-type B PPAP with an unusual C-1 geranyl side chain, and hyperberin C (2) possesses a rare bicyclo[5.3.1]hendecane core. Taking compound 3 as a starting point, a plausible biosynthetic pathway to the bicyclic type B frameworks of 1 and 2 was proposed.


Asunto(s)
Hypericum , Floroglucinol/química , Dicroismo Circular , Hypericum/química , Espectroscopía de Resonancia Magnética , Estructura Molecular , Floroglucinol/aislamiento & purificación , Fitoquímicos/química , Fitoquímicos/aislamiento & purificación , Raíces de Plantas/química
11.
Metab Eng ; 61: 131-140, 2020 09.
Artículo en Inglés | MEDLINE | ID: mdl-32454222

RESUMEN

UDP-glycosyltransferase (UGT)-mediated glycosylation is a widespread modification of plant natural products (PNPs), which exhibit a wide range of bioactivities, and are of great pharmaceutical, ecological and agricultural significance. However, functional annotation is available for less than 2% of the family 1 UGTs, which currently has 20,000 members that are known to glycosylate several classes of PNPs. This low percentage illustrates the difficulty of experimental study and accurate prediction of their function. Here, a synthetic biology platform for elucidating the UGT-mediated glycosylation process of PNPs was established, including glycosyltransferases dependent on UDP-glucose and UDP-xylose. This platform is based on reconstructing the specific PNPs biosynthetic pathways in dedicated microbial yeast chassis by the simple method of plug-and-play. Five UGT enzymes were identified as responsible for the biosynthesis of the main glycosylation products of triterpenes in Panax notoginseng, including a novel UDP-xylose dependent glycosyltransferase enzyme for notoginsenoside R1 biosynthesis. Additionally, we constructed a yeast cell factory that yields >1 g/L of ginsenoside compound K. This platform for functional gene identification and strain engineering can serve as the basis for creating alternative sources of important natural products and thereby protecting natural plant resources.


Asunto(s)
Panax notoginseng , Biología Sintética , Triterpenos/metabolismo , Glicosilación , Glicosiltransferasas/genética , Glicosiltransferasas/metabolismo , Panax notoginseng/genética , Panax notoginseng/metabolismo , Proteínas de Plantas/genética , Proteínas de Plantas/metabolismo , Azúcares de Uridina Difosfato/genética , Azúcares de Uridina Difosfato/metabolismo
12.
Skeletal Radiol ; 49(4): 645-650, 2020 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-31760459

RESUMEN

Synovial chondromatosis is a rare disease that causes disability and dysfunction of the involved synovial joint. We describe the second case in the literature of intraligamentous synovial chondromatosis involving the anterior cruciate ligament, confirmed by pathology after arthroscopic removal of the chondral bodies. We also describe associated magnetic resonance imaging findings which may be helpful for diagnosis of this very rare entity.


Asunto(s)
Ligamento Cruzado Anterior/diagnóstico por imagen , Condromatosis Sinovial/diagnóstico por imagen , Imagen por Resonancia Magnética/métodos , Tomografía Computarizada por Tomografía de Emisión de Positrones/métodos , Anciano , Ligamento Cruzado Anterior/cirugía , Artroscopía/métodos , Condromatosis Sinovial/cirugía , Humanos , Masculino , Rango del Movimiento Articular , Recurrencia
13.
Zhongguo Zhong Yao Za Zhi ; 44(21): 4596-4604, 2019 Nov.
Artículo en Chino | MEDLINE | ID: mdl-31872653

RESUMEN

Ginsenoside F1 is a rare ginsenoside in medicinal plants such as Panax ginseng,P. notogingseng and P. quinquefolius. It has strong pharmacological activities of anti-tumor,anti-oxidation and anti-aging. In order to directly produce ginsenoside F1 by using inexpensive raw materials such as glucose,we integrated the codon-optimized P.ginseng dammarenediol-Ⅱ synthase(Syn Pg DDS),P.ginseng protopanaxadiol synthase(Syn Pg PPDS),P. ginseng protopanaxatriol synthase(Syn Pg PPTS) genes and Arabidopsis thaliana cytochrome P450 reductase(At CPR1) gene into triterpene chassis strain BY-T3. The transformant BY-PPT can produce protopanaxatriol. Then we integrated the Sacchromyces cerevisiae phosphoglucomutase 1(PGM1),phosphoglucomutase 2(PGM2) and UDP-glucose pyrophosphorylase 1(UGP1) genes into chassis strain BY-PPT. The UDP-glucose supply module increased UDP-glucose production by 8. 65 times and eventually reached to 44. 30 mg·L-1 while confirmed in the transformant BY-PPT-GM. Next,we integrated the UDPglucosyltransferase Pg3-29 gene which can catalyze protopanaxatriol to produce ginsenoside F1 into chassis strain BY-PPT-GM. The transformant BY-F1 produced a small amount of ginsenoside F1 which was measured as 0. 5 mg·L-1. After the fermentation process was optimized,the titer of ginsenoside F1 could be increased by 900 times to 450. 5 mg·L-1. The high-efficiency UDP-glucose supply module in this study can provide reference for the construction of cell factories for production of saponin,and provide an important basis for further obtaining high-yield ginsenoside yeast cells.


Asunto(s)
Ginsenósidos/metabolismo , Panax , Saccharomyces cerevisiae/metabolismo , Glucosa , Uridina Difosfato Glucosa
14.
Zootaxa ; 4476(1): 130-140, 2018 Sep 13.
Artículo en Inglés | MEDLINE | ID: mdl-30313347

RESUMEN

There are over 60 species within the freshwater fish genus Sinocyclocheilus (Cypriniformes: Cyprinidae) distributed throughout the Yunnan-Guizhou Plateau and its surrounding areas in China. In recent years, the increasing number of new species described has raised some controversy about the validity of several species within this genus, notably the putative sympatric species pair S. qiubeiensis and S. jiuchengensis. To test the validity of S. qiubeiensis and S. jiuchengensis, we analyzed the complete sequences of the mitochondrial cytochrome b (CYTB) gene of 20 identified species and one outgroup species. Phylogenetic relationships were reconstructed using CYTB with maximum likelihood (ML) and Bayesian inference (BI) methods. Our phylogenetic results showed that all individuals of S. qiubeiensis and S. jiuchengensis clustered in one clade with strong support. In addition, the genetic distance between the two species was 0.11%, within the range observed at the intraspecific level. The most recent common ancestor of S. qiubeiensis and S. jiuchengensis dated back to 0.13 million years ago, indicating little time for complete speciation to have occurred. These results clearly support the viewpoint that S. jiuchengensis is a synonym of S. qiubeiensis.


Asunto(s)
Cipriniformes/genética , Citocromos b/genética , Animales , Teorema de Bayes , China , Cyprinidae , ADN Mitocondrial , Filogenia , Análisis de Secuencia de ADN , Simpatría
15.
J Biol Eng ; 12: 14, 2018.
Artículo en Inglés | MEDLINE | ID: mdl-30127848

RESUMEN

BACKGROUND: Synthesis of a variety of biological circuits for specific functional purposes has made a tremendous progress in recent years. The ultimate goal of combining molecular biology and engineering is to realize a functional biocomputer. To address this challenge, all previous efforts work toward building up the bio-computer as the ultimate goal. To this aim, there should be a key module, named control unit (CU), to direct a serious of logic or arithmetic operations within the processor. METHODS: This research task develops a bio-CU to work with a bio-ALU, which is realized from the combination of previously developed genetic logic gates to fulfill the kernel function of CPU as those done in the silicon computer. RESULTS: A possible framework of the bio-CPU has demonstrated how to connect a bio-CU with a bio-ALU to conduct a fetch-decode-execute cycle of a macro instruction. It presents not only capability of 4-bit full adder but coordination of related modules in biocomputer. CONCLUSIONS: We have demonstrated computer simulation for applications of the genetic circuits in biocomputer construction. It's expected to inspire follow-up study to synthesize potential configurations of the future biocomputer.

16.
Artículo en Inglés | MEDLINE | ID: mdl-29983719

RESUMEN

Pulse diagnosis is one of the four diagnostic methods of traditional Chinese medicine. However it suffers from the lack of objective and efficient detection method. We propose a noncontact optical method to detect human wrist pulse, aiming at the precise determination of the temporal and spatial distributions of pulse. The method uses the spatial-carrier digital speckle pattern interferometry (DSPI) to measure the micro/nanoscale skin displacement dynamically. Significant improvements in DSPI measurement have been made to allow the DSPI to detect the comprehensive information of the arterial pulsation at locations of Cun, Guan, and Chi. The experimental results prove that the spatiotemporal distributions of pulse can be obtained by the proposed method. The obtained data can be further used to describe most of the pulse parameters such as rate, rhythm, depth, length, width, and contour.

17.
Zhongguo Zhong Yao Za Zhi ; 43(9): 1844-1850, 2018 May.
Artículo en Chino | MEDLINE | ID: mdl-29902895

RESUMEN

Hederagenin is an effective constituent of many medical plants, such as Clematidis Radix, and has a wide range of applications in anti-tumor, anti-inflammatory, antidepressant, hepatoprotective antibacterial, et al. In order to obtain the efficient production of yeast cells for hederagenin,we successfully cloned and screened out a P450 gene MdMA02 from Malus×domestica which can catalyze oleanolic acid C-23 oxidation with our developed plug and play platform. Its amino acid homology is only 32% as compared to characterized CYP72A68v2. By transforming MdMA02 to the oleanolic acid-producing strain BY-OA, a hederagenin-producing strain was constructed and hederagenin's titer could achieve 101 mg·L⁻¹ using high cell density fermentation, which was 337 times higher than in shake flasks culturing. This study provides a basis for further research on promoting the creation of oleanane-type pentacyclic triterpenoids biosynthetic pathway analysis and relative cell factories construction.


Asunto(s)
Ácido Oleanólico/análogos & derivados , Vías Biosintéticas , Recuento de Células , Ácido Oleanólico/metabolismo , Saccharomyces cerevisiae
18.
IET Syst Biol ; 11(6): 182-189, 2017 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-29125127

RESUMEN

In electronic systems, dynamic random access memory (DRAM) is one of the core modules in the modern silicon computer. As for a bio-computer, one would need a mechanism for storage of bio-information named 'data', which, in binary logic, has two levels, logical high and logical low, or in the normalised form, '1' and '0'. This study proposes a possible genetic DRAM based on the modified electronic configuration, which uses the biological reaction to fulfil an equivalent RC circuit constituting a memory cell. The authors implement fundamental functions of the genetic DRAM by incorporating a genetic toggle switch for data hold. The results of simulation verify that the basic function can be used on a bio-storage module for the future bio-computer.


Asunto(s)
Lógica , Redes Neurales de la Computación
19.
Zool Res ; 37(5): 297-300, 2016 Sep 18.
Artículo en Inglés | MEDLINE | ID: mdl-27686789

RESUMEN

In September and October 2015, a new species of the family Nemacheilidae, Triplophysa tianxingensis sp. nov., was discovered from underground water in Qiubei County, Yunnan Province, China. It can be distinguished from all other troglobiotic Triplophysa species occurring in Yunnan by the following combination of characters: eyes small, a little degenerated; barbels longer; ventral profiles greatly convex; pectoral fin short, attaining a third of the distance from the pectoral-fin base to pelvic fin base; body with many brown blotches; caudal peduncle with fin fold; caudal fin shallowly forked, and free posterior chamber of swim bladder cylindrical.


Asunto(s)
Cuevas , Cipriniformes/clasificación , Animales , China , Cipriniformes/anatomía & histología , Ecosistema , Terminología como Asunto
20.
Microsc Res Tech ; 75(9): 1281-91, 2012 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-22514079

RESUMEN

Microscopic vision measurement precision has been largely limited by inaccurately calibrated model parameters, because image plane is near parallel to reference plane in the narrow depth of field. This article proposes a method of precise microscopic vision measurement based on the adaptive positioning of the camera coordinate frame. The microscopic vision measurement movably attaches the origin of the camera coordinate frame along the optical axis. By finding the optimal position, the nonlinearity of the objective function in calibration optimization is decreased and the optimization sensitivity to initial values is reduced. Therefore, we obtain a high calibration precision and eventually ensure a high measurement precision. Mathematical simulations illustrate that the calibration precision of the proposed microscopic vision measurement model is higher than that of the conventional vision measurement model. The experiment shows that with magnification of 3.024×, the presented system achieves a precision of 0.12% based on the proposed microscopic vision measurement model, which is two times higher than the one based on the conventional vision measurement model.

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