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1.
Sensors (Basel) ; 21(20)2021 Oct 19.
Artigo em Inglês | MEDLINE | ID: mdl-34696138

RESUMO

The classic monitoring methods for detecting faults in automotive vehicles based on on-board diagnostics (OBD) are insufficient when diagnosing several mechanical failures. Other sensing techniques present drawbacks such as high invasiveness and limited physical range. The present work presents a fully noninvasive system for fault detection and isolation in internal combustion engines through sound signals processing. An acquisition system was developed, whose data are transmitted to a smartphone in which the signal is processed, and the user has access to the information. A study of the chaotic behavior of the vehicle was carried out, and the feasibility of using fractal dimensions as a tool to diagnose engine misfire and problems in the alternator belt was verified. An artificial neural network was used for fault classification using the fractal dimension data extracted from the sound of the engine. For comparison purposes, a strategy based on wavelet multiresolution analysis was also implemented. The proposed solution allows a diagnosis without having any contact with the vehicle, with low computational cost, without the need for installing sensors, and in real time. The system and method were validated through experimental tests, with a success rate of 99% for the faults under consideration.


Assuntos
Algoritmos , Redes Neurais de Computação , Processamento de Sinais Assistido por Computador , Análise de Ondaletas
2.
Phys Rev Lett ; 125(24): 247203, 2020 Dec 11.
Artigo em Inglês | MEDLINE | ID: mdl-33412048

RESUMO

The plateau at 1/3 of the saturation magnetization M_{s} in the metamagnet CeSb is accompanied by a state of ferromagnetic layers of spins in an up-up-down sequence. We measured M and the specific heat C in the plateau, spin wave analyses of which reveal two distinct branches of excitations. Those with ΔS_{z}=1 as measured by M, coexist with a much larger population of ΔS_{z}=0 excitations measured by C but invisible to M. The large density of ΔS_{z}=0 excitations, their energy gap, and their seeming lack of interaction with ΔS_{z}=1 excitations suggest an analogy with astrophysical dark matter. Additionally, in the middle of the plateau three sharp jumps in M(H) are seen, the size of which, 0.15%M_{s}, is consistent with fractional quantization of magnetization per site in the down-spin layers.

3.
Phys Rev Lett ; 124(8): 081803, 2020 Feb 28.
Artigo em Inglês | MEDLINE | ID: mdl-32167372

RESUMO

We present the result of an experiment to measure the electric dipole moment (EDM) of the neutron at the Paul Scherrer Institute using Ramsey's method of separated oscillating magnetic fields with ultracold neutrons. Our measurement stands in the long history of EDM experiments probing physics violating time-reversal invariance. The salient features of this experiment were the use of a ^{199}Hg comagnetometer and an array of optically pumped cesium vapor magnetometers to cancel and correct for magnetic-field changes. The statistical analysis was performed on blinded datasets by two separate groups, while the estimation of systematic effects profited from an unprecedented knowledge of the magnetic field. The measured value of the neutron EDM is d_{n}=(0.0±1.1_{stat}±0.2_{sys})×10^{-26} e.cm.

4.
J Am Pharm Assoc (2003) ; 60(6): e365-e369, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32737018

RESUMO

OBJECTIVE: To report a rare case of a hepatitis B patient who developed the Stevens-Johnson syndrome (SJS) secondary to tenofovir use. CASE SUMMARY: A 61-year-old woman presented with complaints of jaundice, difficulty in swallowing, and burning sensation all over the body along with erythematous polymorphic rash on the face, upper limbs, and trunk. She was diagnosed with SJS secondary to tenofovir. The causality of adverse drug reaction was assessed using the World Health Organization-Uppsala Monitoring Centre causality scale, and adverse drug reaction was found to be probable. Tenofovir was withdrawn and the patient was conservatively managed. PRACTICE IMPLICATIONS: Through the observation of this event, we could figure out the association between tenofovir and SJS. Prompt withdrawal of the offending agent and the initiation of therapy with systemic corticosteroids and supportive medication were found to be effective.


Assuntos
Hepatite B , Síndrome de Stevens-Johnson , Tenofovir , Feminino , Humanos , Pessoa de Meia-Idade , Síndrome de Stevens-Johnson/diagnóstico , Síndrome de Stevens-Johnson/etiologia , Tenofovir/efeitos adversos
5.
J Gambl Stud ; 36(1): 343-354, 2020 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-31377916

RESUMO

Prediction and wager on the outcome of games/matches are known as sports betting. Positive attitudes toward sports betting may, in the long run, predict sports betting behavior and gambling-related problems. This study, therefore, examined the influence of gender, age, sports betting knowledge and peer-based gambling on attitudes toward sports betting among young adults in Nigeria. The ex-post facto design was adopted in this cross-sectional survey. The participants were 749 students (42.9% females) of a large tertiary institution in southwest Nigeria. A standardized questionnaire comprising demographics and measures of attitudes toward sports betting, sports betting knowledge and perception of peer gambling behavior was utilized in the study. Results revealed that attitudes toward sports betting are positive for older males who are knowledgeable about sports betting and have friends who gamble. Sports betting knowledge and peer-based gambling stood out as significant predictors of attitudes toward sports betting. The social circles of young adults may be the starting points for initiatives to develop healthy attitudes toward sports betting and preventing gambling-related problems.


Assuntos
Atitude , Jogo de Azar/psicologia , Esportes/psicologia , Estudantes/psicologia , Estudos Transversais , Demografia , Feminino , Jogo de Azar/epidemiologia , Humanos , Masculino , Nigéria , Esportes/estatística & dados numéricos , Estudantes/estatística & dados numéricos , Inquéritos e Questionários , Adulto Jovem
6.
Clin Genet ; 89(3): 371-7, 2016 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-26404489

RESUMO

Otopalatodigital spectrum disorders (OPDSD) include OPD syndromes types 1 and type 2 (OPD1, OPD2), Melnick-Needles syndrome (MNS), and frontometaphyseal dysplasia (FMD). These conditions are clinically characterized by variable skeletal dysplasia associated in males, with extra-skeletal features including brain malformations, cleft palate, cardiac anomalies, omphalocele and obstructive uropathy. Mutations in the FLNA gene have been reported in most FMD and OPD2 cases and in all instances of typical OPD1 and MNS. Here, we report a series of 10 fetuses and a neonatally deceased newborn displaying a multiple congenital anomalies syndrome suggestive of OPDSD and in whom we performed FLNA analysis. We found a global mutation rate of 44%. This series allows expanding the clinical and FLNA mutational spectrum in OPDSD. However, we emphasize difficulties to correctly discriminate OPDSD based on clinical criteria in fetuses due to the major overlap between these conditions. Molecular analyses may help pathologists to refine clinical diagnosis according to the type and the location of FLNA mutations. Discriminating the type of OPDSD is of importance in order to improve the genetic counseling to provide to families.


Assuntos
Anormalidades Craniofaciais/genética , Feto , Filaminas/genética , Deformidades Congênitas da Mão/genética , Mutação , Osteocondrodisplasias/genética , Fenótipo , Anormalidades Craniofaciais/diagnóstico , Anormalidades Craniofaciais/metabolismo , Análise Mutacional de DNA , Feminino , Deformidades Congênitas da Mão/diagnóstico , Deformidades Congênitas da Mão/metabolismo , Humanos , Recém-Nascido , Masculino , Osteocondrodisplasias/diagnóstico , Osteocondrodisplasias/metabolismo , Linhagem
7.
Insect Mol Biol ; 25(1): 1-15, 2016 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-26566705

RESUMO

The western corn rootworm, Diabrotica virgifera virgifera, is an insect pest of corn and population suppression with chemical insecticides is an important management tool. Traits conferring organophosphate insecticide resistance have increased in frequency amongst D. v. virgifera populations, resulting in the reduced efficacy in many corn-growing regions of the USA. We used comparative functional genomic and quantitative trait locus (QTL) mapping approaches to investigate the genetic basis of D. v. virgifera resistance to the organophosphate methyl-parathion. RNA from adult methyl-parathion resistant and susceptible adults was hybridized to 8331 microarray probes. The results predicted that 11 transcripts were significantly up-regulated in resistant phenotypes, with the most significant (fold increases ≥ 2.43) being an α-esterase-like transcript. Differential expression was validated only for the α-esterase (ST020027A20C03), with 11- to 13-fold greater expression in methyl-parathion resistant adults (P < 0.05). Progeny with a segregating methyl-parathion resistance trait were obtained from a reciprocal backcross design. QTL analyses of high-throughput single nucleotide polymorphism genotype data predicted involvement of a single genome interval. These data suggest that a specific carboyxesterase may function in field-evolved corn rootworm resistance to organophosphates, even though direct linkage between the QTL and this locus could not be established.


Assuntos
Besouros/genética , Organofosfatos , Locos de Características Quantitativas , Sequência de Aminoácidos , Animais , Mapeamento Cromossômico , Besouros/enzimologia , Esterases/metabolismo , Feminino , Genoma de Inseto , Técnicas de Genotipagem , Endogamia , Resistência a Inseticidas/genética , Larva , Masculino , Dados de Sequência Molecular
12.
Eur Phys J C Part Fields ; 83(11): 1061, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-38021215

RESUMO

We present a novel Active Magnetic Shield (AMS), designed and implemented for the n2EDM experiment at the Paul Scherrer Institute. The experiment will perform a high-sensitivity search for the electric dipole moment of the neutron. Magnetic-field stability and control is of key importance for n2EDM. A large, cubic, 5 m side length, magnetically shielded room (MSR) provides a passive, quasi-static shielding-factor of about 105 for its inner sensitive volume. The AMS consists of a system of eight complex, feedback-controlled compensation coils constructed on an irregular grid spanned on a volume of less than 1000 m3 around the MSR. The AMS is designed to provide a stable and uniform magnetic-field environment around the MSR, while being reasonably compact. The system can compensate static and variable magnetic fields up to ±50µT (homogeneous components) and ±5µT/m (first-order gradients), suppressing them to a few µT in the sub-Hertz frequency range. The presented design concept and implementation of the AMS fulfills the requirements of the n2EDM experiment and can be useful for other applications, where magnetically silent environments are important and spatial constraints inhibit simpler geometrical solutions.

14.
J Neurophysiol ; 107(7): 1962-9, 2012 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-22262828

RESUMO

Contralateral acoustic stimulation (CAS) with white noise and pure tone stimuli was used to assess frequency specificity of efferent olivocochlear control of cochlear mechanics in the gerbil. Changes of the cochlear amplifier can be monitored by distortion product otoacoustic emissions (DPOAEs), which are a byproduct of the nonlinear amplification by the outer hair cells. We used the quadratic DPOAE f2-f1 as ipsilateral probe, as it is known to be sensitive to efferent olivocochlear activity. White noise CAS, used to evoke efferent activity, had maximal effects on the DPOAE level for f2-stimulus frequencies of 5-7 kHz. The dominant effect during CAS was a DPOAE level increase of up to 13.5 dB. The frequency specificity of the olivocochlear system was evaluated by presenting pure tones (0.5-38 kHz) as contralateral stimuli to evoke efferent activity. Maximal DPOAE level changes were triggered by CAS frequencies close to the frequency of the DPOAE elicitor tones (tested f2 range: 2.5-15 kHz). The effective CAS frequency range covered 1.4-2.4 octaves and was centered 0.42 octaves below the DPOAE elicitor tone f2. The frequency-specific effect of CAS with pure tones suggests a dedicated central control of mechanical adjustments for peripheral frequency processing.


Assuntos
Percepção Auditiva/fisiologia , Limiar Auditivo/fisiologia , Cóclea/fisiologia , Lateralidade Funcional/fisiologia , Emissões Otoacústicas Espontâneas/fisiologia , Estimulação Acústica/métodos , Animais , Feminino , Gerbillinae , Masculino , Ruído , Psicoacústica
15.
Injury ; 52(4): 941-945, 2021 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-33250185

RESUMO

AIM: This paper evaluates computer tomographic morphology of partial ligamentous lesions of the sacroiliac joint. We hypothesised that in antero-posterior compression (APC) injuries the anterior superior portion of the sacroiliac joint (SIJ) should open up the most as suggested by the vector forces outlined in the Young and Burgess classification. METHODS: All patients who underwent operative fixation of a ligamentous APC pelvic injury between July 2009 and December 2015 in a single Level-1 trauma centre were included. Patients were case matched (1:1) to controls without pelvic injury. SIJ width was measured by two independent reviewers at the anterior superior and anterior inferior part of the SIJ. Wilcoxon ranged test was applied for analysis. RESULTS: 70 patients (35 cases, 35 controls) were evaluated. Median inferior and superior SI joint widths were 5.27 (IQR 3.68-7.80) and 4.05 (IQR 3.13-5.31) mm in cases versus 2.24 (IQR 1.83-2.50) and 2.44 (IQR 2.14-2.65) mm in controls, respectively. The difference between the inferior and superior SI width in cases was larger than in controls (p-value < 0.01, median of -0.22 mm in the control group versus 1.51 mm in the cases). CONCLUSION: Our data suggests that the inferior part of the SIJ opens up after injury more, relative to its superior portion. The vector of the force involved in rotationally unstable pelvic injuries is unlikely to be antero-posterior if the force causes the SI joint to widen up inferiorly first. This should be considered in SIJ fixation and challenges the APC mechanism in pure ligamentous rotationally unstable pelvic ring injuries.


Assuntos
Fraturas Ósseas , Ossos Pélvicos , Humanos , Ligamentos Articulares/diagnóstico por imagem , Ligamentos Articulares/cirurgia , Ossos Pélvicos/diagnóstico por imagem , Ossos Pélvicos/cirurgia , Articulação Sacroilíaca/diagnóstico por imagem , Tomografia Computadorizada por Raios X , Centros de Traumatologia
16.
J Exp Med ; 128(6): 1223-36, 1968 Dec 01.
Artigo em Inglês | MEDLINE | ID: mdl-4176936

RESUMO

The gammaA2-subgroup of gammaA-globulins, previously delineated by antigenic studies, was found to differ strikingly from other immunoglobulins in the manner in which the polypeptide chains are bound together. The heavy and light chains were not linked to each other by disulfide bonds. Instead the light chains were disulfide linked to one another, and were present in the gammaA2-molecule as disulfide bridged L-L dimers. Antisera specific for gammaA2-proteins indicated the occurrence of two different antigenic types in all normal sera as well as saliva and colostrum. Both of these showed the unique interchain disulfide linkage. Quantitative analyses indicated higher levels of gammaA2-proteins in external secretions.


Assuntos
Mieloma Múltiplo/imunologia , Compostos de Sulfidrila/análise , gama-Globulinas/análise , Animais , Reações Antígeno-Anticorpo , Cromatografia em Gel , Colostro/imunologia , Eletroforese , Géis , Haplorrinos , Humanos , Soros Imunes , Imunodifusão , Imunoeletroforese , Coelhos , Saliva/imunologia , Amido , Sulfetos
17.
Biochem Soc Trans ; 38(Pt 1): 110-5, 2010 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-20074045

RESUMO

In response to DNA damage, TLS (translesion synthesis) allows replicative bypass of various DNA lesions, which stall normal replication. TLS is achieved by low-fidelity polymerases harbouring less stringent active sites. In humans, Y-family polymerases together with Pol zeta (polymerase zeta) are responsible for TLS across different types of damage. Protein-protein interaction contributes significantly to the regulation of TLS. REV1 plays a central role in TLS because it interacts with all other Y-family members and Pol zeta. Ubiquitin-dependent regulatory mechanisms also play important roles in TLS. Ubiquitin-binding domains have been found in TLS polymerases and they might be required for TLS activity. Mono-ubiquitination of PCNA (proliferating-cell nuclear antigen), the central scaffold of TLS polymerases, is thought to promote TLS. In addition, both non-proteolytic and proteolytic polyubiquitination of PCNA and TLS polymerases has been demonstrated. Owing to their low fidelity, the recruitment of TLS polymerases is strictly restricted to stalled replication forks.


Assuntos
Dano ao DNA , Reparo do DNA , Replicação do DNA , DNA Polimerase Dirigida por DNA/metabolismo , Ubiquitina/metabolismo , Animais , Ciclo Celular/fisiologia , DNA Polimerase Dirigida por DNA/genética , Humanos , Isoenzimas/genética , Isoenzimas/metabolismo , Antígeno Nuclear de Célula em Proliferação/genética , Antígeno Nuclear de Célula em Proliferação/metabolismo , Ubiquitinação
18.
Synth Syst Biotechnol ; 5(4): 252-267, 2020 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-32775710

RESUMO

Cell-free systems that mimic essential cell functions, such as gene expression, have dramatically expanded in recent years, both in terms of applications and widespread adoption. Here we provide a review of cell-extract methods, with a specific focus on prokaryotic systems. Firstly, we describe the diversity of Escherichia coli genetic strains available and their corresponding utility. We then trace the history of cell-extract methodology over the past 20 years, showing key improvements that lower the entry level for new researchers. Next, we survey the rise of new prokaryotic cell-free systems, with associated methods, and the opportunities provided. Finally, we use this historical perspective to comment on the role of methodology improvements and highlight where further improvements may be possible.

19.
Science ; 156(3782): 1609-10, 1967 Jun 23.
Artigo em Inglês | MEDLINE | ID: mdl-4164868

RESUMO

The carboxy-terminal amino acids of alpha-and micro-chains from human immunoglobulins and alpha-chains from mouse immunoglobulins have been determined by carboxypeptidase digestion and hydrazinolysis. The data suggest the following carboxy-terminal sequences: human micro: Ala-Gly-Thr-Cys-TyrCOOH; human alpha: Thr-Cys-TyrCOOH; murine alpha: (Ileu, Cys)-TyrCOOH.


Assuntos
Sequência de Aminoácidos , Peptídeos/análise , Tirosina/análise , gama-Globulinas/análise , Animais , Carboxipeptidases , Cromatografia em Gel , Humanos , Hidrazinas , Camundongos , Biologia Molecular , Mieloma Múltiplo , Plasmocitoma , Macroglobulinemia de Waldenstrom
20.
J Econ Entomol ; 102(2): 699-707, 2009 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-19449652

RESUMO

A monitoring program that used a glass-vial bioassay to detect acephate resistance in populations of the tarnished plant bug, Lygus lineolaris (Palisot de Beauvois) (Heteroptera: Miridae), was carried out with weed-collected populations from 20 sites in the delta of Arkansas, Louisiana, and Mississippi. Additional results from field tests using recommended rates of formulated acephate in cotton showed that plant bug populations with resistance ratio (RR50) values > 3.0 for acephate (from the glass-vial bioassay) would be difficult to control in the field. Over a 4-yr-period from 2001 through 2004, only one population tested with the glass-vial bioassay was found with an RR50 value > 3.0 for acephate, but six populations having RR50 values > 3.0 were found in the delta in 2005. In fall 2005, an additional 10 populations from the hill region (the cotton growing areas outside the delta) were tested and four of these populations had RR50 values > 3.0. The number of populations with RR50 values > 3.0 increased to five of 10 and 18 of 20 in the hills and delta, respectively, in fall 2006. Laboratory tests using resistant populations found that resistance to acephate was not sex-linked and the alleles controlling the resistance were semidominant in nature. Because of the large increase in resistant populations and the nature of the resistance found in this study, along with control problems experienced by growers in 2006, entomologists in the mid-South strongly recommended that alternation of insecticide classes in field treatments for plant bug control be used by growers in 2007. This control strategy probably helped control plant bugs in the hills of MS where plant bug pressure was low in 2007, and only one population was found in the fall with an RR50 value > 3.0. Plant bug pressure was very high in many parts of the delta in 2007, and 15 of the 20 populations tested in the fall had RR50 values > 3.0. In one field test in cotton, a population with multiple resistance was tested and not effectively controlled in treatments using recommended rates of carbamate, organophosphate, and pyrethroid insecticides. Alternation of insecticide classes may not work very well when populations are present that are resistant to three of the four main classes of cotton insecticides. New insecticides in different classes are badly needed for control of tarnished plant bugs in cotton in the mid-South.


Assuntos
Heterópteros/efeitos dos fármacos , Resistência a Inseticidas , Inseticidas/farmacologia , Compostos Organotiofosforados/farmacologia , Animais , Ecossistema , Resistência a Inseticidas/genética , Mississippi , Permetrina/farmacologia , Fosforamidas , Rios
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