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1.
Nature ; 582(7813): 501-505, 2020 06.
Artigo em Inglês | MEDLINE | ID: mdl-32541968

RESUMO

Quantum key distribution (QKD)1-3 is a theoretically secure way of sharing secret keys between remote users. It has been demonstrated in a laboratory over a coiled optical fibre up to 404 kilometres long4-7. In the field, point-to-point QKD has been achieved from a satellite to a ground station up to 1,200 kilometres away8-10. However, real-world QKD-based cryptography targets physically separated users on the Earth, for which the maximum distance has been about 100 kilometres11,12. The use of trusted relays can extend these distances from across a typical metropolitan area13-16 to intercity17 and even intercontinental distances18. However, relays pose security risks, which can be avoided by using entanglement-based QKD, which has inherent source-independent security19,20. Long-distance entanglement distribution can be realized using quantum repeaters21, but the related technology is still immature for practical implementations22. The obvious alternative for extending the range of quantum communication without compromising its security is satellite-based QKD, but so far satellite-based entanglement distribution has not been efficient23 enough to support QKD. Here we demonstrate entanglement-based QKD between two ground stations separated by 1,120 kilometres at a finite secret-key rate of 0.12 bits per second, without the need for trusted relays. Entangled photon pairs were distributed via two bidirectional downlinks from the Micius satellite to two ground observatories in Delingha and Nanshan in China. The development of a high-efficiency telescope and follow-up optics crucially improved the link efficiency. The generated keys are secure for realistic devices, because our ground receivers were carefully designed to guarantee fair sampling and immunity to all known side channels24,25. Our method not only increases the secure distance on the ground tenfold but also increases the practical security of QKD to an unprecedented level.

2.
Proc Natl Acad Sci U S A ; 119(48): e2215328119, 2022 11 29.
Artigo em Inglês | MEDLINE | ID: mdl-36409894

RESUMO

Super-enhancers (SEs) are exceptionally large enhancers and are recognized to play prominent roles in cell identity in mammalian species. We surveyed the genomic regions containing large clusters of accessible chromatin regions (ACRs) marked by deoxyribonuclease (DNase) I hypersensitivity in Arabidopsis thaliana. We identified a set of 749 putative SEs, which have a minimum length of 1.5 kilobases and represent the top 2.5% of the largest ACR clusters. We demonstrate that the genomic regions associating with these SEs were more sensitive to DNase I than other nonpromoter ACRs. The SEs were preferentially associated with topologically associating domains. Furthermore, the SEs and their predicted cognate genes were frequently associated with organ development and tissue identity in A. thaliana. Therefore, the A. thaliana SEs and their cognate genes mirror the functional characteristics of those reported in mammalian species. We developed CRISPR/Cas-mediated deletion lines of a 3,578-bp SE associated with the thalianol biosynthetic gene cluster (BGC). Small deletions (131-157 bp) within the SE resulted in distinct phenotypic changes and transcriptional repression of all five thalianol genes. In addition, T-DNA insertions in the SE region resulted in transcriptional alteration of all five thalianol genes. Thus, this SE appears to play a central role in coordinating the operon-like expression pattern of the thalianol BGC.


Assuntos
Arabidopsis , Triterpenos , Animais , Arabidopsis/genética , Sequências Reguladoras de Ácido Nucleico , Cromatina/genética , Mamíferos/genética
3.
Genomics ; 116(1): 110756, 2024 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-38061479

RESUMO

To address the challenges faced by forensic examiners in degraded DNA analysis, we have developed two different panels for various forensic applications, encompassing an AIM-InDel panel for ancestry inference and a Multi-InDel panel for individual identification, respectively. Herein, the efficiencies of these two panels were tested in the Chinese Hui group. By calculating forensic parameters and simulating family relationships, we verified that the Multi-InDel panel could be an effective tool for individual identification, paternity testing, and could assist in kinship identification in the Hui group. For full siblings, the true positive rate of kinship discrimination was 96.553%, when the threshold of log10LR was 1. The cumulative probability of matching as well as cumulative probability of exclusion were 3.8117 × 10-26 and 0.999999722, respectively. Meanwhile, we found that the AIM-InDel panel was effective for bio-geographic ancestry inference, with the vast majority of loci contributing significantly to distinguish East Asian, African, and European populations. By studying the population structure of the Hui ethnic minority, the genetic distance to the Beijing Han population was the closest among the 26 reference populations, which was similar to previous reports. In summary, we have developed two panels which can be effectively applied to the Hui group for individual identification, parentage testing and bio-geographic ancestry inference.


Assuntos
População do Leste Asiático , Etnicidade , Grupos Minoritários , Humanos , China , Etnicidade/genética , Frequência do Gene , Genética Populacional , Mutação INDEL , Fenótipo , População do Leste Asiático/genética
4.
Genomics ; 115(3): 110620, 2023 05.
Artigo em Inglês | MEDLINE | ID: mdl-37037275

RESUMO

To assist in forensic DNA investigation, we developed a new panel capable of simultaneously amplifying 56 ancestry-informative InDels, three Y-InDels and the Amelogenin locus in one PCR reaction. The fragment lengths of the InDel amplicons in this panel were restricted to <200 bp to benefit degraded DNA analysis. In this study, we explored the efficiency of this new panel for forensic applications in the Han Chinese population, and further shed light on the genetic structures of Han populations. We showed that the new panel could be served as an efficient tool for ancestry inference of intercontinental populations. Especially, the Han individuals in different regions could be 100% correctly predicted to be of East Asian origin with this new panel. The Han populations in different regions shared similar ancestry components in their genetic structures. Besides, we also revealed that the new panle could be useful for individual identification in different Han Chinese populations. In conclusion, we have provided the necessary evidence that the self-constructed new panel could play an important role in forensic DNA investigation.


Assuntos
População do Leste Asiático , Genética Populacional , Humanos , DNA , Frequência do Gene
5.
J Mol Evol ; 91(6): 922-934, 2023 12.
Artigo em Inglês | MEDLINE | ID: mdl-38006428

RESUMO

Deletion/insertion polymorphism (DIP) is one of the more promising genetic markers in the field of forensic genetics for personal identification and biogeographic ancestry inference. In this research, we used an in-house developed ancestry-informative marker-DIP system, including 56 autosomal diallelic DIPs, three Y-chromosomal DIPs, and an Amelogenin gene, to analyze the genetic polymorphism and ancestral composition of the Chinese Korean group, as well as to explore its genetic relationships with the 26 reference populations. The results showed that this novel panel exhibited high genetic polymorphism in the studied Korean group and could be effectively applied for forensic individual identification in the Korean group. In addition, the results of multiple population genetic analyses indicated that the ancestral component of the Korean group was dominated by northern East Asia. Moreover, the Korean group was more closely related to the East Asian populations, especially to the Japanese population in Tokyo. This study enriched the genetic data of the Korean ethnic group in China and provided information on the ancestry of the Korean group from the perspective of population genetics.


Assuntos
Etnicidade , Polimorfismo Genético , Humanos , Etnicidade/genética , Genética Populacional , China , República da Coreia , Frequência do Gene , Polimorfismo de Nucleotídeo Único
6.
Phys Rev Lett ; 131(10): 100802, 2023 Sep 08.
Artigo em Inglês | MEDLINE | ID: mdl-37739363

RESUMO

Measurement-device-independent quantum key distribution (MDI QKD) provides immunity against all attacks targeting measurement devices. It is essential to implement MDI QKD in the future global-scale quantum communication network. Toward this goal, we demonstrate a robust MDI QKD fully covering daytime, overcoming the high background noise that prevents BB84 protocol even when using a perfect single-photon source. Based on this, we establish a hybrid quantum communication network that integrates free-space and fiber channels through Hong-Ou-Mandle (HOM) interference. Additionally, we investigate the feasibility of implementing HOM interference with moving satellites. Our results serve as a significant cornerstone for future integrated space-ground quantum communication networks that incorporate measurement-device-independent security.

7.
Opt Express ; 30(7): 11684-11692, 2022 Mar 28.
Artigo em Inglês | MEDLINE | ID: mdl-35473107

RESUMO

Quantum interference plays an essential role in understanding the concepts of quantum physics. Moreover, the interference of photons is indispensable for large-scale quantum information processing. With the development of quantum networks, interference of photons transmitted through long-distance fiber channels has been widely implemented. However, quantum interference of photons using free-space channels is still scarce, mainly due to atmospheric turbulence. Here, we report an experimental demonstration of Hong-Ou-Mandel interference with photons transmitted by free-space channels. Two typical photon sources, i.e., correlated photon pairs generated in spontaneous parametric down conversion (SPDC) process and weak coherent states, are employed. A visibility of 0.744 ± 0.013 is observed by interfering with two photons generated in the SPDC process, exceeding the classical limit of 0.5. Our results demonstrate that the quantum property of photons remains even after transmission through unstable free-space channels, indicating the feasibility and potential application of free-space-based quantum interference in quantum information processing.

8.
Phys Rev Lett ; 128(17): 170501, 2022 Apr 29.
Artigo em Inglês | MEDLINE | ID: mdl-35570417

RESUMO

Long-distance quantum state transfer (QST), which can be achieved with the help of quantum teleportation, is a core element of important quantum protocols. A typical situation for QST based on teleportation is one in which two remote communication partners (Alice and Bob) are far from the entanglement source (Charlie). Because of the atmospheric turbulence, it is challenging to implement the Bell-state measurement after photons propagate in atmospheric channels. In previous long-distance free-space experiments, Alice and Charlie always perform local Bell-state measurement before the entanglement distribution process is completed. Here, by developing a highly stable interferometer to project the photon into a hybrid path-polarization dimension and utilizing the satellite-borne entangled photon source, we demonstrate proof-of-principle QST at the distance of over 1200 km assisted by prior quantum entanglement shared between two distant ground stations with the satellite Micius. The average fidelity of transferred six distinct quantum states is 0.82±0.01, exceeding the classical limit of 2/3 on a single copy of a qubit.

9.
Postgrad Med J ; 97(1152): 644-649, 2021 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-32917776

RESUMO

BACKGROUND: Ischaemic stroke and transient ischaemic attack (TIA) share a common cause. We aim to develop and validate a concise prognostic nomogram for patients with minor stroke and TIA. METHODS: A total of 994 patients with minor stroke and TIA were included. They were split into a derivation (n=746) and validation (n=248) cohort. The modified Rankin Scale (mRS) scores 3 months after onset were used to assess the prognosis as unfavourable outcome (mRS≥2) or favourable outcome (mRS<2). RESULT: The final model included seven independent predictors: gender, age, baseline National Institute of Health Stroke Scale (NIHSS), hypertension, diabetes mellitus, white blood cell and serum uric acid. The Harrell's concordance index (C-index) of the nomogram for predicting the outcome was 0.775 (95% CI 0.735 to 0.814), which was confirmed by the validation cohort (C-index=0.787 (95% CI 0.722 to 0.853)). The calibration curve showed that the nomogram-based predictions were consistent with actual observation in both derivation cohort and validation cohort. CONCLUSION: The proposed nomogram showed favourable predictive accuracy for minor stroke and TIA. This has the potential to contribute to clinical decision-making.


Assuntos
Isquemia Encefálica/diagnóstico , Ataque Isquêmico Transitório/diagnóstico , Nomogramas , Acidente Vascular Cerebral/diagnóstico , Adulto , Idoso , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Valor Preditivo dos Testes , Prognóstico , Reprodutibilidade dos Testes , Ácido Úrico/sangue
10.
Mol Genet Genomics ; 295(4): 957-968, 2020 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-32333170

RESUMO

Studying the genetic structure of each ethnic group is helpful to clarify the genetic background and trace back to the ethnic origin. Tibetan people have lived in the Qinghai-Tibet Plateau (mean elevation over 4500 m) for generations, and have well adapted to the high-altitude environment. Due to the relatively closed geographical environment, Tibetans have preserved their representative physical characteristics and genetic information, thereby become an important research group in human genetics. In this study, genetic characteristics and population structures of two Tibetan groups (Qinghai Tibetans and Tibet Tibetans) were revealed by 35 insertion/deletion polymorphism (DIP) loci, aiming to provide valuable genetic information for population genetic differentiation analyses and forensic identifications. The combined discrimination power, cumulative exclusion probability and combined match probability of the 35 DIP loci in Qinghai Tibetan and Tibet Tibetan groups were 0.9999999999999945, 0.9988, 5.56623 × 10-15; and 0.9999999999999904, 0.9990, 9.69071 × 10-15, respectively, indicating that the panel possessed a strong capability for Tibetan personal identifications. Population differentiations and genetic relationship analyses among the two studied Tibetan groups and other 27 comparison populations were carried out using the Nei's DA genetic distances, population pairwise genetic distances F-statistics (FST), analysis of molecular variance (AMOVA), phylogenetic tree reconstruction, principal component analysis and STRUCTURE methods. Results demonstrated that the most intimate genetic relationships existed in these two Tibetan groups; and genetic similarities between two Tibetan groups and the populations from East Asia were much stronger than that between the Tibetan groups and other geographical populations. Furthermore, forensic ancestral informativeness assessments suggested that several loci could be regarded as ancestry informative markers inferring individual biogeographic origins as well as contributing to forensic anthropology and population genetic researches.


Assuntos
Adaptação Fisiológica/genética , Evolução Molecular , Testes Genéticos , Mutação INDEL/genética , Altitude , China/epidemiologia , Etnicidade/genética , Ásia Oriental , Feminino , Genética Forense , Genética Populacional , Humanos , Masculino , Filogenia , Polimorfismo Genético , Análise de Componente Principal , Tibet/epidemiologia
11.
Opt Express ; 28(1): 369-378, 2020 Jan 06.
Artigo em Inglês | MEDLINE | ID: mdl-32118965

RESUMO

High-fidelity transmission of polarization encoded qubits plays a key role in long distance quantum communication. By establishing the channel between ground and satellite, the communication distance can even exceed thousands of kilometers. Aimed to achieve the efficient uplink quantum communication, here we describe a high-fidelity polarization design of a transmitting antenna with an average polarization extinction ratio of 887:1 by a local test. We also implement a feasible polarization-compensation scheme for satellite motions with a fidelity exceeding 0.995 ± 0.001. Based on these works, we demonstrate the ground-to-satellite entanglment distribution with a violation of Bell inequality by 2.312±0.096, which is well above the classic limit 2.

12.
Opt Express ; 28(24): 36600-36610, 2020 Nov 23.
Artigo em Inglês | MEDLINE | ID: mdl-33379750

RESUMO

Satellite-based quantum communication is a promising approach for realizing global-scale quantum networks. For free-space quantum channel, single-mode fiber coupling is particularly important for improving the signal-to-noise ratio of daylight quantum key distribution (QKD) and compatibility with standard fiber-based QKD. However, achieving a highly efficient and stable single-mode coupling efficiency under strong atmospheric turbulence remains experimentally challenging. Here, we develop a single-mode receiver with an adaptive optics (AO) system based on a modal version of the stochastic parallel gradient descent (M-SPGD) algorithm and test its performance over an 8 km urban terrestrial free-space channel. Under strong atmospheric turbulence, the M-SPGD AO system obtains an improvement of about 3.7 dB in the single-mode fiber coupling efficiency and a significant suppression of fluctuation, which can find its applications in free-space long-range quantum communications.

13.
Phys Rev Lett ; 125(26): 260503, 2020 Dec 31.
Artigo em Inglês | MEDLINE | ID: mdl-33449747

RESUMO

Measurement-device-independent quantum key distribution (MDI-QKD), based on two-photon interference, is immune to all attacks against the detection system and allows a QKD network with untrusted relays. Since the MDI-QKD protocol was proposed, fiber-based implementations aimed at longer distance, higher key rates, and network verification have been rapidly developed. However, owing to the effect of atmospheric turbulence, MDI-QKD over a free-space channel remains experimentally challenging. Herein, by developing a robust adaptive optics system, high-precision time synchronization and frequency locking between independent photon sources located far apart, we realized the first free-space MDI-QKD over a 19.2-km urban atmospheric channel, which well exceeds the effective atmospheric thickness. Our experiment takes the first step toward satellite-based MDI-QKD. Moreover, the technology developed herein opens the way to quantum experiments in free space involving long-distance interference of independent single photons.

14.
Int J Legal Med ; 134(2): 501-503, 2020 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-30675640

RESUMO

To investigate the genetic variation and forensic efficiency of 19 X-STR loci in the Zhuang and Mulao minorities, we calculated allele frequencies, forensic parameters, and haplotype frequencies of 405 Zhuang and 234 Mulao unrelated healthy individuals from Guangxi Zhuang Autonomous Region of China. Furthermore, we analyzed the population genetic differentiations between the two minorities and other reported Chinese populations.


Assuntos
Cromossomos Humanos X , Etnicidade/genética , Variação Genética , Haplótipos , Repetições de Microssatélites , Povo Asiático/genética , China/etnologia , Feminino , Frequência do Gene , Genética Populacional , Humanos , Masculino
15.
Int J Legal Med ; 132(2): 335-342, 2018 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-28405751

RESUMO

The EX27 System is a 6-dye (i.e., FAM, HEX, TAMAR, ROX, VIG, and SIZ-500) kit that combines the 24 autosomal STR loci (i.e., D3S1358, D13S317, D7S820, D16S539, D1S1656, Penta E, TPOX, TH01, D2S1338, CSF1PO, Penta D, D10S1248, D19S433, vWA, D21S11, D18S51, D6S1043, D8S1179, D5S818, D12S391, FGA, D22S1045, D2S441, SE33) with a Y-STR locus (DYS391), an Indel site (YIndel) and Amelogenin, which is designed to amplify DNA from extracts as well as direct amplification from substrates. The new system contains most of the widely used autosomal STR loci around the world and is sensitive to the male component in mixtures and is more accurate in gender determination owing to the DYS391 and YIndel.To demonstrate the suitability for personal identification and parentage testing, the system was validated for sensitivity of detection, species specificity, inhibitor tolerance, DNA mixtures, reproducibility study, and concordance studies based on the SWGDAM developmental validation guidelines. In view of the results, the EX27 System is a robust and reliable amplification kit which can be used for human identification testing.


Assuntos
Cromossomos Humanos Y , Impressões Digitais de DNA/instrumentação , Repetições de Microssatélites , Amelogenina/genética , Animais , Eletroforese , Humanos , Mutação INDEL , Masculino , Reação em Cadeia da Polimerase , Reprodutibilidade dos Testes , Especificidade da Espécie
16.
IEEE J Transl Eng Health Med ; 12: 359-370, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38606391

RESUMO

Attention Deficit Hyperactivity Disorder (ADHD) is a neurodevelopmental disorder commonly seen in childhood that leads to behavioural changes in social development and communication patterns, often continues into undiagnosed adulthood due to a global shortage of psychiatrists, resulting in delayed diagnoses with lasting consequences on individual's well-being and the societal impact. Recently, machine learning methodologies have been incorporated into healthcare systems to facilitate the diagnosis and enhance the potential prediction of treatment outcomes for mental health conditions. In ADHD detection, the previous research focused on utilizing functional magnetic resonance imaging (fMRI) or Electroencephalography (EEG) signals, which require costly equipment and trained personnel for data collection. In recent years, speech and text modalities have garnered increasing attention due to their cost-effectiveness and non-wearable sensing in data collection. In this research, conducted in collaboration with the Cumbria, Northumberland, Tyne and Wear NHS Foundation Trust, we gathered audio data from both ADHD patients and normal controls based on the clinically popular Diagnostic Interview for ADHD in adults (DIVA). Subsequently, we transformed the speech data into text modalities through the utilization of the Google Cloud Speech API. We extracted both acoustic and text features from the data, encompassing traditional acoustic features (e.g., MFCC), specialized feature sets (e.g., eGeMAPS), as well as deep-learned linguistic and semantic features derived from pre-trained deep learning models. These features are employed in conjunction with a support vector machine for ADHD classification, yielding promising outcomes in the utilization of audio and text data for effective adult ADHD screening. Clinical impact: This research introduces a transformative approach in ADHD diagnosis, employing speech and text analysis to facilitate early and more accessible detection, particularly beneficial in areas with limited psychiatric resources. Clinical and Translational Impact Statement: The successful application of machine learning techniques in analyzing audio and text data for ADHD screening represents a significant advancement in mental health diagnostics, paving the way for its integration into clinical settings and potentially improving patient outcomes on a broader scale.


Assuntos
Transtorno do Deficit de Atenção com Hiperatividade , Adulto , Humanos , Transtorno do Deficit de Atenção com Hiperatividade/diagnóstico , Resultado do Tratamento , Imageamento por Ressonância Magnética
17.
Ann Med ; 56(1): 2304653, 2024 12.
Artigo em Inglês | MEDLINE | ID: mdl-38289926

RESUMO

BACKGROUND: Whether minor ischemic stroke (MIS) patients can benefit from intravenous thrombolysis (IVT) remains controversial. The association between the efficacy of IVT and baseline National Institute of Health Stroke Scale (NIHSS) score is unclear in MIS, while the association in moderate and severe stroke is known. This study aimed to explore the effect of IVT in patients with MIS and analyze its efficacy in patients with different baseline NIHSS scores. METHODS: Patients with a NIHSS score ≤5 within 4.5 h of stroke onset were screened in 32 centers. Patients with and without IVT were matched to a ratio of 1:1 with propensity scores. An excellent outcome was defined as a modified Rankin Scale (mRS) score ≤1 at three months after stroke onset. Safety outcomes included mortality and symptomatic intracranial hemorrhage (sICH). Multivariate analysis was used to compute the adjusted odds ratio (OR) for excellent outcomes. The effect of IVT was further analyzed in subgroups according to the baseline NIHSS score. RESULTS: Of the 23,853 screened, 3336 patients with MIS who arrived at the hospital within 4.5 h of onset were included. The 1163 patients treated with IVT were matched with 1163 patients without IVT. IVT in minor strokes generated an adjusted OR of 1.38 (95% CI: 1.09-1.75, p = 0.009) for excellent outcomes. There were no significant differences in mortality (0.17% vs. 0.09%, p = 1.000) and sICH (0.69% vs. 0.86%, p = 0.813) between patients with and without IVT. Subgroup analysis showed that there was no significant effect of IVT in the baseline NIHSS 0-1 or 2-3 subgroups, with adjusted OR of 0.816 (95% CI 0.437-1.53, p = 0.525) and1.22 (95% CI 0.845-1.77, p = 0.287), respectively. In patients with NIHSS score of 4-5, IVT was significantly effective, with an adjusted OR of 1.53 (95% CI 1.02-2.30, p = 0.038). CONCLUSION: IVT can improve MIS outcomes. The risks of sICH and mortality did not increase, especially in patients with NIHSS scores 4 to 5, who could benefit from IVT significantly.


Overall, intravenous thrombolysis can improve the outcomes of patients with minor stroke.Minor stroke patients with a baseline NIHSS score of 4-5 can benefit the most from intravenous thrombolysis.


Assuntos
Isquemia Encefálica , AVC Isquêmico , Acidente Vascular Cerebral , Humanos , Fibrinolíticos/efeitos adversos , Terapia Trombolítica/efeitos adversos , Isquemia Encefálica/tratamento farmacológico , Isquemia Encefálica/etiologia , Resultado do Tratamento , Acidente Vascular Cerebral/etiologia , AVC Isquêmico/tratamento farmacológico
18.
Forensic Sci Int ; 361: 112065, 2024 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-38889603

RESUMO

Insertion/deletion (InDel) polymorphisms can be used as one of the ancestry-informative markers in ancestry analysis. In this study, a self-developed panel consisting of 56 ancestry-informative InDels was used to investigate the genetic structures and genetic relationships between Chinese Inner Mongolia Manchu group and 26 reference populations. The Inner Mongolia Manchu group was closely related in genetic background to East Asian populations, especially the Han Chinese in Beijing. Moreover, populations from northern and southern East Asia displayed obvious variations in ancestral components, suggesting the potential value of this panel in distinguishing the populations from northern and southern East Asia. Subsequently, four machine learning models were performed based on the 56 AIM-InDel loci to evaluate the performance of this panel in ancestry prediction. The random forest model presented better performance in ancestry prediction, with 91.87% and 99.73% accuracy for the five and three continental populations, respectively. The individuals of the Inner Mongolia Manchu group were assigned to the East Asian populations by the random forest model, and they exhibited closer genetic affinities with northern East Asian populations. Furthermore, the random forest model distinguished 87.18% of the Inner Mongolia Manchus from the East Asian populations, suggesting that the random forest model based on the 56 ancestry-informative InDels could be a potential tool for ancestry analysis.


Assuntos
Impressões Digitais de DNA , Etnicidade , Genética Populacional , Mutação INDEL , Aprendizado de Máquina , Humanos , China , Etnicidade/genética , Impressões Digitais de DNA/métodos , Povo Asiático/genética , Frequência do Gene , Polimorfismo Genético
19.
Int J Legal Med ; 127(2): 369-72, 2013 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-23090362

RESUMO

Nine hundred eighteen DNA-confirmed father-son pairs were typed for 16 Y-chromosomal short tandem repeat (Y-STR) markers by AmpFLSTR® Yfiler™ PCR Amplification kit. In a total of 15,606 allele transmissions, 36 mutations were detected. The average mutation rate across all 16 Y-STR markers was 0.0023 (95 % confidence interval, 0.0016-0.0032). One two-step mutation was found at DYS389II, and all other mutations were single steps. The losses and gains were balanced at all other loci, excluding DYS385 and DYS458, where losses were more frequent than gains. Mutation rates among different Y-STR loci were significantly different (Χ (2) = 69.05, P = 0.000). Mutation rates were correlated with the lengths of the alleles. Alleles with higher number of repeats were more likely to mutate. Mutation rates were also correlated with the gene diversity of the locus (r (2) = 0.565, P = 0.023). Loci with higher gene diversity had higher mutation rates. In addition, the mutation rate of the older father was found to be notably higher than that of the younger father.


Assuntos
Cromossomos Humanos Y , Etnicidade/genética , Genética Populacional , Repetições de Microssatélites , Taxa de Mutação , Alelos , China , Impressões Digitais de DNA , Loci Gênicos , Marcadores Genéticos , Variação Genética , Humanos , Masculino , Meiose
20.
Fa Yi Xue Za Zhi ; 29(1): 43-8, 2013 Feb.
Artigo em Zh | MEDLINE | ID: mdl-23646504

RESUMO

Microbeam X-ray fluorescence (micro-XRF) spectrometry has been raised as an analytical technique of microbeam during the recent years. With its advantages of high sensitivity, small sample requirement, high testing accuracy and non-destruction, the technique is widely utilized in forensic science. This review bases on recent researches at home and abroad, describes its applications including identification of gunshot residue, visualization of fingerprints, discrimination of drug source, production process, and other material evidences of analysis in crime scene. Thanks to the advances in technology, intelligent and portable micro-XRF equipment has appeared to be applied. It is believed that it may be more popular and frequent in administration of forensic science in the near future.


Assuntos
Osso e Ossos/química , Dermatoglifia , Afogamento/diagnóstico , Medicina Legal/métodos , Espectrometria por Raios X/métodos , Crime , Esmalte Dentário/química , Humanos , Limite de Detecção , Zinco/análise
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