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1.
Nat Commun ; 13(1): 2984, 2022 05 27.
Artigo em Inglês | MEDLINE | ID: mdl-35624096

RESUMO

DNA-based data storage platforms traditionally encode information only in the nucleotide sequence of the molecule. Here we report on a two-dimensional molecular data storage system that records information in both the sequence and the backbone structure of DNA and performs nontrivial joint data encoding, decoding and processing. Our 2DDNA method efficiently stores images in synthetic DNA and embeds pertinent metadata as nicks in the DNA backbone. To avoid costly worst-case redundancy for correcting sequencing/rewriting errors and to mitigate issues associated with mismatched decoding parameters, we develop machine learning techniques for automatic discoloration detection and image inpainting. The 2DDNA platform is experimentally tested by reconstructing a library of images with undetectable or small visual degradation after readout processing, and by erasing and rewriting copyright metadata encoded in nicks. Our results demonstrate that DNA can serve both as a write-once and rewritable memory for heterogenous data and that data can be erased in a permanent, privacy-preserving manner. Moreover, the storage system can be made robust to degrading channel qualities while avoiding global error-correction redundancy.


Assuntos
DNA , Aprendizado de Máquina , DNA/genética , Biblioteca Gênica , Armazenamento e Recuperação da Informação , Metadados
2.
J Dairy Sci ; 105(1): 72-82, 2022 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-34756437

RESUMO

Shelf-stable cultured milk beverages that have high protein levels can be difficult to successfully manufacture. With increasing protein level, rapid phase separation and gel formation occur in cultured beverages, which may not be prevented even with the inclusion of stabilizers such as high methoxy (HM) pectin. To limit protein aggregation in cultured milk beverages we investigated micellar casein as an interesting alternative to milk, due to the absence of whey proteins, which can contribute to increased gel strength in cultured products. In this study, micellar casein dispersed in ultrafiltered milk permeate was fermented to pH 4.1, blended with HM pectin, homogenized, thermally processed, and bottled for storage at ambient temperature for 6 mo. Utilizing response surface methodology with a central composite rotatable design, the protein and pectin contents were varied between 5 and 9% and 0.0 and 1.0%, respectively. The elastic modulus, loss tangent, and yield stress of these beverages were measured during storage to observe the extent of bond restructuring, whereas particle size and visual phase separation were measured to determine stability. Response variables were measured initially after thermally processing the beverages, and after 1 and 6 mo of storage at ambient temperature. All samples quickly formed gels after homogenizing, regardless of the pectin level. The stiffness (elastic modulus) of all samples increased throughout storage and was determined mainly by the protein content; however, the growth of elastic bonds over time was slowed with high levels of pectin. At 6 mo of storage, yield stress values were significantly lower for beverages with <7.5% protein when they were stabilized with ≥0.85% pectin. Prediction models for visual phase separation in beverages stored for 6 mo were significantly affected by the protein content, with increasing instability at lower protein levels. Models were used to identify optimal protein (<7.5%) and pectin (≥0.85%) concentrations to minimize the stiffness of gels during ambient storage. Samples in this optimized region were predicted to have low yield stress values and were easily fluidized by gentle shaking of the bottle at 6 mo.


Assuntos
Caseínas , Produtos Fermentados do Leite , Animais , Bebidas , Géis , Concentração de Íons de Hidrogênio , Leite , Proteínas do Leite , Pectinas , Reologia , Temperatura
3.
J Prev Med Hyg ; 61(2): E194-E199, 2020 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-32803005

RESUMO

INTRODUCTION: Urinary tract infection, as an important health element is associated with the risk of many problems in pregnancy and support consulting is effective factor in reducing the problem. Aim of this study is to evaluate the impacts of integrated intervention on life style (clothing way, food habits, urinary habits, sexual behavior habits) Related to Urinary Tract Infection Among Pregnant women. METHOD: This interventional used pretest- posttest design with the control group study was performed on 130 healthy pregnant women. The samples were divided randomly into two groups of 65 people. The first group received two sessions of 45 to 60 minutes Psychoeducational counseling, four telephone follow-up support and training pamphlets and the control group received routine education. The relevant questionnaires were completed by both groups before the intervention and a month later. The data were analyzed with Spss V.22 software. RESULTS: Comparing within the groups it was shown that the variables were increased in the experimental group after consulting compared to the conditions before consulting (P < 0.001), however, no increasing was found in the average variables before consulting and after it. Moreover, comparing the variables in two experimental and control groups significant statistical difference was found in different studied areas after consulting (P < 0.0001). CONCLUSIONS: Psychological counseling and phone follow-up are effective in improving the knowledge, attitude, and performance of pregnant women in preventing the urinary infection Therefor it is recommended these trends to be considered as training programs in order to increase capacity and primary prevention of pregnant women.


Assuntos
Hábitos , Promoção da Saúde/organização & administração , Estilo de Vida , Comportamento Sexual , Infecções Urinárias , Adulto , Aconselhamento , Feminino , Humanos , Gestantes , Inquéritos e Questionários , Adulto Jovem
4.
Sci Rep ; 10(1): 7026, 2020 Apr 22.
Artigo em Inglês | MEDLINE | ID: mdl-32321929

RESUMO

An amendment to this paper has been published and can be accessed via a link at the top of the paper.

5.
Science ; 367(6475): 285-288, 2020 01 17.
Artigo em Inglês | MEDLINE | ID: mdl-31949077

RESUMO

Strange metal behavior is ubiquitous in correlated materials, ranging from cuprate superconductors to bilayer graphene, and may arise from physics beyond the quantum fluctuations of a Landau order parameter. In quantum-critical heavy-fermion antiferromagnets, such physics may be realized as critical Kondo entanglement of spin and charge and probed with optical conductivity. We present terahertz time-domain transmission spectroscopy on molecular beam epitaxy-grown thin films of YbRh2Si2, a model strange-metal compound. We observed frequency over temperature scaling of the optical conductivity as a hallmark of beyond-Landau quantum criticality. Our discovery suggests that critical charge fluctuations play a central role in the strange metal behavior, elucidating one of the long-standing mysteries of correlated quantum matter.

6.
Front Psychol ; 11: 588948, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-33716840

RESUMO

"Dance" has been associated with many psychophysiological and medical health effects. However, varying definitions of what constitute "dance" have led to a rather heterogenous body of evidence about such potential effects, leaving the picture piecemeal at best. It remains unclear what exact parameters may be driving positive effects. We believe that this heterogeneity of evidence is partly due to a lack of a clear definition of dance for such empirical purposes. A differentiation is needed between (a) the effects on the individual when the activity of "dancing" is enjoyed as a dancer within different dance domains (e.g., professional/"high-art" type of dance, erotic dance, religious dance, club dancing, Dance Movement Therapy (DMT), and what is commonly known as hobby, recreational or social dance), and (b) the effects on the individual within these different domains, as a dancer of the different dance styles (solo dance, partnering dance, group dance; and all the different styles within these). Another separate category of dance engagement is, not as a dancer, but as a spectator of all of the above. "Watching dance" as part of an audience has its own set of psychophysiological and neurocognitive effects on the individual, and depends on the context where dance is witnessed. With the help of dance professionals, we first outline some different dance domains and dance styles, and outline aspects that differentiate them, and that may, therefore, cause differential empirical findings when compared regardless (e.g., amount of interpersonal contact, physical exertion, context, cognitive demand, type of movements, complexity of technique and ratio of choreography/improvisation). Then, we outline commonalities between all dance styles. We identify six basic components that are part of any dance practice, as part of a continuum, and review and discuss available research for each of them concerning the possible health and wellbeing effects of each of these components, and how they may relate to the psychophysiological and health effects that are reported for "dancing": (1) rhythm and music, (2) sociality, (3) technique and fitness, (4) connection and connectedness (self-intimation), (5) flow and mindfulness, (6) aesthetic emotions and imagination. Future research efforts might take into account the important differences between types of dance activities, as well as the six components, for a more targeted assessment of how "dancing" affects the human body.

7.
Annu Int Conf IEEE Eng Med Biol Soc ; 2019: 4737-4740, 2019 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-31946920

RESUMO

Cardiovascular diseases (CVD) are the leading cause of death in the developed world and aortic aneurysm is a key contributor. Aortic aneurysms typically occur in the thoracic aorta and can extend into the descending aorta. The Frozen Elephant Trunk stent (FET) is one of the leading treatments for the aneurysms extending into the descending aorta. This study focuses on the in-vitro experimentation of a stented descending aorta, investigating the haemodynamics in a compliant phantom. A silicone phantom of the descending aorta was manufactured using a lost core casting method. A PVC stent was manufactured using the same mould core. Particle Image Velocimetry (PIV) was used for pulsatile studies, focusing specifically on the passive fixation at the distal end of the FET. The results showed an apparent expansion in the diastolic period that was identified to be a collapse in the lateral plane. Flow recirculation regions were identified during the collapse. The collapse was attributed to low upstream and high downstream pressures causing a vacuum effect. The findings may imply a potential risk introduced by the FET stent that requires further investigation.


Assuntos
Aorta Torácica/fisiologia , Hemodinâmica , Stents , Aneurisma da Aorta Torácica/terapia , Humanos , Imagens de Fantasmas , Reologia
8.
Sci Rep ; 7(1): 5011, 2017 07 10.
Artigo em Inglês | MEDLINE | ID: mdl-28694453

RESUMO

DNA-based data storage is an emerging nonvolatile memory technology of potentially unprecedented density, durability, and replication efficiency. The basic system implementation steps include synthesizing DNA strings that contain user information and subsequently retrieving them via high-throughput sequencing technologies. Existing architectures enable reading and writing but do not offer random-access and error-free data recovery from low-cost, portable devices, which is crucial for making the storage technology competitive with classical recorders. Here we show for the first time that a portable, random-access platform may be implemented in practice using nanopore sequencers. The novelty of our approach is to design an integrated processing pipeline that encodes data to avoid costly synthesis and sequencing errors, enables random access through addressing, and leverages efficient portable sequencing via new iterative alignment and deletion error-correcting codes. Our work represents the only known random access DNA-based data storage system that uses error-prone nanopore sequencers, while still producing error-free readouts with the highest reported information rate/density. As such, it represents a crucial step towards practical employment of DNA molecules as storage media.


Assuntos
DNA/genética , Sequenciamento de Nucleotídeos em Larga Escala/instrumentação , Análise de Sequência de DNA/instrumentação , Algoritmos , Bases de Dados de Ácidos Nucleicos , Armazenamento e Recuperação da Informação , Nanoporos
9.
Burns ; 42(3): 578-82, 2016 May.
Artigo em Inglês | MEDLINE | ID: mdl-26970838

RESUMO

BACKGROUND AND AIM: Two types of dressing, occlusive and exposure dressing, are commonly used in burn units. A dressing is said to be occlusive if a moist wound surface is maintained when the dressing is in place. This study was designed to compare the effectiveness of occlusive and exposure dressing in controlling burn infections. PATIENTS AND METHODS: Two hundred patients with second-degree burns admitted to Mottahari Hospital, Tehran, Iran, over a period of 12 months from May 2012 to May 2013 were studied. They were divided into two groups of 100 each, to receive either occlusive or exposure dressing. During the first week of treatment, wound specimens were obtained by sterile swab and cultured in selective media. Demographics (age and gender), burn areas, cause of burn, length of hospital stay (LOS), type of infections and time to total healing were compared between the two groups. RESULTS: Occlusive dressing was more susceptible to microbial contamination and infections than exposure dressing. The mean duration of treatment based on epithelialization and healing in occlusive dressing was longer than for exposure dressing. The most common isolate was Pseudomonas spp., followed by Enterobacter, Escherichia coli, Staphylococcus aureus, Acinetobacter, and Klebsiella spp. CONCLUSIONS: Exposure dressing was more suitable than occlusive dressing for treating partial-thickness at our center. Pseudomonas aeruginosa was the most common organism encountered in burn infection.


Assuntos
Queimaduras/terapia , Curativos Oclusivos , Cicatrização , Infecções por Acinetobacter/epidemiologia , Bandagens , Queimaduras/microbiologia , Infecções por Enterobacteriaceae/epidemiologia , Infecções por Escherichia coli/epidemiologia , Feminino , Humanos , Irã (Geográfico)/epidemiologia , Masculino , Infecções por Pseudomonas/epidemiologia , Pseudomonas aeruginosa , Reepitelização , Infecções Estafilocócicas/epidemiologia , Fatores de Tempo , Infecção dos Ferimentos/epidemiologia , Infecção dos Ferimentos/microbiologia
10.
Sci Rep ; 5: 14138, 2015 Sep 18.
Artigo em Inglês | MEDLINE | ID: mdl-26382652

RESUMO

We describe the first DNA-based storage architecture that enables random access to data blocks and rewriting of information stored at arbitrary locations within the blocks. The newly developed architecture overcomes drawbacks of existing read-only methods that require decoding the whole file in order to read one data fragment. Our system is based on new constrained coding techniques and accompanying DNA editing methods that ensure data reliability, specificity and sensitivity of access, and at the same time provide exceptionally high data storage capacity. As a proof of concept, we encoded parts of the Wikipedia pages of six universities in the USA, and selected and edited parts of the text written in DNA corresponding to three of these schools. The results suggest that DNA is a versatile media suitable for both ultrahigh density archival and rewritable storage applications.


Assuntos
DNA , Ciência da Informação , Armazenamento e Recuperação da Informação , Modelos Teóricos , Tecnologia , Algoritmos , DNA/química , DNA/genética
11.
PLoS One ; 9(9): e106576, 2014.
Artigo em Inglês | MEDLINE | ID: mdl-25184295

RESUMO

It has been known for decades that neurons throughout the brain possess solitary, immotile, microtubule based appendages called primary cilia. Only recently have studies tried to address the functions of these cilia and our current understanding remains poor. To determine if neuronal cilia have a role in behavior we specifically disrupted ciliogenesis in the cortex and hippocampus of mice through conditional deletion of the Intraflagellar Transport 88 (Ift88) gene. The effects on learning and memory were analyzed using both Morris Water Maze and fear conditioning paradigms. In comparison to wild type controls, cilia mutants displayed deficits in aversive learning and memory and novel object recognition. Furthermore, hippocampal neurons from mutants displayed an altered paired-pulse response, suggesting that loss of IFT88 can alter synaptic properties. A variety of other behavioral tests showed no significant differences between conditional cilia mutants and controls. This type of conditional allele approach could be used to distinguish which behavioral features of ciliopathies arise due to defects in neural development and which result from altered cell physiology. Ultimately, this could lead to an improved understanding of the basis for the cognitive deficits associated with human cilia disorders such as Bardet-Biedl syndrome, and possibly more common ailments including depression and schizophrenia.


Assuntos
Cílios/metabolismo , Medo , Aprendizagem em Labirinto , Neurogênese/genética , Animais , Síndrome de Bardet-Biedl/genética , Síndrome de Bardet-Biedl/patologia , Córtex Cerebral/metabolismo , Córtex Cerebral/patologia , Cílios/genética , Depressão/genética , Depressão/patologia , Hipocampo/crescimento & desenvolvimento , Hipocampo/metabolismo , Hipocampo/patologia , Humanos , Camundongos , Camundongos Knockout , Neurônios/metabolismo , Neurônios/patologia , Esquizofrenia/genética , Esquizofrenia/patologia , Proteínas Supressoras de Tumor/genética
12.
Adv Mater ; 26(9): 1462-7, 2014 Mar 05.
Artigo em Inglês | MEDLINE | ID: mdl-24338762

RESUMO

Well-controlled sub-unit-cell layer-bylayer epitaxial growth of spinel alumina is achieved at room temperature on a TiO2 -terminated SrTiO3 single-crystalline substrate. By tailoring the interface redox reaction, 2D electron gases with mobilities exceeding 3000 cm 2 V(-1) s(-1) are achieved at this novel oxide interface.

14.
Proc Natl Acad Sci U S A ; 110(19): 7796-801, 2013 May 07.
Artigo em Inglês | MEDLINE | ID: mdl-23599282

RESUMO

Although primary cilia are well established as important sensory and signaling structures, their function in most tissues remains unknown. Obesity is a feature associated with some syndromes of cilia dysfunction, such as Bardet-Biedl syndrome (BBS) and Alström syndrome, as well as in several cilia mutant mouse models. Recent data indicate that obesity in BBS mutant mice is due to defects in leptin receptor trafficking and leptin resistance. Furthermore, induction of cilia loss in leptin-responsive proopiomelanocortin neurons results in obesity, implicating cilia on hypothalamic neurons in regulating feeding behavior. Here, we directly test the importance of the cilium as a mediator of the leptin response. In contrast to the current dogma, a longitudinal study of conditional Ift88 cilia mutant mice under different states of adiposity indicates that leptin resistance is present only when mutants are obese. Our studies show that caloric restriction leads to an altered anticipatory feeding behavior that temporarily abrogates the anorectic actions of leptin despite normalized circulating leptin levels. Interestingly, preobese Bbs4 mutant mice responded to the anorectic effects of leptin and did not display other phenotypes associated with defective leptin signaling. Furthermore, thermoregulation and activity measurements in cilia mutant mice are inconsistent with phenotypes previously observed in leptin deficient ob/ob mice. Collectively, these data indicate that cilia are not directly involved in leptin responses and that a defect in the leptin signaling axis is not the initiating event leading to hyperphagia and obesity associated with cilia dysfunction.


Assuntos
Cílios/patologia , Leptina/metabolismo , Obesidade/metabolismo , Animais , Síndrome de Bardet-Biedl/genética , Síndrome de Bardet-Biedl/patologia , Composição Corporal , Modelos Animais de Doenças , Comportamento Alimentar , Camundongos , Camundongos Obesos , Camundongos Transgênicos , Atividade Motora , Mutação , Neurônios/metabolismo , Obesidade/genética , Obesidade/patologia , Fenótipo , Transdução de Sinais , Temperatura
15.
Biomicrofluidics ; 7(2): 21501, 2013 Apr 05.
Artigo em Inglês | MEDLINE | ID: mdl-24404005

RESUMO

Focusing and sorting cells and particles utilizing microfluidic phenomena have been flourishing areas of development in recent years. These processes are largely beneficial in biomedical applications and fundamental studies of cell biology as they provide cost-effective and point-of-care miniaturized diagnostic devices and rare cell enrichment techniques. Due to inherent problems of isolation methods based on the biomarkers and antigens, separation approaches exploiting physical characteristics of cells of interest, such as size, deformability, and electric and magnetic properties, have gained currency in many medical assays. Here, we present an overview of the cell/particle sorting techniques by harnessing intrinsic hydrodynamic effects in microchannels. Our emphasis is on the underlying fluid dynamical mechanisms causing cross stream migration of objects in shear and vortical flows. We also highlight the advantages and drawbacks of each method in terms of throughput, separation efficiency, and cell viability. Finally, we discuss the future research areas for extending the scope of hydrodynamic mechanisms and exploring new physical directions for microfluidic applications.

16.
East Mediterr Health J ; 18(1): 24-30, 2012 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-22360007

RESUMO

In Chaharborj, a village in north-eastern ofthe Islamic Republic of Iran, a high prevalence of congenital blindness (1.1%) has been reported. The clinical findings have not been fully described. We therefore assessed the clinical aspects of this condition in a case series of 20 congenitally blind patients and 24 of their parents. All patients had been blind since birth. There was anterior segment dysgenesis and retinal non-attachment in all patients. There were no systemic anomalies. Histopathologically, there was iridocorneal adhesion, normal angle structure and retinal dysplasia. No significant difference was found in the frequency of different HLA class I alleles compared with the general population. The anomaly causing congenital blindness in these patients has components of both anterior and posterior segment dysgenesis. It appears to be a distinct entity with an autosomal recessive pattern of inheritance.


Assuntos
Segmento Anterior do Olho/anormalidades , Cegueira/congênito , Saúde da Família , Genes Recessivos , Descolamento Retiniano/congênito , Adolescente , Adulto , Segmento Anterior do Olho/patologia , Cegueira/genética , Cegueira/patologia , Criança , Pré-Escolar , Feminino , Humanos , Lactente , Irã (Geográfico) , Masculino , Segmento Posterior do Olho/anormalidades , Segmento Posterior do Olho/patologia , Descolamento Retiniano/genética , Descolamento Retiniano/patologia
17.
Food Chem ; 132(3): 1143-1149, 2012 Jun 01.
Artigo em Inglês | MEDLINE | ID: mdl-29243593

RESUMO

Curcumin, a polyphenolic compound present in turmeric, is a hydrophobic molecule that has been shown to bind to casein micelles. The present work tested the hypothesis that surface changes in the casein micelles caused by heat-induced interactions with the whey proteins would affect the binding of curcumin. Binding was quantified by direct and tryptophan quenching fluorescence spectroscopy. Curcumin binds to the hydrophobic moieties of the casein proteins, with a 10nm blue shift in its fluorescence emission peak, and causes quenching of the intrinsic fluorescence spectra of the proteins. The fluorescence intensity of curcumin increased after heating of milk at 80°C for 10min; a similar trend in the binding constants was also observed with casein micelles separated from the soluble proteins by centrifugation. There was an increase in the non-specific interactions with heating milk at 80°C for 10min, both in milk as well as in casein micelles separated from the serum proteins. The increased capacity of milk proteins to bind curcumin after heat treatment can be attributed to whey protein denaturation, as whey proteins bind to the surface of casein micelles with heating.

18.
(East. Mediterr. health j).
em Inglês | WHO IRIS | ID: who-118241

RESUMO

In Chaharborj, a village in north-eastern of the Islamic Republic of Iran, a high prevalence of congenital blindness [1.1%] has been reported. The clinical findings have not been fully described. We therefore assessed the clinical aspects of this condition in a case series of 20 congenially blind patients and 24 of their parents. All patients had been blind since birth. There was anterior segment dysgenesis and retinal non-attachment in all patients. There were no systemic anomalies. Histopathologically, there was iridocorneal adhesion, normal angle structure and retinal dysplasia. No significant difference was found in the frequency of different HLA class I alleles compared with the general population. The anomaly causing congenital blindness in these patients has components of both anterior and posterior segment dysgenesis. It appears to be a distinct entity with an autosomal recessive pattern of inheritance


Assuntos
Cegueira , Anormalidades do Olho , Oftalmopatias Hereditárias
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