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1.
Nature ; 585(7823): 39-42, 2020 09.
Artigo em Inglês | MEDLINE | ID: mdl-32879500

RESUMO

Cosmological models in which dark matter consists of cold elementary particles predict that the dark halo population should extend to masses many orders of magnitude below those at which galaxies can form1-3. Here we report a cosmological simulation of the formation of present-day haloes over the full range of observed halo masses (20 orders of magnitude) when dark matter is assumed to be in the form of weakly interacting massive particles of mass approximately 100 gigaelectronvolts. The simulation has a full dynamic range of 30 orders of magnitude in mass and resolves the internal structure of hundreds of Earth-mass haloes in as much detail as it does for hundreds of rich galaxy clusters. We find that halo density profiles are universal over the entire mass range and are well described by simple two-parameter fitting formulae4,5. Halo mass and concentration are tightly related in a way that depends on cosmology and on the nature of the dark matter. For a fixed mass, the concentration is independent of the local environment for haloes less massive than those of typical galaxies. Haloes over the mass range of 10-3 to 1011 solar masses contribute about equally (per logarithmic interval) to the luminosity produced by dark matter annihilation, which we find to be smaller than all previous estimates by factors ranging up to one thousand3.

2.
Opt Lett ; 48(2): 518-521, 2023 Jan 15.
Artigo em Inglês | MEDLINE | ID: mdl-36638499

RESUMO

We study incoherently coupled two-frequency pulse compounds in waveguides with single zero-dispersion and zero-nonlinearity points. In such waveguides, supported by a negative nonlinearity, soliton dynamics can be obtained even in domains of normal dispersion. We demonstrate trapping of weak pulses by solitary-wave wells, forming nonlinear-photonics meta-atoms, and molecule-like bound-states of pulses. We study the impact of the Raman effect on these pulse compounds, finding that, depending on the precise subpulse configuration, they decelerate, accelerate, or are completely unaffected. Our results extend the range of systems in which two-frequency pulse compounds can be expected to exist and demonstrate further unique and unexpected behavior.

3.
Entropy (Basel) ; 25(3)2023 Mar 02.
Artigo em Inglês | MEDLINE | ID: mdl-36981332

RESUMO

This paper considers the main challenges for all components engaged in the driving task suggested by the automation of road vehicles or autonomous cars. Numerous autonomous vehicle developers often invest an important amount of time and effort in fine-tuning and measuring the route tracking to obtain reliable tracking performance over a wide range of autonomous vehicle speed and road curvature diversities. However, a number of automated vehicles were not considered for fault-tolerant trajectory tracking methods. Motivated by this, the current research study of the Differential Lyapunov Stochastic and Decision Defect Tree Learning (DLS-DFTL) method is proposed to handle fault detection and course tracking for autonomous vehicle problems. Initially, Differential Lyapunov Stochastic Optimal Control (SOC) with customizable Z-matrices is to precisely design the path tracking for a particular target vehicle while successfully managing the noise and fault issues that arise from the localization and path planning. With the autonomous vehicle's low ceilings, a recommendation trajectory generation model is created to support such a safety justification. Then, to detect an unexpected deviation caused by a fault, a fault detection technique known as Decision Fault Tree Learning (DFTL) is built. The DLS-DFTL method can be used to find and locate problems in expansive, intricate communication networks. We conducted various tests and showed the applicability of DFTL. By offering some analysis of the experimental outcomes, the suggested method produces significant accuracy. In addition to a thorough study that compares the results to state-of-the-art techniques, simulation was also used to quantify the rate and time of defect detection. The experimental result shows that the proposed DLS-DFTL enhances the fault detection rate (38%), reduces the loss rate (14%), and has a faster fault detection time (24%) than the state of art methods.

4.
Faraday Discuss ; 213(0): 471-485, 2019 02 18.
Artigo em Inglês | MEDLINE | ID: mdl-30357187

RESUMO

We report a detailed study of neuromorphic switching behaviour in inherently complex percolating networks of self-assembled metal nanoparticles. We show that variation of the strength and duration of the electric field applied to this network of synapse-like atomic switches allows us to control the switching dynamics. Switching is observed for voltages above a well-defined threshold, with higher voltages leading to increased switching rates. We demonstrate two behavioral archetypes and show how the switching dynamics change as a function of duration and amplitude of the voltage stimulus. We show that the state of each synapse can influence the activity of the other synapses, leading to complex switching dynamics. We further demonstrate the influence of the morphology of the network on the measured device properties, and the constraints imposed by the overall network conductance. The correlated switching dynamics, device stability over long periods, and the simplicity of the device fabrication provide an attractive pathway to practical implementation of on-chip neuromorphic computing.

6.
Phys Rev Lett ; 120(21): 210402, 2018 May 25.
Artigo em Inglês | MEDLINE | ID: mdl-29883147

RESUMO

Can the most "classical-like" of all quantum states, namely the Schrödinger coherent state of a harmonic oscillator, exhibit nonclassical behavior? We find that for an oscillating object initially in a coherent state, merely by observing at various instants which spatial region the object is in, the Leggett-Garg inequality (LGI) can be violated through a genuine negative result measurement, thereby repudiating the everyday notion of macrorealism. This violation thus reveals an unnoticed nonclassicality of the very state which epitomizes classicality within the quantum description. It is found that for any given mass and oscillator frequency, a significant quantum violation of LGI can be obtained by suitably choosing the initial peak momentum of the coherent state wave packet. It thus opens up potentially the simplest way (without coupling with any ancillary quantum system or using nonlinearity) for testing whether various recently engineered and sought after macroscopic oscillators, such as feedback cooled thermal trapped nanocrystals of ∼10^{6}-10^{9} amu mass, are indeed bona fide nonclassical objects.

7.
Int J Immunogenet ; 45(1): 1-7, 2018 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-29168332

RESUMO

Rheumatoid arthritis (RA) is a complex, multifactorial, systemic autoimmune disease. Reports are suggestive of the role of HLA especially HLA-DRB1 alterations in RA pathogenesis. Existing data involving different geographical populations on the role of alterations in specific locus of HLA-DRB1 in RA susceptibility and severity are equivocal, with no data available from ethnically distinct North-east Indian population, where RA cases are alarmingly increasing. This study aimed to evaluate the association of HLA-DRB1 gene SNPs (rs13192471, rs660895 and rs6457617) with susceptibility and severity of RA in an ethnically distinct North-east Indian population. Whole blood was collected from clinically characterized RA cases (satisfying the American College of Rheumatology 1987 criteria) (n = 123) and community-based age and sex-matched healthy controls (n = 156) with informed consent. The HLA-DRB1 SNP analysis was performed for all the RA and control cases using ARMS-PCR using case and control genomic DNA as template. Statistical analysis was performed by SPSSv13.0 software. The HLA-DRB1 rs660895 showed both wild (AA) and heterozygote (AG) genotype but the heterozygote allele was found to be associated with reduced risk of RA compared to controls [OR = 0.531, p = .024]. The difference in distribution of rs6457617 polymorphism between RA and control cases was comparable [OR = 0.525, p = .079]. Significantly higher distribution of variant rs13192471 genotype was observed in RA cases (69.92%) compared to controls (46.75%) (p < .001) and was associated with increased risk of susceptibility to RA [OR = 2.576, p < .001] compared to controls, as well as progression to severity in RA cases [OR = 2.404, p = .048]. Combinatorially also, the presence of rs13192471 variant genotype was associated with increased risk of RA susceptibility [OR = 8.267, p = .026] and RA severity [OR = 3.647, p = .280]. Alterations in HLA-DRB1 are associated with RA susceptibility. HLA-DRB1 rs13192471 SNP plays a critical role in RA susceptibility and severity in North-east Indian cases and has prognostic significance in RA.


Assuntos
Artrite Reumatoide/genética , Predisposição Genética para Doença , Genótipo , Cadeias HLA-DRB1/genética , Polimorfismo de Nucleotídeo Único , Adolescente , Adulto , Feminino , Humanos , Masculino , Pessoa de Meia-Idade
8.
Parasite Immunol ; 39(9)2017 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-28686299

RESUMO

The study explored the role of differential RANTES concentrations, its receptor CCR5 expression and resulting immunomodulation in the pathogenesis and/or recovery from falciparum malaria. The study population included cases of uncomplicated malaria (UC-M, N=128, enrolled on follow-up basis), severe malaria (SM, N=25), and healthy controls (N=112). Serum RANTES and TNF-α levels were evaluated by ELISA. Monocyte levels and activation profile were studied by flow cytometry. Differential mRNA expression profile was studied by real-time PCR. Blood parasite count was evaluated by registered pathologists. RANTES concentration was significantly downregulated in SM cases compared to UC-M (P=.046) and controls (P<.001). Expression of monocyte marker mCD14, activation markers CCR5 and CD40, and downstream effector cytokine TNF-α was significantly higher in malaria cases compared to controls, in SM cases compared to UC-M. TNF-α expression correlated positively with CD40 and CCR5 expressions. Follow-up-based analysis showed that RANTES concentrations increased on recovery compared to baseline in UC-M cases (P=.106) and inversely correlated with malaria parasite load, mCD14, CCR5 and CD40, and TNF-α expressions. These findings suggest an important association of RANTES concentrations in Plasmodium falciparum malaria disease pathogenesis, as well as recovery, mediated through differential modulation and regulated activation of monocytes and cytokine TNF-α.


Assuntos
Quimiocina CCL5/sangue , Regulação da Expressão Gênica , Malária Falciparum/diagnóstico , Plasmodium falciparum/imunologia , Adulto , Biomarcadores/análise , Quimiocina CCL5/metabolismo , Citocinas/sangue , Ensaio de Imunoadsorção Enzimática , Feminino , Citometria de Fluxo , Humanos , Malária Falciparum/parasitologia , Masculino , Monócitos/imunologia , Adulto Jovem
9.
Mol Cancer ; 15: 2, 2016 Jan 05.
Artigo em Inglês | MEDLINE | ID: mdl-26728511

RESUMO

BACKGROUND: Zinc (Zn) hyper-accumulates in breast tumors and malignant cell lines compared to normal mammary epithelium. The mechanisms responsible for Zn accumulation and the consequence of Zn dysregulation are poorly understood. METHODS: Microarrays were performed to assess differences in the expression of Zn transporters and metallothioneins (MTs) in human breast tumors and breast cancer cell lines. Real-time PCR and immunoblotting were employed to profile Zn transporter expression in representative luminal (T47D), basal (MDA-MB-231), and non-malignant (MCF10A) cell lines. Zn distribution in human tumors was assessed by X-ray fluorescence imaging. Zn distribution and content in cell lines was measured using FluoZin-3 imaging, and quantification and atomic absorption spectroscopy. Functional consequences of ZnT2 over-expression in MDA-MB-231 cells including invasion, proliferation, and cell cycle were measured using Boyden chambers, MTT assays, and flow cytometry, respectively. RESULTS: Gene expression profiling of human breast tumors and breast cancer cell lines identified subtype-specific dysregulation in the Zn transporting network. X-ray fluorescence imaging of breast tumor tissues revealed Zn hyper-accumulation at the margins of Luminal breast tumors while Zn was more evenly distributed within Basal tumors. While both T47D and MDA-MB-231 cells hyper-accumulated Zn relative to MCF10A cells, T47D cells accumulated 2.5-fold more Zn compared to MDA-MB-231 cells. FluoZin-3 imaging indicated that Zn was sequestered into numerous large vesicles in T47D cells, but was retained in the cytoplasm and found in fewer and larger, amorphous sub-cellular compartments in MDA-MB-231 cells. The differences in Zn localization mirrored the relative abundance of the Zn transporter ZnT2; T47D cells over-expressed ZnT2, whereas MDA-MB-231 cells did not express ZnT2 protein due to proteasomal degradation. To determine the functional relevance of the lack of ZnT2 in MDA-MB-231cells, cells were transfected to express ZnT2. ZnT2 over-expression led to Zn vesicularization, shifts in cell cycle, enhanced apoptosis, and reduced proliferation and invasion. CONCLUSIONS: This comprehensive analysis of the Zn transporting network in malignant breast tumors and cell lines illustrates that distinct subtype-specific dysregulation of Zn management may underlie phenotypic characteristics of breast cancers such as grade, invasiveness, metastatic potential, and response to therapy.


Assuntos
Neoplasias da Mama/classificação , Neoplasias da Mama/patologia , Espaço Intracelular/metabolismo , Zinco/metabolismo , Apoptose , Neoplasias da Mama/genética , Proteínas de Transporte de Cátions/metabolismo , Ciclo Celular , Linhagem Celular Tumoral , Feminino , Perfilação da Expressão Gênica , Regulação Neoplásica da Expressão Gênica , Humanos , Invasividade Neoplásica , Proteínas de Neoplasias/genética , Proteínas de Neoplasias/metabolismo , Análise de Sequência com Séries de Oligonucleotídeos , Fenótipo , Complexo de Endopeptidases do Proteassoma/metabolismo , Proteólise , RNA Mensageiro/genética , RNA Mensageiro/metabolismo , Frações Subcelulares/metabolismo
10.
Phys Rev Lett ; 117(14): 143003, 2016 Sep 30.
Artigo em Inglês | MEDLINE | ID: mdl-27740804

RESUMO

We propose an interferometric scheme based on an untrapped nano-object subjected to gravity. The motion of the center of mass (c.m.) of the free object is coupled to its internal spin system magnetically, and a free flight scheme is developed based on coherent spin control. The wave packet of the test object, under a spin-dependent force, may then be delocalized to a macroscopic scale. A gravity induced dynamical phase (accrued solely on the spin state, and measured through a Ramsey scheme) is used to reveal the above spatially delocalized superposition of the spin-nano-object composite system that arises during our scheme. We find a remarkable immunity to the motional noise in the c.m. (initially in a thermal state with moderate cooling), and also a dynamical decoupling nature of the scheme itself. Together they secure a high visibility of the resulting Ramsey fringes. The mass independence of our scheme makes it viable for a nano-object selected from an ensemble with a high mass variability. Given these advantages, a quantum superposition with a 100 nm spatial separation for a massive object of 10^{9} amu is achievable experimentally, providing a route to test postulated modifications of quantum theory such as continuous spontaneous localization.

11.
Br J Nutr ; 116(10): 1799-1806, 2016 Nov 28.
Artigo em Inglês | MEDLINE | ID: mdl-27866479

RESUMO

A regional cross-country profile of fruit and vegetable (F&V) consumption is lacking in the Eastern Mediterranean Region (EMR). This study examines the prevalence of and differences in consumption of F&V ≥5 times/d among adolescents in eleven EMR countries, and describes differences in the proportions of taking F&V ≥5 times/d by sex, age and BMI. The study included 26 328 school adolescents (13-15 years) with complete data on consumption of F&V, age, sex, weight and height taken from the Global School-based Student Health Survey conducted in the EMR between 2005 and 2009. Overall, only 19·4 % of adolescents reported consuming F&V ≥5 times/d. The highest prevalence was reported in Djibouti (40·4 %) and the lowest was reported in Pakistan (10·0 %). Statistically significant differences in prevalence were observed across countries (P<0·05). With the exception of Oman, Libya and Djibouti, significantly more males than females ate F&V ≥5 times/d. The proportion of students consuming F&V ≥5 times/d also varied significantly in all countries based on BMI (P<0·0001), with students within normal BMI having the highest frequency. A negative trend was observed between age and intake of F&V ≥5 times/d in most of the eleven EMR countries except Jordan, Djibouti and Morocco. The prevalence of adequate intake of F&V is low in the eleven EMR countries. There is a need for interventions to increase the prevalence of adolescents consuming F&V ≥5 times/d. Interventions should take into consideration the psychosocial, environmental and socio-environmental factors influencing F&V intake within countries.

12.
Br J Nutr ; 115(6): 1092-9, 2016 Mar 28.
Artigo em Inglês | MEDLINE | ID: mdl-26817392

RESUMO

Regional cross-country profile of fruit and vegetable (F&V) consumption is lacking in the Eastern Mediterranean Region (EMR). This study examines the prevalence and differences of consuming F&V ≥5 times/d among adolescents in eleven EMR countries, and also describes differences in the proportions of taking F&V ≥5 times/d by sex, age and BMI. The study included 26 328 school adolescents (13-15 years) with complete data on consumption of F&V, age, sex, weight and height taken from the Global School-based Student Health Survey conducted in the EMR between 2005 and 2009. Overall, only 19·4 % of adolescents reported consuming F&V ≥5 times/d. The highest prevalence was reported in Djibouti (40·4 %) and the lowest was reported in Pakistan (10·0 %). Statistically significant differences in prevalence were observed across countries (P<0·05). With the exception of Oman, Libya and Djibouti, significantly more males than females ate F&V ≥5 times/d. Proportion of students consuming F&V ≥5 times/d also varied significantly in all counties based on BMI (P<0·0001), with students within normal BMI having the highest frequency. A negative trend was observed between age and the prevalence of taking F&V ≥5 times/d in most of the eleven EMR countries but Jordan, Djibouti and Morocco. The prevalence of adequate intake of F&V was low in the eleven EMR countries. There is a need for interventions to increase the prevalence of adolescents consuming F&V ≥5 times/d. Interventions should take into consideration psychosocial, environmental and socio-environmental factors influencing F&V intake within countries.


Assuntos
Fenômenos Fisiológicos da Nutrição do Adolescente , Dieta , Frutas , Política Nutricional , Cooperação do Paciente , Verduras , Adolescente , Fenômenos Fisiológicos da Nutrição do Adolescente/etnologia , África Oriental , África do Norte , Ásia Ocidental , Criança , Fenômenos Fisiológicos da Nutrição Infantil , Estudos Transversais , Dieta/etnologia , Feminino , Humanos , Masculino , Região do Mediterrâneo , Oriente Médio , Inquéritos Nutricionais , Cooperação do Paciente/etnologia , Instituições Acadêmicas
13.
Clin Radiol ; 71(10): 1037-1043, 2016 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-27083056

RESUMO

AIM: To analyse the value of targeted second-look ultrasound and imaging-guided biopsy in high-risk young women eligible for screening magnetic resonance imaging (MRI) in a tertiary referral centre in Perth, Western Australia. MATERIALS AND METHODS: A retrospective analysis of eligible high-risk young women who underwent screening breast MRI and targeted second-look ultrasound between June 2012 and June 2014 was performed with review of data. RESULTS: Over a 2-year period, 139 women underwent high-risk screening MRI. Of these, 30 women (with a total of 45 lesions) were recalled for targeted second-look ultrasound. Thirty-four MRI-detected lesions were identified on targeted ultrasound with 19 of them proceeding to ultrasound-guided biopsy, while the remaining 15 lesions were considered benign on ultrasound, were not biopsied, and were stable on follow-up imaging 12 months later. One lesion proceeded to an MRI-guided biopsy to confirm a benign result. Of the 11 lesions not seen on ultrasound, nine underwent MRI biopsy, one proceeded directly to hook wire localisation and excision, and one did not return for biopsy and was lost to follow-up. The overall biopsy rate was 14.4%. The cancer detection rate was 1.4%. CONCLUSION: The results of this study indicate that targeted second-look ultrasound and ultrasound-guided biopsy is a cost-effective and time-efficient approach for MRI-detected lesions in young women at high risk of developing breast cancer. MRI-guided biopsy should be considered for ultrasonographically occult suspicious lesions as there is a low, but definite, risk of cancer.


Assuntos
Neoplasias da Mama/diagnóstico por imagem , Neoplasias da Mama/patologia , Imageamento por Ressonância Magnética/métodos , Ultrassonografia Mamária/métodos , Adulto , Mama/diagnóstico por imagem , Mama/patologia , Feminino , Seguimentos , Humanos , Biópsia Guiada por Imagem , Reprodutibilidade dos Testes , Estudos Retrospectivos , Risco , Austrália Ocidental
14.
Indoor Air ; 26(5): 734-42, 2016 10.
Artigo em Inglês | MEDLINE | ID: mdl-26547489

RESUMO

Indoor air pollution has been linked to adverse chronic obstructive pulmonary disease (COPD) health, but specific causative agents have not yet been identified. We evaluated the role of indoor endotoxin exposure upon respiratory health in former smokers with COPD. Eighty-four adults with moderate to severe COPD were followed longitudinally and indoor air and dust samples collected at baseline, 3 and 6 months. Respiratory outcomes were repeatedly assessed at each time point. The associations between endotoxin exposure in air and settled dust and health outcomes were explored using generalizing estimating equations in multivariate models accounting for confounders. Dust endotoxin concentrations in the main living area were highest in spring and lowest in fall, while airborne endotoxins remained steady across seasons. Airborne and dust endotoxin concentrations were weakly correlated with one another (rs  = +0.24, P = 0.005). Endotoxin concentrations were not significantly associated with respiratory symptoms, rescue medication use, quality of life, or severe exacerbations. In vitro whole-blood assays of the pro-inflammatory capacity of PM10 filters with and without endotoxin depletion demonstrated that the endotoxin component of indoor air pollution was not the primary trigger for interleukin-1ß release. Our findings support that endotoxin is not the major driver in the adverse effects of indoor PM upon COPD morbidity.


Assuntos
Poluição do Ar em Ambientes Fechados/análise , Poeira/análise , Endotoxinas/análise , Exposição Ambiental/análise , Doença Pulmonar Obstrutiva Crônica/etiologia , Fumar/efeitos adversos , Idoso , Poluição do Ar em Ambientes Fechados/efeitos adversos , Exposição Ambiental/efeitos adversos , Feminino , Habitação , Humanos , Estudos Longitudinais , Masculino , Pessoa de Meia-Idade , Estações do Ano , Fatores de Tempo
15.
Ann Surg Oncol ; 22 Suppl 3: S422-7, 2015 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-26310280

RESUMO

BACKGROUND: This study aimed to evaluate the impact that the release of consensus guidelines for margins in breast-conserving surgery (BCS) had on re-excision rates. METHODS: A retrospective review examined a prospectively maintained database of patients who had operable invasive breast cancer treated with BCS at the authors' institution. The patients were divided into two groups: (1) those with a diagnosis determined from 1 July 2011 to 31 July 2013 (before release of the guidelines) and (2) those with a diagnosis determined from 1 February 2014 to 31 July 2014 (after release of the guidelines). The groups were evaluated with respect to patient and tumor characteristics, re-excision rates, and reasons for re-excision. RESULTS: A total of 846 cases of BCS were managed: 597 in group 1 and 249 in group 2. Re-excision rates were significantly reduced after release of the consensus guidelines (p = 0.03). Re-excisions were performed for 115 (19 %) of 597 patients in group 1 and 32 (13 %) of 249 patients in group 2. After release of the guidelines, re-excisions were performed for positive margins, as defined by the consensus statement, in 25 (78 %) of 32 cases. The two groups did not differ significantly in terms of age, tumor size, grade, nodal status, estrogen receptor status, progesterone receptor status, or human epidermal growth factor receptor 2 status. Group 1 had more tumors of mixed ductal and lobular histology than group 2, and group 2 had more lobular tumors than group 1 (p = 0.02). CONCLUSIONS: The consensus guidelines on margins for BCS were applied for 78 % of the patients who underwent re-excision and resulted in a significant reduction in re-excision rates.


Assuntos
Neoplasias da Mama/cirurgia , Carcinoma Ductal de Mama/cirurgia , Carcinoma Lobular/cirurgia , Mastectomia Segmentar , Neoplasia Residual/cirurgia , Guias de Prática Clínica como Assunto/normas , Biomarcadores Tumorais/metabolismo , Neoplasias da Mama/metabolismo , Neoplasias da Mama/patologia , Carcinoma Ductal de Mama/metabolismo , Carcinoma Ductal de Mama/patologia , Carcinoma Lobular/metabolismo , Carcinoma Lobular/patologia , Conferências de Consenso como Assunto , Feminino , Seguimentos , Humanos , Técnicas Imunoenzimáticas , Oncologia , Pessoa de Meia-Idade , Gradação de Tumores , Invasividade Neoplásica , Estadiamento de Neoplasias , Neoplasia Residual/metabolismo , Neoplasia Residual/patologia , Prognóstico , Estudos Prospectivos , Radioterapia (Especialidade)/normas , Receptor ErbB-2/metabolismo , Receptores de Estrogênio/metabolismo , Receptores de Progesterona/metabolismo , Estudos Retrospectivos
16.
Phys Rev Lett ; 113(6): 062001, 2014 Aug 08.
Artigo em Inglês | MEDLINE | ID: mdl-25148317

RESUMO

New data on the polarization observables T, P, and H for the reaction γp→pπ(0) are reported. The results are extracted from azimuthal asymmetries when a transversely polarized butanol target and a linearly polarized photon beam are used. The data were taken at the Bonn electron stretcher accelerator ELSA using the CBELSA/TAPS detector. These and earlier data are used to perform a truncated energy-independent partial wave analysis in sliced-energy bins. This energy-independent analysis is compared to the results from energy-dependent partial wave analyses.

17.
Phys Rev Lett ; 112(1): 012003, 2014 Jan 10.
Artigo em Inglês | MEDLINE | ID: mdl-24483889

RESUMO

The first measurement of the helicity dependence of the photoproduction cross section of single neutral pions off protons is reported for photon energies from 600 to 2300 MeV, covering nearly the full solid angle. The data are compared to predictions from the SAID, MAID, and BnGa partial wave analyses. Strikingly large differences between data and predictions are observed, which are traced to differences in the helicity amplitudes of well-known and established resonances. Precise values for the helicity amplitudes of several resonances are reported.

19.
Placenta ; 154: 66-73, 2024 Jun 07.
Artigo em Inglês | MEDLINE | ID: mdl-38905849

RESUMO

INTRODUCTION: Recurrent pregnancy loss (RPL) is defined as the spontaneous loss of two or more consecutive pregnancies before 20 weeks of gestation, and affects 7.46 % of the Indian population. About 40-50 % of RPL cases are idiopathic making it a therapeutic challenge for clinicians. This study focuses on elucidating the role of hypoxia-associated placental angiogenesis in these idiopathic RPL cases. METHODS: Whole blood and product of conception (POCs) were collected from RPL patients (N = 87) and cases of voluntary abortions (medically terminated pregnancy, MTP; n = 110) as controls with informed consent. Serum separated from whole blood was used to study the ROS-antioxidant status in the cases and controls through colorimetric assays and ELISA. The mRNA extracted from placental tissue samples were used to determine the hypoxic and angiogenic status in cases and controls through real time PCR. Statistical analysis was also carried out to correlate the differential hypoxic status between RPL and MTP cohorts with the expression of angiogenic factors (VEGFA, VEGFR1 and VEGFR2). RESULTS: HIF1α mRNA expression was found to be upregulated in the RPL cases. While the serum levels of H2O2 (p = 0.012), guanine oxides and lipid hydroperoxides (LPO) were increased in the RPL cases, reduced glutathione (GSH) was found to be significantly decreased (p = 0.012). Additionally, AUROC analysis also shows an excellent discriminatory ability of 0.850 for serum H2O2 levels. VEGF-A and VEGF-R1 mRNA expression was also found to be downregulated in the RPL cases compared to MTP. DISCUSSION: This study indicates that increased oxidative stress may lead to aberrations in the VEGF pathway resulting in improper placentation in RPL cases, and subsequently, pregnancy loss.

20.
Mymensingh Med J ; 33(3): 736-740, 2024 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-38944715

RESUMO

Parieto-occipital sulcus is one of the major sulcus of the cerebral hemisphere which separates the occipital lobe from the parietal lobe. Morphology of this sulcus varies with age, sex, manual skill, handedness and in many diseases. For various clinical investigations and surgery, detailed morphological knowledge of this sulcus is very much essential for the surgeons and radiologists. This study is carried out to establish a normal standard in length of the parieto-occipital sulcus in different age and sex groups of Bangladeshi people. A cross-sectional, descriptive type of study was conducted in the department of Anatomy, Mymensingh Medical College, Bangladesh from July 2016 to July 2017. About 60 specimens were collected from medico-legal cases and divided into four age groups including, Group A (20-29 years), Group B (30-39 years), Group C (40-49 years) and Group D (50 years and above). The mean length of parieto-occipital sulcus was 3.92±0.559cm to 3.29±0.434 cm in male and 3.81±0.715cm to 3.03±0.551cm in female. The difference in mean length of the parieto-occipital sulcus for both left and right hemisphere between male and female was statistically non-significant in all age groups. For statistical analysis, differences between age and sex groups were analyzed by using students unpaired 't' test. In this study, the length of the parieto-occipital sulcus showed gradual decreasing values with advancing age.


Assuntos
Lobo Occipital , Lobo Parietal , Humanos , Feminino , Masculino , Adulto , Bangladesh , Estudos Transversais , Lobo Occipital/anatomia & histologia , Pessoa de Meia-Idade , Adulto Jovem , Lobo Parietal/anatomia & histologia , Fatores Etários , Fatores Sexuais , População do Sul da Ásia
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