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1.
Mymensingh Med J ; 33(1): 279-285, 2024 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-38163804

RESUMEN

Identification is one of the most important aspects of mass disasters. Stature estimation is an essential parameter for identification and is widely used in forensic anthropology, where DNA facility is limited. A hand is most studied part of the upper limb; however, data are scarce concerning particular geographical populations. This study is an effort to provide tangible data for such forensic investigations. It was a prospective, cross-sectional study on 500 medicolegal death cases brought for post-mortem examination. It aimed to estimate stature in the Northwest population using hand and finger measurements of dead persons by mathematical models. A total of seven parameters in hand were used to generate linear and multiple regression equations, correlation coefficients and finger indexes for stature estimation and sex differentiation. The correlation coefficient between stature and all the hand measurements were significant except for the index and middle finger on both sides in females. Bilateral differences were insignificant for hand length and breath, except for the middle finger length in both sexes and length of thumb in females. Multiple regression equations for stature estimation were better than linear regression equations for stature estimation. SEE ranged from 4.31 to 6.26 in males and 4.11 to 5.25 in females. For identification, hand length is the best individual parameter among other hand measurements. The measurement accuracy and practical aspects can be enhanced if we consider cadaveric participants. The multiple regression model approach can give a fair estimate of the stature of the deceased.


Asunto(s)
Mano , Incidentes con Víctimas en Masa , Masculino , Femenino , Humanos , Estudios Transversales , Estudios Prospectivos , Extremidad Superior
2.
BMC Pregnancy Childbirth ; 23(1): 823, 2023 Nov 28.
Artículo en Inglés | MEDLINE | ID: mdl-38017404

RESUMEN

BACKGROUND: The United Kingdom (UK) has committed to the World Health Organization's viral hepatitis elimination targets. New case finding strategies, such as antenatal testing, may be needed to achieve these targets. We conducted a rapid review to understand hepatitis C-specific antibody (anti-HCV) and HCV RNA test positivity in antenatal settings in the United Kingdom to inform guidance. METHODS: Articles and conference abstracts published between January 2000 and June 2022 reporting anti-HCV testing in antenatal settings were identified through PubMed and Web of Science searches. Results were synthesised using a narrative approach. RESULTS: The search identified 2,011 publications; 10 studies were included in the final synthesis. Seven studies used anonymous testing methods and three studies used universal opt-out testing. Anti-HCV test positivity ranged from 0.1 to 0.99%, with a median value of 0.38%. Five studies reported HCV RNA positivity, which ranged from 0.1 to 0.57% of the testing population, with a median value of 0.22%. One study reported cost effectiveness of HCV and found it to be cost effective at £9,139 per quality adjusted life years. CONCLUSION: The relative contribution of universal opt-out antenatal testing for HCV should be reconsidered, as antenatal testing could play an important role in new case-finding and aid achieving elimination targets.


Asunto(s)
Hepacivirus , Hepatitis C , Humanos , Femenino , Embarazo , Hepatitis C/diagnóstico , Hepatitis C/epidemiología , Diagnóstico Prenatal , Análisis Costo-Beneficio , ARN , Reino Unido
3.
Science ; 381(6660): 867-872, 2023 Aug 25.
Artículo en Inglés | MEDLINE | ID: mdl-37616348

RESUMEN

Coronal holes are areas on the Sun with open magnetic field lines. They are a source region of the solar wind, but how the wind emerges from coronal holes is not known. We observed a coronal hole using the Extreme Ultraviolet Imager on the Solar Orbiter spacecraft. We identified jets on scales of a few hundred kilometers, which last 20 to 100 seconds and reach speeds of ~100 kilometers per second. The jets are powered by magnetic reconnection and have kinetic energy in the picoflare range. They are intermittent but widespread within the observed coronal hole. We suggest that such picoflare jets could produce enough high-temperature plasma to sustain the solar wind and that the wind emerges from coronal holes as a highly intermittent outflow at small scales.

4.
Mymensingh Med J ; 32(3): 888-892, 2023 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-37391991

RESUMEN

Among other valvular heart disease Aortic stenosis (AS) is the most common in the developed world. Transcatheter Aortic Valve Replacement (TAVR) is most acceptable treatment option for patient with severely calcified aortic stenosis with high and intermediate risk group. Among several challenges, one of the main challenges is to deal with bicuspid aortic valve (BAV). Non-circular annulus, bulky leaflets leading to perivalvular leaks and risk for rupture and often very severe calcification may contribute to periprocedural strokes leading to poor clinical outcome. This case, a 68-year-old woman with a history of type 2 diabetes mellitus (DM), hypothyroidism, bicuspid aortic valve and severe aortic stenosis, bronchial asthma, who had repeatedly refused any suggestion for open heart surgery, was our volunteer candidate for TAVR. After successful TAVR the peak pressure gradient decreased from 100mmHg to 17mmHg. So, TAVR could be a viable option for highly selected patients with severe aortic stenosis and bicuspid aortic valve who have favourable anatomy.


Asunto(s)
Estenosis de la Válvula Aórtica , Asma , Enfermedad de la Válvula Aórtica Bicúspide , Diabetes Mellitus Tipo 2 , Reemplazo de la Válvula Aórtica Transcatéter , Femenino , Humanos , Anciano , Estenosis de la Válvula Aórtica/complicaciones , Estenosis de la Válvula Aórtica/cirugía
5.
Phys Rev Lett ; 131(2): 023001, 2023 Jul 14.
Artículo en Inglés | MEDLINE | ID: mdl-37505945

RESUMEN

Ionization of matter by energetic radiation generally causes complex secondary reactions that are hard to decipher. Using large helium nanodroplets irradiated by extreme ultraviolet (XUV) photons, we show that the full chain of processes ensuing primary photoionization can be tracked in detail by means of high-resolution electron spectroscopy. We find that elastic and inelastic scattering of photoelectrons efficiently induces interatomic Coulombic decay (ICD) in the droplets. This type of indirect ICD even becomes the dominant process of electron emission in nearly the entire XUV range in large droplets with radius ≳40 nm. Indirect ICD processes induced by electron scattering likely play an important role in other condensed-phase systems exposed to ionizing radiation as well, including biological matter.

6.
Nature ; 613(7945): 662-666, 2023 01.
Artículo en Inglés | MEDLINE | ID: mdl-36697865

RESUMEN

Field emission of electrons underlies great advances in science and technology, ranging from signal processing at ever higher frequencies1 to imaging of the atomic-scale structure of matter2 with picometre resolution. The advancing of electron microscopy techniques to enable the complete visualization of matter on the native spatial (picometre) and temporal (attosecond) scales of electron dynamics calls for techniques that can confine and examine the field emission on sub-femtosecond time intervals. Intense laser pulses have paved the way to this end3,4 by demonstrating femtosecond confinement5,6 and sub-optical cycle control7,8 of the optical field emission9 from nanostructured metals. Yet the measurement of attosecond electron pulses has remained elusive. We used intense, sub-cycle light transients to induce optical field emission of electron pulses from tungsten nanotips and a weak replica of the same transient to directly investigate the emission dynamics in real time. Access to the temporal properties of the electron pulses rescattering off the tip surface, including the duration τ = (53 as ± 5 as) and chirp, and the direct exploration of nanoscale near fields open new prospects for research and applications at the interface of attosecond physics and nano-optics.

7.
Ann R Coll Surg Engl ; 105(4): 323-330, 2023 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-35617107

RESUMEN

INTRODUCTION: Emphysematous pyelonephritis (EPN) is a deadly disease due to its associated morbidity and mortality. Attempts have been made to identify predictors of severity, mortality and need for nephrectomy in EPN with little success. METHODS: We conducted an ambispective study of EPN patients between March 2014 and September 2019. Retrospective data were collected which included age, sex, comorbidities, symptoms, signs, laboratory investigations including imaging, need for dialysis, management and any complications. All patients were then followed prospectively for renal dynamic scan, stone surgery or nephrectomy. Univariate analysis was performed to identify factors affecting mortality and need for elective nephrectomy. RESULTS: In total, 112 patients were included. Mean patient age was 50.01 years, 55% were female and 5% had bilateral involvement. Fever and flank pain were the most common symptoms. Diabetes was seen in 75% of cases and 30% of cases required haemodialysis at initial presentation. About 60% of patients improved with pigtail drainage. Need for nephrectomy was greater in Huang-Tseng stage 3a (14.8%). Huang-Tseng stages 3b and 4 had higher mortality rates (25%) than the other stages (2.2%). Twelve of 99 patients had non functional kidney on follow-up and underwent elective nephrectomy. Low platelet counts, high body mass index, septic shock, dialysis and higher Huang-Tseng stage were found to be predictive of mortality and renal parenchymal thickness on computed tomography scan was predictive of follow-up nephrectomy. CONCLUSIONS: Thrombocytopaenia, high body mass index, septic shock, haemodialysis and higher Huang-Tseng stage are predictors of mortality and renal parenchymal thickness <5mm is a predictor of poor salvage of affected kidney on follow-up.


Asunto(s)
Complicaciones de la Diabetes , Enfisema , Pielonefritis , Choque Séptico , Humanos , Femenino , Persona de Mediana Edad , Masculino , Resultado del Tratamiento , Estudios Retrospectivos , Centros de Atención Terciaria , Choque Séptico/complicaciones , Choque Séptico/cirugía , Pielonefritis/complicaciones , Pielonefritis/cirugía , Nefrectomía/efectos adversos , Complicaciones de la Diabetes/complicaciones , Enfisema/complicaciones , Enfisema/cirugía
9.
Biometrics ; 79(3): 1701-1712, 2023 09.
Artículo en Inglés | MEDLINE | ID: mdl-36471903

RESUMEN

We propose and study a simple and innovative non-parametric approach to estimate the age-of-onset distribution for a disease from a cross-sectional sample of the population that includes individuals with prevalent disease. First, we estimate the joint distribution of two event times, the age of disease onset and the survival time after disease onset. We accommodate that individuals had to be alive at the time of the study by conditioning on their survival until the age at sampling. We propose a computationally efficient expectation-maximization (EM) algorithm and derive the asymptotic properties of the resulting estimates. From these joint probabilities we then obtain non-parametric estimates of the age-at-onset distribution by marginalizing over the survival time after disease onset to death. The method accommodates categorical covariates and can be used to obtain unbiased estimates of the covariate distribution in the source population. We show in simulations that our method performs well in finite samples even under large amounts of truncation for prevalent cases. We apply the proposed method to data from female participants in the Washington Ashkenazi Study to estimate the age-at-onset distribution of breast cancer associated with carrying BRCA1 or BRCA2 mutations.


Asunto(s)
Edad de Inicio , Humanos , Femenino , Estudios Transversales , Probabilidad , Causalidad , Washingtón
10.
Sci Rep ; 12(1): 20372, 2022 11 27.
Artículo en Inglés | MEDLINE | ID: mdl-36437267

RESUMEN

Kinship analysis in forensics is based on the calculation of the respective kinship indices. However, this calculation is only possible when the subject under identification has been associated with a particular population, whose allele frequency data is available for the particular set of STR markers used in the forensic practices. In the case of mass disasters, where a large number of individuals are to be identified, gathering the population frequency data and calculating the kinship indices can be an intricate process which requires a lot of time and huge resources. The new method of allele matching cut off score (AMCOS) developed in this study is based on the allele sharing approach. This approach simply refers to the number of shared alleles (1 or 2) between the two individuals; also known as identical by state (IBS) alleles which might have been inherited from a recent common ancestor in which the alleles are identical by descendent (IBD). In case of mass disasters, this method can be used to narrow down the number of pairs (dead and alive) to be matched for kinship without using the allele frequency data. The results obtained from this method could further be confirmed by LR based method, which uses the allele frequency data of the respective population of the pairs being tested for kinship. AMCOS method has been tested for its sensitivity, specificity and various other statistical parameters and has shown promising values for the same in various types of kinship analyses. This ascertains the authenticity and potential use of this method in forensic practice but only after its validation in a larger sample size. AMCOS method has been tested on siblings and grandparent-grandchildren by using autosomal and X-STR markers both, as the reference samples from the parents cannot always be available for the identification. The present study also compared the results shown by the autosomal and X-STR markers in siblings and grandparent-grandchildren identification, thereby suggesting the use of better set of markers on the basis of obtained values of various statistical parameters.


Asunto(s)
Dermatoglifia del ADN , Desastres , Humanos , Dermatoglifia del ADN/métodos , Prueba de Estudio Conceptual , Frecuencia de los Genes , Alelos
11.
Phys Chem Chem Phys ; 24(47): 28844-28852, 2022 Dec 07.
Artículo en Inglés | MEDLINE | ID: mdl-36422471

RESUMEN

Superfluid helium nanodroplets are often considered as transparent and chemically inert nanometer-sized cryo-matrices for high-resolution or time-resolved spectroscopy of embedded molecules and clusters. On the other hand, when the helium nanodroplets are resonantly excited with XUV radiation, a multitude of ultrafast processes are initiated, such as relaxation into metastable states, formation of nanoscopic bubbles or excimers, and autoionization channels generating low-energy free electrons. Here, we discuss the full spectrum of ultrafast relaxation processes observed when helium nanodroplets are electronically excited. In particular, we perform an in-depth study of the relaxation dynamics occurring in the lowest 1s2s and 1s2p droplet bands using high resolution, time-resolved photoelectron spectroscopy. The simplified excitation scheme and improved resolution allow us to identify the relaxation into metastable triplet and excimer states even when exciting below the droplets' autoionization threshold, unobserved in previous studies.

12.
Int J Tuberc Lung Dis ; 26(11): 1033-1040, 2022 Nov 01.
Artículo en Inglés | MEDLINE | ID: mdl-36281040

RESUMEN

INTRODUCTION: Patients with isoniazid (H, INH) resistant pulmonary TB but undetected rifampicin (R, RIF) resistance are treated with a 6-month regimen of levofloxacin-RIF-ethambutol-pyrazinamide (6LvxREZ) under India´s National TB Elimination Programme (NTEP).OBJECTIVE: To describe the profile of and treatment outcomes in patients with pulmonary INH-resistant (INHR) TB initiated on TB treatment, and identify factors associated with unfavourable treatment outcomes (died, failed, treatment changed, lost to follow-up).METHODS: This was a retrospective analysis of NTEP database (Ni-kshay) on pulmonary INHR TB patients initiated on treatment with "H mono/poly regimen" (6LvxREZ) between July 2019 and June 2020 with documented treatment outcomes. Proportions with 95% confidence interval (CI) was calculated and logistic regression analysis was performed.RESULTS: Of the 11,519 patients with pulmonary INHR TB, 9,440 (82%) had treatment success (55.1% cured, 26.9% treatment completed). Unfavourable treatment outcome was observed in 1,901 (16.5%). Male sex, tobacco and alcohol use, HIV reactive status were associated with unfavourable treatment outcome. Patients with katG mutations and resistance to fluoroquinolones were likely to have poor treatment outcomes.CONCLUSION: A levofloxacin-based regimen offers a treatment success rate of 82% in patients with pulmonary INHR TB. Sex-specific strategies, interventions to address smoking and alcohol use, focus on HIV-reactive patients and optimising treatment regimens based on drug susceptibility should be considered for improving treatment outcomes.


Asunto(s)
Infecciones por VIH , Tuberculosis Pulmonar , Femenino , Humanos , Masculino , Isoniazida/uso terapéutico , Pirazinamida/uso terapéutico , Etambutol/uso terapéutico , Rifampin/uso terapéutico , Levofloxacino/uso terapéutico , Estudios Retrospectivos , Tuberculosis Pulmonar/tratamiento farmacológico , Fluoroquinolonas/uso terapéutico , Resultado del Tratamiento , Infecciones por VIH/epidemiología , Infecciones por VIH/tratamiento farmacológico
13.
Sci Rep ; 12(1): 16508, 2022 Oct 03.
Artículo en Inglés | MEDLINE | ID: mdl-36192489

RESUMEN

In this report, the effect of rare-earth (RE3+) ion substitution on structural, microstructural, and electrical properties in barium bismuth titanate (BaBi4Ti4O15) (BBTO) Aurivillius ceramics has been investigated. The Rietveld refinements on X-ray diffraction (XRD) patterns confirm that all the samples have an orthorhombic crystal system with A21am space group. Meanwhile, temperature dependent synchrotron XRD patterns reveal that the existence of dual phase in higher temperature region. The randomly oriented plate-like grains are experimentally strived to confirm the distinctive feature of bismuth layered Aurivillius ceramics. The broad band dielectric spectroscopic investigation signifies a shifting of ferroelectric phase transition (Tm) towards low temperature region with a decrease of the RE3+-ionic radii in BBTO ceramics. The origin of diffuse ferroelectric phase transitions followed by stabilization of the relaxor ferroelectric nature at high frequency region is explained using suitable standard models. The temperature dependent ac and dc conductivity results indicate the presence of double ionized oxygen vacancies in BBTO ceramics, whereas the dominance of single ionized oxygen vacancies is observed in RE-substituted BBTO ceramics. The room temperature polarization vs. electric field (P-E) hysteresis loops are shown to be well-shaped symmetric for BBTO ceramics, whereas slim asymmetric ferroelectric characteristics developed at RE-substituted BBTO ceramics.

14.
Environ Monit Assess ; 194(9): 643, 2022 Aug 05.
Artículo en Inglés | MEDLINE | ID: mdl-35930070

RESUMEN

The present study demonstrates the spatial analysis and mapping of fish and different measures of environmental parameters and fish diversity of Pong reservoir, Himachal Pradesh, using Kriging spatial interpolation methods for geographical information system mapping. Seasonal data on environmental parameters, potential fish habitat and fish diversity was collected from lentic (dam), lentic (reservoir), transitional and lotic zone of the reservoir.. Important environmental parameters like water temperature, dissolved oxygen, electrical conductivity, water depth and transparency showed variations across the different zones of the reservoir. The sediment of the reservoir was sandy clay loam in nature as per texture analysis. Fish species richness, Shannon index and evenness index showed a similarity of the lotic and lentic (reservoir) zones of the reservoir. Six potential fish breeding grounds were identified in the reservoir indicating high conservation significance. The analysis of data showed a declining trend in fish production from 456.9 tonnes during the decade 1976-1987 to 347.91 tonnes during 2009-2020. The factors like anthropogenic climate change, predation of a stocked fish juvenile by water birds, undersized fish stocking and unscientific management are the probable reasons for the decreasing fish production. The spatial variation pattern of the water spread area, environmental parameters, fish catch and potential fish breeding grounds depicted in the GIS platform can be used as an important information base by the policy makers for fisheries management. The stocking of large size fish as a stocking material and adequate protection of the potential fish breeding grounds are the key advisories for the sustainable enhancement of fisheries as well as conservation.


Asunto(s)
Biodiversidad , Sistemas de Información Geográfica , Animales , Ecosistema , Monitoreo del Ambiente , Peces , Agua
15.
New Microbes New Infect ; 48: 100999, 2022 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-35873064

RESUMEN

Background: Antibiotic-resistance in E. coli is a global issue affecting humans especially the pediatric population. Antibiotic-resistant E. coli is a pathogen frequently pediatric population as well as healthy adults. Methods: This study aimed to examine the antibiotic resistance of E. coli causing pediatric diarrhea and its drug-resistant rates, its adhering abilities to cell line in vitro, and inhibition efficiency of a few selected chemical compounds. Clinical strains were isolated from both the healthy and infected pediatric population of Mizoram. Results: Adhesion is a significant pathogenic process during bacterial infections, which has been employed for pathotyping of DEC by comparing adhesion efficiency in both normal (CHO-k1) and cancer (HeLa) cell lines. E. coli adherent pathotypes were identified by both PCR assay and in-vitro cell adhesion assays; the study also evaluated the adhesion inhibition ability of human skimmed milk, gentamicin, and cephalexin in-vitro. Of all isolates, 20.05% of adherent DEC (EPEC, DAEC, and EIEC) and 11.39 % of non-adherent DEC (STEC and ETEC) were found to be associated with pediatric diarrhoea in Mizoram. Human skimmed milk has a high potential adhesion inhibition against EAEC (50.25/90.90 µg/mL), EPEC (53.42/259.70 µg/mL), and EIEC (59.13/30.30 µg/mL) in both cell lines in comparison with gentamicin and cephalexin. Conclusion: This study concludes that as a dietary supplement-human skimmed milk has high potential to prevent adhesion of DEC pathotypes in cells in-vitro thus in in-vivo.

16.
J Hosp Infect ; 126: 37-43, 2022 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-35427722

RESUMEN

BACKGROUND: Disinfectant wipes containing quaternary ammonium compounds (QACs) are widely used within health care. Viscose remains a popular material for these products, although limited information is available concerning its impact on performance against biofilms when compared with alternatives. AIM: To identify disinfectant wipe materials and surface properties which optimize product performance against biofilms. METHODS: Biofilm eradication performance of two commercial viscose-QAC wipes was determined against Staphylococcus aureus and Acinetobacter baumannii dry surface biofilms (DSBs) using an ASTM E2967-based procedure. Additionally, five materials were impregnated with a commercial liquid formulation containing didecyldimethylammonium chloride (DDAC). Following 24 h of storage, eradication performance and DDAC content of extracted liquid were determined and compared with material properties, including zeta potential, hydrophobicity and surface area. FINDINGS: Under stringent test conditions, eradication of DSBs by commercial products was no greater than equivalent materials impregnated with water. Extract from one viscose-based product contained 89% less DDAC than the impregnation solution, indicating extensive adsorption. Of the other tested materials, viscose performed worst; nearly 70% of DDAC had depleted from material extracts within 24 h. In contrast, DDAC depletion from polypropylene extracts was only 25%, and DSB eradication was >100 times greater than viscose. Biofilm eradication performance against both species correlated with the DDAC content of extracts, which, in turn, correlated with zeta potential and hydrophobicity. CONCLUSION: Biofilm eradication performance of QAC-based wipes was significantly greater when selecting thermoplastic substrates over viscose. However, these materials are non-sustainably sourced and non-biodegradable. This study highlights a need to develop new wipe products that are more effective against biofilms.


Asunto(s)
Desinfectantes , Compuestos de Amonio Cuaternario , Adsorción , Biopelículas , Desinfectantes/química , Desinfectantes/farmacología , Humanos , Compuestos de Amonio Cuaternario/farmacología , Staphylococcus aureus
17.
Phys Chem Chem Phys ; 24(5): 2944-2957, 2022 Feb 02.
Artículo en Inglés | MEDLINE | ID: mdl-35076648

RESUMEN

The fragmentation dynamics of the gas-phase, doubly charged camphor molecule, formed by Auger decay following carbon 1s ionisation, using soft X-ray synchrotron radiation, is presented in this work. The technique of velocity map imaging combined with a photoelectron-photoion-photoion coincidence (VMI-PEPIPICO) is used for both electron energy and ion momentum (in-sequence) measurements. The experimental study is complemented by molecular dynamics simulation, performed with an NVT (moles, volume, and temperature) ensemble. Velocity Verlet algorithms were used for time integration at various internal energies. These simulations validate observed dissociation pathways. From these, we successfully deduce that the internal energy of the doubly charged molecular ion has a significant contribution to the fragmentation mechanism. Notably, a prominent signature of the internal energy was observed in the experimentally determined energies of the neutral fragment in these deferred charge separation pathways, entailing a more detailed theoretical study to uncover the exact dissociation dynamics.

18.
Ann R Coll Surg Engl ; 104(6): e168-e170, 2022 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-34939847

RESUMEN

Renal cell cancer (RCC) commonly presents as an asymptomatic incidental mass on imaging for other abdominal pathologies. Because of its hypervascular nature, spontaneous haemorrhage, although very rare, can be seen with RCC. Spontaneous haemorrhage may present with flank pain, fever and sudden abdominal distension with or without haemorrhagic shock. Although unusual, spontaneous haemorrhage is potentially serious, and therefore clinicians should be aware of such events. Imaging may be difficult to interpret in view of intratumoral and perinephric haemorrhage. Prompt diagnosis and treatment is essential for a successful outcome. We report a case of massive intratumoral bleed in RCC in a young male and its management by renal artery angioembolisation followed by radical nephrectomy.


Asunto(s)
Carcinoma de Células Renales , Neoplasias Renales , Carcinoma de Células Renales/complicaciones , Carcinoma de Células Renales/cirugía , Dolor en el Flanco/etiología , Hemorragia/diagnóstico por imagen , Hemorragia/etiología , Hemorragia/terapia , Humanos , Neoplasias Renales/complicaciones , Neoplasias Renales/diagnóstico por imagen , Neoplasias Renales/cirugía , Masculino , Nefrectomía/métodos
19.
Sci Total Environ ; 780: 146379, 2021 Aug 01.
Artículo en Inglés | MEDLINE | ID: mdl-33773349

RESUMEN

The role of mangroves in sequestering metal and nutrients in sediment has been described in the past, but knowledge gaps still exist on storage capacity and recycling fluxes of elements in plant biomass, notably concerning their magnitude in root uptake and loss by litterfall. This study addresses the storage and transport pathways of 16 elements, classified as macro-nutrients (Ca, Mg, Na, K), micro-nutrients (Fe, Mn, Ni, Co, Cu, Cr, Zn, Mo), and potential toxicants (Al, Cd, Sn, Pb) in the world's largest mangroves, the Sundarbans. Elemental concentrations in plant organs were generally lower than in the sediment. The stock of macro and micro-nutrients in plant biomass varied from 60 to 2717 and 0.003 to 37.7 Mg ha-1 respectively, with highest values observed for Na and lowest for Cd. The Avicennia species exhibited the maximal accumulation of all elements. Translocation of major elements to different plant organs increased with increasing their concentrations in the sediment. Elemental loss via litterfall indicated that Sundarbans mangrove could act as a source, particularly of Mn, to the Bay of Bengal. Moreover, belowground uptake of the 16 elements showed 2-3 fold higher fluxes than their loss via litterfall. There was a significant retention of some trace elements (notably Mo, Cd, and Sn) in plant biomass, which might allow one to use these mangroves for phytoremediation and restoration purposes. We conclude that mangroves efficiently store and remobilize major and trace elements from the sediments by root uptake and recycle back to sediment surface via litterfall.


Asunto(s)
Avicennia , Metales Pesados , Oligoelementos , Contaminantes Químicos del Agua , Monitoreo del Ambiente , Sedimentos Geológicos , Metales Pesados/análisis , Oligoelementos/análisis , Contaminantes Químicos del Agua/análisis , Humedales
20.
Faraday Discuss ; 228(0): 242-265, 2021 May 27.
Artículo en Inglés | MEDLINE | ID: mdl-33687396

RESUMEN

The acetylene-vinylidene system serves as a benchmark for investigations of ultrafast dynamical processes where the coupling of the electronic and nuclear degrees of freedom provides a fertile playground to explore the femto- and sub-femto-second physics with coherent extreme-ultraviolet (EUV) photon sources both on the table-top as well as free-electron lasers. We focus on detailed investigations of this molecular system in the photon energy range 19-40 eV where EUV pulses can probe the dynamics effectively. We employ photoelectron-photoion coincidence (PEPICO) spectroscopy to uncover hitherto unrevealed aspects of this system. In this work, the role of excited states of the C2H2+ cation, the primary photoion, is specifically addressed. From photoelectron energy spectra and angular distributions, the nature of the dissociation and isomerization channels is discerned. Exploiting the 4π-collection geometry of the velocity map imaging spectrometer, we not only probe pathways where the efficiency of photoionization is inherently high but also perform PEPICO spectroscopy on relatively weak channels.

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