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1.
Spectrochim Acta A Mol Biomol Spectrosc ; 312: 124065, 2024 May 05.
Artigo em Inglês | MEDLINE | ID: mdl-38402703

RESUMO

Carbon quantum dots (CQDs)-based composites as luminous down-conversion materials are becoming more popular due to several advantages such as steady fluorescence, ease of functionalization, tailoring of emission in the visible range, and so on. We report an inexpensive and environmentally sustainable synthesis of fluorescent nitrogen doped-CQDs produced from Cissus quadrangularis, a low-cost plant precursor with therapeutic value. The morphological, structural, and physicochemical features of the material were carefully investigated. Under UV stimulation (365 nm), almost spherical shaped N-CQDs with an average diameter of 5.1 nm were discovered to generate yellow-green fluorescence, have excellent photostability, and strong water solubility, with a quantum yield of up to 5 %. Furthermore, as a solid-phase dispersion matrix for CQDs, ecologically friendly and biodegradable bioplastic is appealing. The down-conversion of solid-state fluorescence of LEDs and UVC tubes was demonstrated by creating a nanocomposite by inserting N-CQDs into the solid matrix of a wheat starch-based bioplastic. Furthermore, employing constructed quantum dot-based optical displays, down-converted LEDs, and UVC tubes, the impacts of varied CQD concentrations and pH sensitivity were examined.

2.
Phys Rev Lett ; 116(24): 240405, 2016 Jun 17.
Artigo em Inglês | MEDLINE | ID: mdl-27367369

RESUMO

Understanding the resource consumption in distributed scenarios is one of the main goals of quantum information theory. A prominent example for such a scenario is the task of quantum state merging, where two parties aim to merge their tripartite quantum state parts. In standard quantum state merging, entanglement is considered to be an expensive resource, while local quantum operations can be performed at no additional cost. However, recent developments show that some local operations could be more expensive than others: it is reasonable to distinguish between local incoherent operations and local operations which can create coherence. This idea leads us to the task of incoherent quantum state merging, where one of the parties has free access to local incoherent operations only. In this case the resources of the process are quantified by pairs of entanglement and coherence. Here, we develop tools for studying this process and apply them to several relevant scenarios. While quantum state merging can lead to a gain of entanglement, our results imply that no merging procedure can gain entanglement and coherence at the same time. We also provide a general lower bound on the entanglement-coherence sum and show that the bound is tight for all pure states. Our results also lead to an incoherent version of Schumacher compression: in this case the compression rate is equal to the von Neumann entropy of the diagonal elements of the corresponding quantum state.

3.
Sci Rep ; 6: 26555, 2016 05 25.
Artigo em Inglês | MEDLINE | ID: mdl-27222033

RESUMO

The antiquity and decline of the Bronze Age Harappan civilization in the Indus-Ghaggar-Hakra river valleys is an enigma in archaeology. Weakening of the monsoon after ~5 ka BP (and droughts throughout the Asia) is a strong contender for the Harappan collapse, although controversy exists about the synchroneity of climate change and collapse of civilization. One reason for this controversy is lack of a continuous record of cultural levels and palaeomonsoon change in close proximity. We report a high resolution oxygen isotope (δ(18)O) record of animal teeth-bone phosphates from an archaeological trench itself at Bhirrana, NW India, preserving all cultural levels of this civilization. Bhirrana was part of a high concentration of settlements along the dried up mythical Vedic river valley 'Saraswati', an extension of Ghaggar river in the Thar desert. Isotope and archaeological data suggest that the pre-Harappans started inhabiting this area along the mighty Ghaggar-Hakra rivers fed by intensified monsoon from 9 to 7 ka BP. The monsoon monotonically declined after 7 ka yet the settlements continued to survive from early to mature Harappan time. Our study suggests that other cause like change in subsistence strategy by shifting crop patterns rather than climate change was responsible for Harappan collapse.

4.
Phys Rev Lett ; 116(7): 070402, 2016 Feb 19.
Artigo em Inglês | MEDLINE | ID: mdl-26943512

RESUMO

We introduce and study the task of assisted coherence distillation. This task arises naturally in bipartite systems where both parties work together to generate the maximal possible coherence on one of the subsystems. Only incoherent operations are allowed on the target system, while general local quantum operations are permitted on the other; this is an operational paradigm that we call local quantum-incoherent operations and classical communication. We show that the asymptotic rate of assisted coherence distillation for pure states is equal to the coherence of assistance, an analog of the entanglement of assistance, whose properties we characterize. Our findings imply a novel interpretation of the von Neumann entropy: it quantifies the maximum amount of extra quantum coherence a system can gain when receiving assistance from a collaborative party. Our results are generalized to coherence localization in a multipartite setting and possible applications are discussed.

5.
Saudi J Kidney Dis Transpl ; 26(5): 996-9, 2015 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-26354577

RESUMO

Primary synovial sarcoma (SS) of the kidney is a very rare disease as well as a diagnostic dilemma. Here, we present a case of a 60-year-old male clinically diagnosed as renal cell carcinoma. The radical nephrectomy specimen showed a well-circumscribed renal mass of approximately 13 cm × 9 cm × 7 cm. The cut-surface of the mass was tawny and firm, with cystic areas, and also showed focal hemorrhage and necrosis. Histologically, the tumor was composed of spindle cells arranged in the intersecting fascicles, alternating with hypocellular areas suggestive of monophasic synovial sarcoma. Morphological and immunohistochemical features were compatible with the diagnosis of SS of the kidney.


Assuntos
Carcinoma de Células Renais/patologia , Neoplasias Renais/patologia , Sarcoma Sinovial/patologia , Biomarcadores Tumorais/química , Biomarcadores Tumorais/genética , Biópsia , Carcinoma de Células Renais/química , Carcinoma de Células Renais/genética , Erros de Diagnóstico , Humanos , Neoplasias Renais/química , Neoplasias Renais/genética , Neoplasias Renais/cirurgia , Imageamento por Ressonância Magnética , Masculino , Pessoa de Meia-Idade , Nefrectomia , Valor Preditivo dos Testes , Sarcoma Sinovial/química , Sarcoma Sinovial/genética , Sarcoma Sinovial/cirurgia , Carga Tumoral
6.
Sci Rep ; 5: 8497, 2015 Feb 17.
Artigo em Inglês | MEDLINE | ID: mdl-25687953

RESUMO

We report on the counter intuitive reversible crystallisation of two-dimensional monolayer of Trisilanolisobutyl Polyhedral Oligomeric SilSesquioxane (TBPOSS) on water surface using synchrotron x-ray scattering measurements. Amphiphilic TBPOSS form rugged monolayers and Grazing Incidence X-ray Scattering (GIXS) measurements reveal that the in-plane inter-particle correlation peaks, characteristic of two-dimensional system, observed before transition is replaced by intense localized spots after transition. The measured x-ray scattering data of the non-equilibrium crystalline phase on the air-water interface could be explained with a model that assumes periodic stacking of the TBPOSS dimers. These crystalline stacking relaxes upon decompression and the TBPOSS layer retains its initial monolayer state. The existence of these crystals in compressed phase is confirmed by atomic force microscopy measurements by lifting the materials on a solid substrate.

7.
J Nanosci Nanotechnol ; 14(5): 3538-44, 2014 May.
Artigo em Inglês | MEDLINE | ID: mdl-24734584

RESUMO

Resistive switching behavior of Au nanodot-embedded Nb2O5 memristor devices is reported. Due to controlled formation and/or rupture of conductive filaments; Au nanodot-embedded Nb2O5 devices show better consistency during transition from high to low resistance state and vice-versa. The memristive transition is explained using a physical model which involves oxygen ion, O(2-) trapping or detrapping at the metal-oxide interface, and O(2-) transport and annihilation with the oxygen vacancies in the breakdown percolation path. The experimental results indicate that Au nanodot-embedded Nb2O5 memristors may find applications as non-volatile memory devices.

8.
Indian J Tuberc ; 60(1): 15-22, 2013 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-23540084

RESUMO

BACKGROUND: Tuberculosis had been declared by the World Health Organization (WHO) as 'public health emergency' in 1993. Extra pulmonary tuberculosis (E.P.T.B.) comprises 20-25% total burden of the disease in which genitourinary tuberculosis (GU.T.B.) is 4%. Timely diagnosis and treatment will prevent the sequelae of this disease. AIMS: To know the varied clinical presentations, diagnostic modalities and management of G.U.T.B. METHODS: During a 13-year-period, 117 retrospective cases of GUTB were admitted in the tertiary care centre. They were analyzed for clinical presentation, diagnostic modalities and management. RESULTS: Young patients mainly in third decade of life were commonly affected with higher incidence in females. In our study, the most common presentation was irritative voiding symptoms (66.47%) followed by haematuria (47.60%). Although it can affect the entire organ in genito-urinary system but, in the present study, kidney was the most affected organ (64.9%) following ureter (27.35%), urinary bladder (17.09%), prostate (3.4%) and epididymis (5.19%). In this study, we had not encountered any case of testicular and penile tuberculosis. Among the different diagnostic modalities in this study, the diagnostic positivity rate was 41.6% for the urine AFB test, 55.4% for the urine M. tuberculosis culture test and 67.7% for PCR. Chest x-ray was positive in 25.6% (30). ESR was raised in 62.5% and Mantoux test was positive in 61.2% patients. CONCLUSION: A high index of suspicion and a wide range of investigations may be required to achieve a complete diagnosis of genitourinary tuberculosis. Though short course chemotherapy with four-drug-regimen for six-month-duration is the mainstay of treatment, surgical interventions were required in 60% of cases of this study.


Assuntos
Antituberculosos/uso terapêutico , Diagnóstico por Imagem/métodos , Técnicas de Diagnóstico Urológico , Previsões , Tuberculose Urogenital/epidemiologia , Feminino , Humanos , Incidência , Índia/epidemiologia , Masculino , Reprodutibilidade dos Testes , Estudos Retrospectivos , Distribuição por Sexo , Fatores Sexuais , Taxa de Sobrevida/tendências , Teste Tuberculínico , Tuberculose Urogenital/diagnóstico , Tuberculose Urogenital/tratamento farmacológico
10.
Saudi J Kidney Dis Transpl ; 22(6): 1169-74, 2011 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-22089776

RESUMO

Endoscopic incision is a good management option for orthotopic ureterocele. But most of the literature has shown its efficacy only in children. We have done this retrospective study to evaluate the safety and efficacy of endoscopic incision of orthotopic ureterocele in adults. From March 2004 to January 2008, at our center, 26 adults underwent transurethral, transverse incision of an ureterocele. The perioperative data of these patients were retrospectively analyzed. The literature was reviewed to identify all the reported options for management of this relatively rare condition in adults. Unilateral ureterocele was present in 24 patients and two patients had bilateral ureterocele. One patient had associated upper tract stones. Three patients had associated stones in ureterocele. Transurethral, transverse incision of ureterocele was given in all patients. The mean postoperative hospital stay was 50.5 h. Twenty-three patients were available for follow-up at three, six and 12 months. All patients were symptom free. At three months ultrasound and intravenous urography revealed no residual ureterocele but four patients showed residual hydronephrosis, but with a decrease in the grade indicating decompression. Micturating cystourethrography revealed vesico-ureteral reflux (VUR) in two patients and the reflux persisted in one patient even at 6 months. We conclude that in adults, management with endoscopic incision of orthotopic ureterocele is safe and effective. VUR may occur in a few cases.


Assuntos
Endoscopia , Ureterocele/cirurgia , Adulto , Descompressão Cirúrgica/métodos , Feminino , Humanos , Masculino , Complicações Pós-Operatórias/epidemiologia , Estudos Retrospectivos , Ultrassonografia , Ureterocele/diagnóstico por imagem , Procedimentos Cirúrgicos Urológicos , Refluxo Vesicoureteral/epidemiologia
11.
J Environ Qual ; 40(6): 1983-90, 2011.
Artigo em Inglês | MEDLINE | ID: mdl-22031582

RESUMO

17ß-estradiol and testosterone are naturally occurring steroids that co-occur in poultry litter. The effects of litter on sorption of these hormones to soil are not known. Sorption isotherms were developed for C-labeled testosterone and H-labeled estradiol in a Cecil sandy clay loam with and without poultry litter addition. The effect of applying the hormones alone (single-sorbate) or together (multisorbate) was also investigated. C-testosterone sorption in soil increased from 2 to 48 h and remained relatively constant thereafter. H-estradiol sorption in soil was relatively constant from 2 to 24 h and then decreased to 72 h. These differences may reflect transformation of the parent hormones to products with different solid-phase affinity. The maximum sorption coefficient () in soil for C-testosterone (20.2 mL g) was similar to that for H-estradiol (19.6 mL g) in single-sorbate experiments. When hormones were applied together, sorption of both hormones in soil decreased, but the C-testosterone (12.5 mL g) was nearly twice as large as the H-estradiol (7.4 mL g). We propose this resulted from competition between the hormones and their transformation products for sorption sites, with C-testosterone and its expected transformation product (androstenedione) being better competitors than H-estradiol and its expected transformation product (estrone). When poultry litter was mixed with soil, sorption increased for H-estradiol but decreased for C-testosterone. This may have been because poultry litter slowed the transformation of parent hormones. Our results show that poultry litter could have important effects on the mobility of estradiol and testosterone.


Assuntos
Galinhas , Estradiol/química , Pisos e Cobertura de Pisos , Abrigo para Animais , Solo/química , Testosterona/química , Animais , Poluentes do Solo/química
12.
Phys Rev E Stat Nonlin Soft Matter Phys ; 83(5 Pt 1): 051605, 2011 May.
Artigo em Inglês | MEDLINE | ID: mdl-21728545

RESUMO

Structural reordering in monolayers of gold nanoparticles during transfer from water surface to solid substrate has been studied by synchrotron x-ray scattering techniques. Grazing incidence diffraction (GID) and grazing incidence x-ray off-specular scattering (GIXOS) measurements were performed as a function of time to track the in-plane and out-of-plane structural reordering in the transferred monolayers. GID measurements show shift in the in-plane particle-particle correlation peak toward the lower in-plane momentum transfer value, signifying possible expansion of triangular lattice formed on the water surface. However, GIXOS data and supportive microscopy measurements clearly show compactification in the in-plane structure and associated out-of-plane movements. A model that assumes the possibility of a two-dimensional short-range structural reordering from triangular to square-like lattice as a function of time could explain all the data. The observed change in the electron densities of the nanoparticles before and after the structural reordering matches well with the expected change in the calculated electron densities of the nanoparticles arranged in triangular (pretransition) and square-like (post-transition) symmetry.

13.
Urology ; 78(4): 779-81, 2011 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-21459423

RESUMO

We report an unusual cause of right ureteral obstruction by a normal running right spermatic vein in a 55-year-old man. Laparoscopic resection of the right spermatic vein was done. To the best of our knowledge, only 1 such case has been previously reported.


Assuntos
Imageamento por Ressonância Magnética/métodos , Obstrução Ureteral/diagnóstico , Humanos , Laparoscopia/métodos , Masculino , Pessoa de Meia-Idade , Cordão Espermático/cirurgia , Resultado do Tratamento , Obstrução Ureteral/cirurgia , Urografia/métodos
14.
Congenit Heart Dis ; 5(5): 454-7, 2010.
Artigo em Inglês | MEDLINE | ID: mdl-21087432

RESUMO

Pentalogy of Cantrell is a rare congenital anomaly involving deficiency of the following structures: anterior diaphragm, supraumbilical abdominal wall, diaphragmatic pericardium, lower sternum, and associated congenital intracardiac abnormality. We describe a 3-month-old child with this syndrome having left ventricular diverticulum along with omphalocele who presented to us with a pulsating mass in the epigastrium. The defect was evaluated and defined by computed tomography scan. A team of pediatric, cardiac, and plastic surgeons successfully repaired the defects. This case report discusses the review of literature along with management options and concludes that there must be an emphasis on early repair of left ventricular diverticulum to prevent complications. Antenatal ultrasound can also detect the anomaly, and early postnatal diagnosis of the syndrome, followed by immediate surgical repair, can prevent lethal complications.


Assuntos
Anormalidades Múltiplas , Divertículo/congênito , Ventrículos do Coração/anormalidades , Hérnia Umbilical/complicações , Pentalogia de Cantrell/complicações , Abdome/cirurgia , Procedimentos Cirúrgicos Cardíacos , Divertículo/diagnóstico por imagem , Divertículo/cirurgia , Feminino , Ventrículos do Coração/diagnóstico por imagem , Ventrículos do Coração/cirurgia , Hérnia Umbilical/diagnóstico por imagem , Hérnia Umbilical/cirurgia , Humanos , Lactente , Pentalogia de Cantrell/diagnóstico por imagem , Pentalogia de Cantrell/cirurgia , Tomografia Computadorizada por Raios X , Resultado do Tratamento
15.
Transplant Proc ; 41(1): 173-6, 2009.
Artigo em Inglês | MEDLINE | ID: mdl-19249507

RESUMO

Ureteral obstruction following renal transplantation is not an uncommon complication. Open surgery has been the traditional approach. In recent years, retrograde endourologic techniques have been used to manage this complication with good results. In cases of failure of retrograde catheterization of the neomeatus, a percutaneous approach is employed. We present a new technique of pneumovesicoscopic ureterotomy in case of posttransplant ureteric stricture, with failure of retrograde catheterization. This simple, minimally invasive approach for these patients avoids transplant kidney puncture.


Assuntos
Transplante de Rim/efeitos adversos , Complicações Pós-Operatórias/cirurgia , Obstrução Ureteral/cirurgia , Adulto , Humanos , Testes de Função Renal , Masculino , Pessoa de Meia-Idade , Resultado do Tratamento , Obstrução Ureteral/etiologia , Obstrução Ureteral/patologia
16.
Vet Pathol ; 45(2): 259-63, 2008 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-18424844

RESUMO

We describe a disseminated biphasic neoplasm in a young Madagascar tree boa utilizing transmission electron and light microscopy. Discrete neoplastic cells identified within pulmonary capillaries and hepatic sinusoids represented the leukemic phase. Spindloid cells represented the sarcomatous phase, which comprised hepatic and fat body nodules. A zone of transition of the neoplastic cells, from discrete to spindloid, was noted along the periphery of the hepatic and fat body nodules. Ultrastructural examination elucidated similar nuclear features in the discrete and spindloid neoplastic cells and revealed collagen fibers within the spindloid neoplastic cells. These ultrastructural findings indicate that the discrete and spindloid cells represent a single neoplastic process with a subpopulation of cells exhibiting mesenchymal differentiation.


Assuntos
Boidae , Neoplasias/veterinária , Animais , Feminino , Histocitoquímica/veterinária , Microscopia Eletrônica de Transmissão/veterinária , Neoplasias/patologia
18.
J Minim Access Surg ; 4(3): 76-9, 2008 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-19547693

RESUMO

BACKGROUND: Ureteropelvic junction obstruction (UPJO) causes hydronephrosis and progressive renal impairment may ensue if left uncorrected. Open pyeloplasty remains the standard against which new technique must be compared. We compared laparoscopic (LP) and open pyeloplasty (OP) in a randomized prospective trial. MATERIALS AND METHODS: A prospective randomized study was done from January 2004 to January 2007 in which a total of 28 laparoscopic and 34 open pyeloplasty were done. All laparoscopic pyeloplasties were performed transperitoneally. Standard open Anderson Hynes pyeloplasty, spiral flap or VY plasty was done depending on anatomic consideration. Patients were followed with DTPA scan at three months and IVP at six months. Perioperative parameters including operative time, analgesic use, hospital stay, and complication and success rates were compared. RESULTS: Mean total operative time with stent placement in LP group was 244.2 min (188-300 min) compared to 122 min (100-140 min) in OP group. Compared to OP group, the post operative diclofenac requirement was significantly less in LP group (mean 107.14 mg) and OP group required mean of (682.35 mg). The duration of analgesic requirement was also significantly less in LP group. The postoperative hospital stay in LP was mean 3.14 Days (2-7 days) significantly less than the open group mean of 8.29 days (7-11 days). CONCLUSION: LP has a minimal level of morbidity and short hospital stay compared to open approach. Although, laparoscopic pyeloplasty has the disadvantages of longer operative time and requires significant skill of intracorporeal knotting but it is here to stay and represents an emerging standard of care.

19.
Indian J Exp Biol ; 29(6): 538-42, 1991 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-1889827

RESUMO

N-phthaloyl GABA (P-GABA), a nonselective GABA-ergic drug, showed positive analgesic response in four different models in mice, viz-tail immersion, tail clip, hot plate and writhing-induced by acetic acid. Antinociceptive ED50 (ip in mice) of P-GABA was lowest in tail immersion method (ED50 = 24.27, mg/kg). Though pethidine (10 mg/kg, ip) significantly potentiated the antinociceptive action of P-GABA (20 mg/kg, ip), pretreatment of naloxone (5 mg/kg, im) did not influence the same. Pretreatment with atropine (10 mg/kg, im), picrotoxin (0.08 mg/kg) and 3-mercaptopropionic acid (2 mg/kg) reduced the antinociceptive action of P-GABA significantly. But pretreatment with bicuculline (0.4 mg/kg), a specific GABA antagonist, did not reduce the antinociceptive action of P-GABA.


Assuntos
Analgésicos , Ácido gama-Aminobutírico/análogos & derivados , Animais , Masculino , Camundongos , Ácido gama-Aminobutírico/farmacologia
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