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1.
Entropy (Basel) ; 25(3)2023 Mar 04.
Artigo em Inglês | MEDLINE | ID: mdl-36981340

RESUMO

We present an analysis of the pseudorapidity η and transverse momentum pT distributions of charged hadrons in pp collisions for the kinematic range of 01 GeV/c at 0.9 and 2.36 TeV within the experimental errors, while Dire overshoots and Vicia undershoots the data by 50% each. At 7 TeV, the Dire module presents a good prediction, whereas the Simple and Vincia modules underestimate the data within 30% and 50%. Comparing the Simple module of the Pythia model and the predictions of the CRMC models with the experimental data shows that at 0.9 TeV, EPOS-LHC has better results than the others. At 2.36 GeV, the cosmic rays Monte Carlo (CRMC) models have better prediction than the Simple module of Pythia at low pT, while QGSJETII-04 predicts well at high pT. QGSJETII-04 and EPOS-LHC have closer results than the Pythia-Simple and Sibyll2.3d at 7 TeV. In the case of the pseudorapidity distributions, only the Pythia-Simple reproduced the experimental measurements at all energies. The Dire module overestimates, while Vincia underestimates the data in decreasing order of discrepancy (20%, 12%, 5%) with energy. All CRMC models underestimate the data over the entire η range at all energies by 20%. The angular ordering of partons and the parton fragmentation could be possible reasons for this deviation. Furthermore, we used the two-component standard distribution to fit the pT spectra to the experimental data and extracted the effective temperature (Teff) and the multiplicity parameter (N0). It is observed that Teff increases with the increase in the center of mass energy. The fit yielded 0.20368±0.01, 0.22348±0.011, and 0.24128±0.012 GeV for 0.9, 2.36, and 7 TeV, respectively. This shows that the system at higher energies freezes out earlier than lower ones because they quickly attain the equilibrium state.

2.
Angew Chem Int Ed Engl ; 62(5): e202213932, 2023 Jan 26.
Artigo em Inglês | MEDLINE | ID: mdl-36353929

RESUMO

Ion migration is a notorious phenomenon observed in ionic perovskite materials. It causes several severe issues in perovskite optoelectronic devices such as instability, current hysteresis, and phase segregation. Here, we report that, in contrast to lead halide perovskites (LHPs), no ion migration or phase segregation was observed in tin halide perovskites (THPs) under illumination or an electric field. The origin is attributed to a much stronger Sn-halide bond and higher ion migration activation energy (Ea ) in THPs, which remain nearly constant under illumination. We further figured out the threshold Ea for the absence of ion migration to be around 0.65 eV using the CsSny Pb1-y (I0.6 Br0.4 )3 system whose Ea varies with Sn ratios. Our work shows that ion migration does not necessarily exist in all perovskites and suggests metallic doping to be a promising way of stopping ion migration and improving the intrinsic stability of perovskites.

3.
Pak J Pharm Sci ; 36(2): 373-378, 2023 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-37530143

RESUMO

Hyperglycemia is a long-lasting syndrome that occurs either when the pancreas cannot produce enough insulin, or the body cannot effectively utilize that insulin to regulate blood sugar levels. Non-insulin-dependent hyperglycemia, also known as type II diabetes, causes a common consequence of severe damage to many of the body's organs mainly the blood vessels and nerves. The majority of people around the world are suffering from non-insulin-dependent diabetes. The present work showed a great effort to investigate any possible interaction between antacids and sitagliptin (anti-diabetic drug) in the treatment of type II diabetes with gastrointestinal tract problems. The in vitro studies were carried out in simulated gastric juice pH 2.0 and intestinal pH 7.4 at 37oC. MgCO3, NaHCO3, Mg(OH)2, Al(OH)3 and CaCO3 were used as antacids in these studies. It has been observed that % release of sitagliptin was significantly enhanced in the presence of calcium carbonate and magnesium carbonates.


Assuntos
Diabetes Mellitus Tipo 2 , Hiperglicemia , Humanos , Antiácidos/uso terapêutico , Fosfato de Sitagliptina/uso terapêutico , Diabetes Mellitus Tipo 2/tratamento farmacológico , Carbonato de Cálcio/uso terapêutico , Hiperglicemia/tratamento farmacológico
4.
Qatar Med J ; 2023(4): 27, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37936885

RESUMO

INTRODUCTION: Pets and exotic animals are increasingly popular all over the world. Some of these animals may cause injuries to their owners or other people during interactions. Both injuries and systemic infections always present diagnosis and treatment challenges. Emergency physicians´ clinical experience in managing patients with injuries caused by pets and exotic animals, in particular, is limited; hence, we believe that it is a domain to explore in a Middle Eastern country to help raise awareness and provide reminders as to the best evidence-based medical practice. METHODS: Hamad Medical Corporation's hospital records of patients treated between 2015 and 2022 were analyzed retrospectively. Cases whose diagnosis was recorded as injuries caused by animals kept as pets were included in the study. Patients were evaluated in terms of demographic characteristics, type of injury, injury locations, injury severity, treatments applied, and complications. Descriptive statistics were carried out, and findings were expressed as percentages in a frequency table. RESULTS: Following a search of the electronic patient records during the period of interest, 43 patients were found to have sought treatment following an injury caused by a pet or domestic exotic animal. The mean age of the patients was 23.5 years; about three-quarters were male, and approximately half were children. All injuries were minor, and 74.4% were skin abrasions. The most commonly injured body parts were the hand, the leg, and facial injuries. It was observed that cats caused 53.5% of the injuries, whereas falcons were involved in 11.6% of the cases. All patients were prescribed prophylactic antibiotics, and 60.5% were administered a tetanus injection. CONCLUSION: Despite our study spanning over seven years, a relatively low number of patients reported to the government hospitals´ emergency departments. The injuries are most commonly caused by cats and often involve children and animal bites to hands. The key recommendations are for parents or childminders to always supervise children when interacting with animals, be particularly cautious, and wear some form of protection when handling pets and domestic, exotic animals. Whether it is a bite or a scratch, healthcare professionals should always anticipate the potential risk of infection, treat the patient accordingly, and prescribe prophylactic antibiotics.

5.
Pak J Pharm Sci ; 35(6(Special)): 1691-1698, 2022 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-36861230

RESUMO

Isolation of sodium and potassium salt of kolavenic acid (1,2), as a mixture of (3:1) and sodium and potassium salt of 16 oxo-cleroda-3,13(14) E-dien-15-oic acid (3, 4) as a mixture of (1:1) are first time reported form reddish black ripe and green unripe berries of Polyalthia longifolia var. pendula respectively. Three known constituents obtained, were identified as cleroda-3, 13(14) E-dien-15-oic acid (kolavenic acid) (5), 16(R and S)-hydroxy cleroda-3,13 (14)Z-dien-15,16-olide (6) and 16 oxo-cleroda-3,13(14) E-dien-15-oic acid (7). Structures of all these compounds have been determined through spectral studies while metal analyses were carried out to confirm the structure of the salts. Compounds 3, 4 and 7 possess cytotoxic activity against lung (NCI-H460), oral (CAL-27) and normal mouse fibroblast (NCI-3T3) cancer cell lines. Diterpenoid (7), a bioprivileged, compound shows potent cytotoxic activity against oral cancer cell line (CAL-27) with IC50 11.3±0.6µg/mL in comparison with the standard 5-flourouracil (IC50 12.7±0.1µg/mL) and lungs cancer cell lines (NCI-H460) with IC50 5.3±0.2µg/mL as compared to the standard drug cisplatin (IC50 5.7±0.2µg/mL).


Assuntos
Annonaceae , Antineoplásicos , Diterpenos Clerodânicos , Plantas Medicinais , Polyalthia , Animais , Camundongos , Diterpenos Clerodânicos/farmacologia , Sais , Antineoplásicos/farmacologia , Potássio
6.
Psychooncology ; 30(6): 882-891, 2021 06.
Artigo em Inglês | MEDLINE | ID: mdl-33609048

RESUMO

OBJECTIVES: This study assessed resilience in brain tumor patients at a tertiary care hospital in Pakistan (a lower middle-income country; LMIC) and explored its relationship with patients' sociodemographic factors, clinical characteristics, social support, and mental health. METHODS: A cross-sectional survey was conducted amongst adult (≥18 years) patients with brain tumor at the Aga Khan University Hospital, Pakistan. Resilience was assessed by Wagnild and Young's Resilience Scale, and patients' psychosocial characteristics by the Hospital Anxiety and Depression Scale and the Enriched Social Support Instrument. RESULTS: A total of 250 patients were included (mean age: 44 years; 68% males), with majority (97.6%) having high social support and only 4.4% and 2% having symptomatic depression and anxiety, respectively. On multivariable linear regression adjusted for covariates, lower resilience was associated with not being involved in household decision-making (Adjusted Beta Coefficient: 4.58 [95% Confidence Interval:-7.59, -1.56]), not currently working (-2.80 [-4.61, -0.99]), undergoing multiple neurosurgical interventions such as tumor biopsies or resections (-8.64 [-13.11, -4.16]), receiving chemotherapy (-5.17 [-9.51, -0.83]) or combination adjuvant therapy (-2.91 [-5.14, -0.67]), low social support (-7.77 [-13.73, 1.81]), mild depression (-13.00 [-17.00,-8.99]) or symptomatic depression (-19.79 [-24.69, -14.89]), and mild anxiety (-4.24 [-7.98, -0.50]). CONCLUSION: Our study highlights the function of familial/household role and working status in mediating resilience, and demonstrates the well-known protective effect of resilience for mental health in brain tumor patients in Pakistan, a South-Asian LMIC. These findings are of clinical relevance with regards to the development of culture-specific evidence-based resilience-building interventions that may help patients with brain tumors to cope with the psychological distress of cancer.


Assuntos
Neoplasias Encefálicas , Resiliência Psicológica , Adulto , Ansiedade/epidemiologia , Estudos Transversais , Depressão/epidemiologia , Feminino , Humanos , Masculino , Paquistão
7.
Sensors (Basel) ; 21(4)2021 Feb 06.
Artigo em Inglês | MEDLINE | ID: mdl-33561989

RESUMO

Convolutional neural networks (CNN) are relational with grid-structures and spatial dependencies for two-dimensional images to exploit location adjacencies, color values, and hidden patterns. Convolutional neural networks use sparse connections at high-level sensitivity with layered connection complying indiscriminative disciplines with local spatial mapping footprints. This fact varies with architectural dependencies, insight inputs, number and types of layers and its fusion with derived signatures. This research focuses this gap by incorporating GoogLeNet, VGG-19, and ResNet-50 architectures with maximum response based Eigenvalues textured and convolutional Laplacian scaled object features with mapped colored channels to obtain the highest image retrieval rates over millions of images from versatile semantic groups and benchmarks. Time and computation efficient formulation of the presented model is a step forward in deep learning fusion and smart signature capsulation for innovative descriptor creation. Remarkable results on challenging benchmarks are presented with a thorough contextualization to provide insight CNN effects with anchor bindings. The presented method is tested on well-known datasets including ALOT (250), Corel-1000, Cifar-10, Corel-10000, Cifar-100, Oxford Buildings, FTVL Tropical Fruits, 17-Flowers, Fashion (15), Caltech-256, and reported outstanding performance. The presented work is compared with state-of-the-art methods and experimented over tiny, large, complex, overlay, texture, color, object, shape, mimicked, plain and occupied background, multiple objected foreground images, and marked significant accuracies.

8.
Transfusion ; 60 Suppl 6: S86-S100, 2020 10.
Artigo em Inglês | MEDLINE | ID: mdl-33089937

RESUMO

The quantification of the coagulopathic state associated with oncologic and hematologic diseases is imperfectly assessed by common coagulation tests such as prothrombin time, activated partial thromboplastin time, fibrinogen levels, and platelet count. These tests provide a static representation of a component of hemostatic integrity, presenting an incomplete picture of coagulation in these patients. Viscoelastic tests (VETs), such as rotational thromboelastometry (ROTEM) and thromboelastography (TEG), as whole blood analyses, provide data related to the cumulative effects of blood components and all stages of the coagulation and fibrinolytic processes. The utility of VETs has been demonstrated since the late 1960s in guiding blood component therapy for patients undergoing liver transplantation. Since then, the scope of viscoelastic testing has expanded to become routinely used for cardiac surgery, obstetrics, and trauma. In the past decade, VETs' expanded usage has been most significant in trauma resuscitation. However, use of VETs for patients with malignancy-associated coagulopathy (MAC) and hematologic malignancies is increasing. For the purposes of this narrative review, we discuss the similarities between trauma-induced coagulopathy (TIC) and MAC. These similarities center on the thrombomodulin-thrombin complex as it switches between the thrombin-activatable fibrinolysis inhibitor coagulation pathway and activating the protein C anticoagulation pathway. This produces a spectrum of coagulopathy and fibrinolytic alterations ranging from shutdown to hyperfibrinolysis that are common to TIC, MAC, and hematologic malignancies. There is expanding literature regarding the utility of TEG and ROTEM to describe the hemostatic integrity of patients with oncologic and hematologic conditions, which we review here.


Assuntos
Transtornos da Coagulação Sanguínea/sangue , Fibrinólise , Neoplasias/sangue , Tromboelastografia/métodos , Antineoplásicos/efeitos adversos , Coagulação Sanguínea/fisiologia , Transtornos da Coagulação Sanguínea/diagnóstico , Transtornos da Coagulação Sanguínea/etiologia , Medicina Baseada em Evidências , Doenças Hematológicas/sangue , Neoplasias Hematológicas/sangue , Humanos , Neoplasias/complicações , Policitemia Vera/sangue , Tromboelastografia/instrumentação , Trombocitopenia/sangue , Trombocitopenia/induzido quimicamente , Ferimentos e Lesões/sangue , Ferimentos e Lesões/complicações
9.
Pak J Med Sci ; 36(7): 1596-1600, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-33235581

RESUMO

OBJECTIVE: To assess the episodes of pneumonia and diarrhea in vaccinated and unvaccinated children under 60 months of age. METHODS: This descriptive cross-sectional study was carried out at Darul Sehat Hospital and SESSI, Karachi in the Department of Pediatrics from 1st November 2018 to 3rd February 2019. An interview based questionnaire was administered and selection of participants was done by convenience sampling. Total of 196 participants were selected for interview. RESULTS: Total 196 participants were interviewed which included mothers of children between the age group of 1- 60 months. The questions were entered on the questionnaire after taking consent from the mothers. Among them, males were 98 (52.7%) and females were 88(47.3%). One hundred seventy two (88.7%) children were vaccinated for pneumococcal and rotavirus whereas unvaccinated children were 22(11.3%). There was an incidence of 66(63.5%) for loose watery diarrhea. In vaccinated children, grading of diarrhea was found to be severe cases as 30 (34.9%), moderate cases as 27 (31.4%) and mild cases as 29(33.7%). For unvaccinated children, severe cases were 12 (66.7%) and for mild and moderate cases were (11.1%) and 04(22.2%) respectively with p value of 0.035. As compared to their unvaccinated counterparts, the frequency of severe pneumonia was far less than cough and cold in vaccinated children (p<0.001). CONCLUSION: There is significant reduction in cases of severe pneumonia in children receiving pneumococcal vaccine as compared to children receiving Rota vaccine there is moderate reduction in cases of severe diarrhea. The overall coverage of Pneumococcal and Rota vaccines was higher in our sample population. Efforts should be made to increase the awareness of Rotavirus vaccination in order to have better coverage in future.

10.
J Pak Med Assoc ; 69(4): 474-477, 2019 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-31000847

RESUMO

OBJECTIVE: To observe and describe the features of line a aspera in dry femurs. METHODS: The prospective observational study was conducted from October to December 2017 at Darul Sehat Hospital, Karachi, and comprised dry femurs. Data was collected by trained medical students. Observations of landmarks of linea aspera were taken using classical measuring techniques. Data was analysed using SPSS 21. RESULTS: There were 48 dry femurs with mean maximum length of linea aspera 133.4±22.4 mm, and mean minimum length 188±79 mm. The mean diameter of antero posterior thickness was 2.7±1.1 mm. Linea aspera was widest at its lower one third 30(62.5%) and narrowest at its middle one-third 5 (10.4%). The most common pattern on linea aspera was three ridges 26 (54.2%). Majority of bones had at least one uninterrupted ridge 32(66.7%). The most prominent ridge on linea aspera was lateral in 20 (41.7%) bones. The largest nutrient foramen in 19 (42.2%) bones was located at the level of proximal one-third of linea aspera.. CONCLUSIONS: linea aspera was widest at its lower one-third. In majority of bones the lateral ridge was the most prominent, and the largest nutrient foramen of femur was most commonly located at the level of proximal one-third of linea aspera.


Assuntos
Fêmur/anatomia & histologia , Ósteon , Humanos , Tamanho do Órgão
11.
J Pak Med Assoc ; 69(10): 1547-1549, 2019 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-31622314

RESUMO

Sjogren's syndrome most commonly presents with dry eyes, dry mouth, joint pain and fatigue. However, recurrent aseptic meningitis, reported as the most uncommon initial symptom, was the presenting feature in our case. We present the case of a 19-year-old female with recurrent episodes of aseptic meningitis. She presented with fever, headache, vomiting and photophobia. Neurological examination showed neck stiffness. Fundoscopy was normal. On two previous occasions her cerebrospinal fluid analysis was consistent with meningitis; however, it was normal at this presentation. Review of system revealed history of fatigue and sicca symptoms since early childhood. Autoimmune workup showed antinuclear antibodies with a titer of 1:400 and positive anti SSA (Ro) antibodies that led to the diagnosis of Sjogren's syndrome. She responded well to intravenous steroids, followed by oral prednisolone and hydroxychloroquine. To conclude, diagnosis of Sjogren's syndrome may also be considered in a patient presenting with recurrent aseptic meningitis.


Assuntos
Meningite Asséptica/etiologia , Síndrome de Sjogren/complicações , Anticorpos Antinucleares/imunologia , Antirreumáticos/uso terapêutico , Fadiga/etiologia , Feminino , Glucocorticoides/uso terapêutico , Humanos , Hidroxicloroquina/uso terapêutico , Meningite Asséptica/líquido cefalorraquidiano , Prednisolona/uso terapêutico , Recidiva , Síndrome de Sjogren/diagnóstico , Síndrome de Sjogren/tratamento farmacológico , Síndrome de Sjogren/imunologia , Adulto Jovem
12.
Pak J Med Sci ; 35(1): 241-246, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-30881431

RESUMO

BACKGROUND & OBJECTIVES: Neonatal septicemia is responsible for 1.5 to 2.0 million deaths/year in the under developed countries of the world. Pakistan is number three among these countries and accounts for 7% of global neonatal deaths. The objective of the study was to determine the role of simple hematological parameter, immature to total neutrophil ratio (I/T ratio) in diagnosing early onset neonatal bacterial infection. METHODS: A descriptive cross-sectional study was conducted in Neonatal Intensive Care Unit of Liaquat College of Medicine & Dentistry (LCMD) Hospital from January 2016 to January 2017. A total 85 neonates were admitted with clinical suspicion of presumed early onset sepsis or who had potential risk factors for sepsis like prematurity, prolonged rupture of membranes was carried out. After taking informed consent from parents of admitted neonates, data was collected in a structured questionnaire. Laboratory workup included White blood cell count, CRP, absolute neutrophil count, immature neutrophil count while blood C/S was kept as gold standard. Empirical antibiotics started after sample collection for workup. Manual differential count and immature neutrophil count of the peripheral blood smear was performed by a senior technician masked to clinical information. I/T ratio was calculated from WBC, neutrophils and immature neutrophil count by a simple formula. RESULTS: Out of 85 neonates, 13 had positive blood cultures (15.29%). The mean white blood count was 18761.18 ± 8570.75 and mean I/T ratio was 0.1622 ± 0.0419. About 50% of proven sepsis cases had WBC higher than 26000 as compared to 50% of cases for negative diagnoses that had WBC <15500. The mean I/T in positive CRP 0.204 ± 0.04 was non-significantly higher as compared to negative CRP 0.151 ± 0.034 (p =0.084). Point biserial correlation revealed that I/T ratio was significant strong correlation (rpb = 0.721, p < 0.001) and overall I/T ratio was a good indicator of a positive and negative blood culture result. The sensitivity, specificity, positive predictive value (PPV) and negative predictive value (NPV) of I/T ratio were 76.47%, 83.82%, 54.16% and 93.44% respectively. Similarly majority of neonates having high I/T ratio also depicts positive C-reactive protein (CRP) (NPV 91.23%). Therefore, both I/T and CRP showed a high negative predictive value (I/T = 93.44% and CRP = 91.23%) in this study. CONCLUSION: I/T ratio is a useful tool for early onset sepsis (EOS) with reasonable specificity but cannot be relied upon as sole indicator. Combination of normal immature to total neutrophil Ratio with negative CRP values in neonates with presumed sepsis is an indicator of non-infected neonate which comprised 78.8% of our study population.

13.
Pak J Med Sci ; 35(3): 731-736, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31258585

RESUMO

OBJECTIVE: To determine the role of montelukast - a leukotriene receptor antagonist (LTRA) - in improving the quality of life (QOL) and asthma control of adult patients with mild to moderate persistent asthma. METHODS: Randomized, double-blind, placebo-controlled, non-crossover trial was conducted from March 2017 till November 2018 in three hospitals of Karachi and Hyderabad. Adults of age 15 years or more with mild to moderate persistent asthma. Treatment group was administered tablet montelukast 10mg once daily; the other group was given a similar looking placebo; as an adjuvant to the current medication. QOL was assessed with Asthma Quality of Life Questionnaire - Standard (AQLQ-S) before and after the treatment. Asthma control was monitored via Asthma Control Test (ACT). RESULTS: After 4 weeks, the mean ± SD of overall QOL on AQLQ-S improved from 3.74±0.88 to 5.06±0.89 for montelukast group and from 3.58±0.92 to 4.71±0.97 for placebo group (p=0.02). The improvement in sub-domains of symptoms, activity, and emotional functions was not significant; however, the sub-domain "environmental stimuli" significantly improved with 5.06±0.89 for montelukast group and 4.71±0.97 for placebo group (p=0.02). The mean ± SD of ACT, after four weeks, for montelukast group was 18.19±2.91 and for placebo group 17.28±3.36. Only on ACT, Montelukast did not show any statistically insignificant results. CONCLUSION: The role of montelukast in improving QOL of adult patients with mild to moderate persistent asthma is quite beneficial. It improves patient quality of life. It has the ease of once daily oral administration and also eradicates side effects associated with long-term adherence to steroids.

14.
Pak J Med Sci ; 35(3): 797-801, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31258597

RESUMO

OBJECTIVE: To determine frequency of electrolyte imbalance including sodium, chloride, potassium and magnesium levels present in patients with uncontrolled diabetes at a tertiary care hospital in Karachi. METHODS: This was a descriptive cross sectional study conducted at Medicine Department, Darul Sehat Hospital, Karachi, Pakistan from March 2017 to October 2017. A total of one hundred and eighty one admitted and OPD patients with uncontrolled diabetes (HbA1c more than 7%) were included and their demographics, comorbidities, microvascular complications, drug history, fasting and random blood glucose and serum electrolyte levels were recorded. RESULTS: In uncontrolled diabetes mellitus, decrease in serum sodium and chloride levels were observed to be statistically highly significant (p-value less than or equal to 0.05) while that of potassium and magnesium showed insignificant alterations. Sodium level was also observed to decline with increasing pattern of urine for microalbumin. CONCLUSION: Electrolyte imbalance is markedly present in patients with uncontrolled blood sugars therefore serum electrolytes should be routinely measured in patients with type 2 diabetes mellitus. Serum fasting blood glucose can be used as a predictor for electrolytes.

15.
Nanotechnology ; 29(11): 115701, 2018 Mar 16.
Artigo em Inglês | MEDLINE | ID: mdl-29313820

RESUMO

Two dimensional (2D) single crystal layered transition materials have had extensive consideration owing to their interesting magnetic properties, originating from their lattices and strong spin-orbit coupling, which make them of vital importance for spintronic applications. Herein, we present synthesis of a highly crystalline tungsten diselenide layered single crystal grown by chemical vapor transport technique and doped with nickel (Ni) to tailor its magnetic properties. The pristine WSe2 single crystal and Ni-doped crystal were characterized and analyzed for magnetic properties using both experimental and computational aspects. It was found that the magnetic behavior of the 2D layered WSe2 crystal changed from diamagnetic to ferromagnetic after Ni-doping at all tested temperatures. Moreover, first principle density functional theory (DFT) calculations further confirmed the origin of room temperature ferromagnetism of Ni-doped WSe2, where the d-orbitals of the doped Ni atom promoted the spin moment and thus largely contributed to the magnetism change in the 2D layered material.

16.
Langmuir ; 33(21): 5148-5153, 2017 05 30.
Artigo em Inglês | MEDLINE | ID: mdl-28489390

RESUMO

We demonstrate a heterostructure Ni9S8/MoS2 hybrid with tight interface synthesized via an improved hydrothermal method. As compared to pure MoS2, the increased surface area and the shorten charge transport pathway in the layered hybrid significantly promote the photocatalytic efficiency for hydrogen evolution reaction (HER). In particularly, the optimized Ni9S8/MoS2 hybrid with 20 wt % Ni9S8 exhibits the highest photocatalytic activity with HER value of 406 µmolg-1h-1, which is enhanced by 70% compared to that of pure MoS2 nanosheets (285.0 µmolg-1h-1). Moreover, the value is 4 times more than the commercial MoS2 (92.0 µmolg-1h-1), indicating the high potential of the hybrid in the catalytic fields.

17.
Phys Chem Chem Phys ; 19(3): 1735-1739, 2017 Jan 18.
Artigo em Inglês | MEDLINE | ID: mdl-28009864

RESUMO

A room-temperature ferromagnetic behavior was observed in a ternary layered-Cu2MoS4 nanosheet. Both the coercivity and magnetization saturation increased with a decrease in temperature. The electron paramagnetic resonance spectroscopy confirmed a high g value. Combined with atomic structural observations, our first principle calculations revealed that the ferromagnetism originated from the edged molybdenum atoms.

19.
Haematologica ; 100(9): 1214-21, 2015 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-26022710

RESUMO

Multiple myeloma is preceded by an asymptomatic phase, comprising monoclonal gammopathy of uncertain significance and smoldering myeloma. Compared to the former, smoldering myeloma has a higher and non-uniform rate of progression to clinical myeloma, reflecting a subset of patients with higher risk. We evaluated the gene expression profile of smoldering myeloma plasma cells among 105 patients enrolled in a prospective observational trial at our institution, with a view to identifying a high-risk signature. Baseline clinical, bone marrow, cytogenetic and radiologic data were evaluated for their potential to predict time to therapy for symptomatic myeloma. A gene signature derived from four genes, at an optimal binary cut-point of 9.28, identified 14 patients (13%) with a 2-year therapy risk of 85.7%. Conversely, a low four-gene score (< 9.28) combined with baseline monoclonal protein < 3 g/dL and albumin ≥ 3.5 g/dL identified 61 patients with low-risk smoldering myeloma with a 5.0% chance of progression at 2 years. The top 40 probe sets showed concordance with indices of chromosome instability. These data demonstrate high discriminatory power of a gene-based assay and suggest a role for dysregulation of mitotic checkpoints in the context of genomic instability as a hallmark of high-risk smoldering myeloma.


Assuntos
Genes Neoplásicos , Instabilidade Genômica , Mieloma Múltiplo/genética , Proteínas de Neoplasias/genética , Idoso , Idoso de 80 Anos ou mais , Medula Óssea/patologia , Feminino , Humanos , Masculino , Mieloma Múltiplo/patologia , Estudos Prospectivos
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