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1.
Materials (Basel) ; 16(19)2023 Sep 26.
Article in English | MEDLINE | ID: mdl-37834554

ABSTRACT

Nowadays, nanotechnology offers opportunities to create new features and functions of emerging materials. Correlation studies of nanostructured materials' development processes with morphology, structure, and properties represent one of the most important topics today due to potential applications in all fields: chemistry, mechanics, electronics, optics, medicine, food, or defense. Our research was motivated by the fact that in the nanometric domain, the crystalline structure and morphology are determined by the elaboration mechanism. The objective of this paper is to provide an introduction to the fundamentals of nanotechnology and nanopowder production using the sun's energy. Solar energy, as part of renewable energy sources, is one of the sources that remain to be exploited in the future. The basic principle involved in the production of nanopowders consists of the use of a solar energy reactor concentrated on sintered targets made of commercial micropowders. As part of our study, for the first time, we report the solar ablation synthesis and characterization of Ni-doped ZnO performed in the CNRS-PROMES laboratory, UPR 8521, a member of the CNRS (French National Centre for Scientific Research). Also, we study the effect of the elaboration method on structural and morphological characteristics of pure and doped ZnO nanoparticles determined by XRD, SEM, and UV-Vis.

2.
J Clin Med ; 12(19)2023 Sep 25.
Article in English | MEDLINE | ID: mdl-37834836

ABSTRACT

Despite the substantial decrease in mortality rates following a pancreaticoduodenectomy to less than 5%, morbidity rates remain significant, reaching even 73%. Postoperative pancreatic fistula is one of the most frequent major complications and is significantly associated with other complications, including patient death. Currently, there is no consensus regarding the ideal type of pancreatic anastomosis, as the question of the choice between a pancreaticogastrostomy and pancreaticojejunostomy is still open. Furthermore, worldwide implementation of an ideal pancreatic fistula risk prediction score is missing. Our study found several significant predictive factors for the postoperative occurrence of fistulas, such as the soft consistency of the pancreas, non-dilated Wirsung duct, important intraoperative blood loss, other perioperative complications, preoperative patient hypoalbuminemia, and patient weight loss. Our study also revealed that for patients who exhibit fistula risk factors, pancreaticogastrostomy demonstrates a significantly lower pancreatic fistula rate than pancreaticojejunostomy. The occurrence of pancreatic fistulas has been significantly associated with the development of other postoperative major complications, and patient death. As the current pancreatic fistula risk scores proposed by various authors have not been consensually validated, we propose a simple, easy-to-use, and sensitive score for the risk prediction of postoperative pancreatic fistula occurrence based on important predictors from statistical analyses that have also been found to be significant by most of the reported studies. The new pancreatic fistula risk score proposed by us could be extremely useful for improved therapeutic management of cephalic pancreaticoduodenectomy patients.

3.
Sci Rep ; 13(1): 8499, 2023 05 25.
Article in English | MEDLINE | ID: mdl-37231015

ABSTRACT

The Gumelnița site belongs to the Kodjadermen-Gumelnița-Karanovo VI (KGK VI) communities (c. 4700-3900 cal BC) and comprises the tell-type settlement and its corresponding cemetery. This paper reconstructs the diet and lifeways of the Chalcolithic people in the northeastern Balkans using archaeological remains found at the Gumelnița site (Romania). A multi-bioarchaeological investigation (archaeobotany, zooarchaeology, anthropology) was conducted on vegetal, animal, and human remains, alongside radiocarbon dating and stable isotope analyses (δ13C, δ15N) of humans (n = 33), mammals (n = 38), reptiles (n = 3), fishes (n = 8), freshwater mussels shells (n = 18), and plants (n = 24). According to the results of δ13C and δ15N values and FRUITS, the inhabitants of Gumelnița had a diet based on crops and using natural resources, such as fish, freshwater molluscs and game. Although domestic fauna was occasionally exploited for meat, it had a role in providing secondary products. Crops were heavily manured, and chaff and other crop waste may have been necessary fodder for cattle and sheep. Dogs and pigs fed on human waste, although the diet of the latter is more similar to that of wild boars. Foxes had a diet close to dogs, which may indicate synanthropic behaviour. Radiocarbon dates were calibrated with the percentage of freshwater resources obtained by FRUITS. As a result, the corrected dates for the freshwater reservoir effect (FRE) have a delay of an average of 147 years. According to our data, this agrarian community developed a subsistence strategy under the pressure of some climatic changes that started after 4300 cal BC, corresponding to KGK VI rapid collapse/decline episode tracked recently (that begins around 4350 cal BC). This matching of our data in the two models (climatic and chrono-demographic) allowed us to capture the economic strategies that led to the resilience of those people more than other contemporary KGK VI communities.


Subject(s)
Bone and Bones , Isotopes , Humans , Animals , Cattle , Swine , Sheep , Dogs , History, Ancient , Romania , Nitrogen Isotopes/analysis , Bone and Bones/chemistry , Isotopes/analysis , Diet , Cemeteries , Fishes , Carbon Isotopes/analysis , Mammals
4.
Sci Adv ; 9(9): eade2451, 2023 Mar 03.
Article in English | MEDLINE | ID: mdl-36867690

ABSTRACT

The origins of horseback riding remain elusive. Scientific studies show that horses were kept for their milk ~3500 to 3000 BCE, widely accepted as indicating domestication. However, this does not confirm them to be ridden. Equipment used by early riders is rarely preserved, and the reliability of equine dental and mandibular pathologies remains contested. However, horsemanship has two interacting components: the horse as mount and the human as rider. Alterations associated with riding in human skeletons therefore possibly provide the best source of information. Here, we report five Yamnaya individuals well-dated to 3021 to 2501 calibrated BCE from kurgans in Romania, Bulgaria, and Hungary, displaying changes in bone morphology and distinct pathologies associated with horseback riding. These are the oldest humans identified as riders so far.


Subject(s)
Domestication , Humans , Animals , Horses , Reproducibility of Results , Mandible , Milk
5.
Medicina (Kaunas) ; 57(9)2021 Sep 18.
Article in English | MEDLINE | ID: mdl-34577907

ABSTRACT

The atrial septal defect is, after bicuspid aortic valve disease, the most common congenital cardiac disease present in the adult population. The most common atrial septal defects are the ostium secundum type (75-80%), followed by the ostium primum type (15%). The sinus venosus atrial septal defects (SV-ASD), defined as a communication in the posterior part of the interatrial septum, account for about 5 to 10% of atrial septal defects. Approximately 90% of SV-ASDs are associated with partial anomalous pulmonary venous drainage (PAPVD). The minimally invasive approach has gained ground in the treatment of ASDs, especially those of the ostium secundum type. The sinus venosus type is a relatively uncommon form of ASD, which, when associated with a PAPVD, is considered a complex cardiac malformation, and is usually treated in a classical manner, through median sternotomy. We describe the case of a 45-year-old woman diagnosed in adolescence with SV-ASD with PAPVD, who successfully underwent minimally invasive repair with fresh autologous pericardial patch reconstruction through an anterolateral mini-thoracotomy incision. The patient presented with shortness of breath and fatigue after heavy exertions, episodes of paroxysmal nocturnal dyspnea, palpitations during effort and at rest, and had a history of syncope dating from 17 years previously. Echocardiography revealed an SV-ASD with PAPVD in the right atrium and the intraoperative examination discovered that both right pulmonary veins were draining into the superior vena cava.


Subject(s)
Heart Septal Defects, Atrial , Pulmonary Veins , Adolescent , Adult , Drainage , Female , Heart Atria , Heart Septal Defects, Atrial/diagnostic imaging , Heart Septal Defects, Atrial/surgery , Humans , Middle Aged , Pulmonary Veins/diagnostic imaging , Pulmonary Veins/surgery , Vena Cava, Superior
6.
Chirurgia (Bucur) ; 115(2): 267-273, 2020.
Article in English | MEDLINE | ID: mdl-32369732

ABSTRACT

A 52 years old woman, asymptomatic, with no significant medical history, presented to a thoracic surgery department for excision of a giant mediastinal mass that was incidentally detected during a routine abdominal ultrasound. Various imaging methods (echocardiography, chest X-ray, CT-scan, MRI) located the mediastinal mass as paracardiac and the excision using video-assisted thoracoscopic surgery (VATS) was proposed, in general thoracic surgery department. Although initially considered a paracardiac mass, intraoperatively the tumor location proved to be intrapericardial. Reaching the limits of VATS, a median sternotomy and longitudinal pericardiotomy were performed, demonstration a right atrium tumor with intrapericardial extension. At this stage, the excision was considered impossible without cardiopulmonary bypass and cardiac arrest. Having this information, the case was deferred to cardiovascular surgery, one week after and, a complete resection of the tumor was performed without incidents. Both atria were reconstructed with patches of autologous and bovine pericardium. The postoperative outcome of the patient was very good and the histopathology report showed that the tumor was a cavernous hemangioma. The literature was reviewed for this pathology. a rare case of a giant cavernous hemangioma of the heart, with diagnostic pitfalls had a successful multidisciplinary staged approach.


Subject(s)
Heart Neoplasms/surgery , Hemangioma, Cavernous/surgery , Cardiac Surgical Procedures , Female , Heart Atria/diagnostic imaging , Heart Atria/surgery , Heart Neoplasms/diagnostic imaging , Hemangioma, Cavernous/diagnostic imaging , Humans , Middle Aged , Reoperation , Thoracic Surgery, Video-Assisted
7.
Article in English | MEDLINE | ID: mdl-25389163

ABSTRACT

In this paper, we propose a novel ultrasonic tomography method for pipeline flow field imaging, based on the Zernike polynomial series. Having intrusive multipath time-offlight ultrasonic measurements (difference in flight time and speed of ultrasound) at the input, we provide at the output tomograms of the fluid velocity components (axial, radial, and orthoradial velocity). Principally, by representing these velocities as Zernike polynomial series, we reduce the tomography problem to an ill-posed problem of finding the coefficients of the series, relying on the acquired ultrasonic measurements. Thereupon, this problem is treated by applying and comparing Tikhonov regularization and quadratically constrained ℓ1 minimization. To enhance the comparative analysis, we additionally introduce sparsity, by employing SVD-based filtering in selecting Zernike polynomials which are to be included in the series. The first approach-Tikhonov regularization without filtering, is used because it is the most suitable method. The performances are quantitatively tested by considering a residual norm and by estimating the flow using the axial velocity tomogram. Finally, the obtained results show the relative residual norm and the error in flow estimation, respectively, ~0.3% and ~1.6% for the less turbulent flow and ~0.5% and ~1.8% for the turbulent flow. Additionally, a qualitative validation is performed by proximate matching of the derived tomograms with a flow physical model.

8.
Rev Sci Instrum ; 85(11): 114709, 2014 Nov.
Article in English | MEDLINE | ID: mdl-25430135

ABSTRACT

We introduce a new experimental setup with a biasing circuit and computer control for electrical power regulation under reversing polarity in Pt microwires with dimensions of 1×10 µm(2). The circuit is computer controlled via a data acquisition board. It amplifies a control signal from the computer and drives current of alternating polarity through the sample in question. Time-to-failure investigations under DC and AC current stress are performed. We confirm that AC current stress can improve the life time of microwires at least by a factor of 10(3) compared to the corresponding time-to-failure under DC current stress.

9.
J Opt Soc Am A Opt Image Sci Vis ; 21(8): 1455-64, 2004 Aug.
Article in English | MEDLINE | ID: mdl-15330474

ABSTRACT

A new method for filtering the coherence map issued from synthetic aperture radar (SAR) interferometric data is presented. For each pixel of the interferogram, an adaptive neighborhood is determined by a region-growing technique driven by the information provided by the amplitude images. Then pixels in the derived adaptive neighborhood are complex averaged to yield the filtered value of the coherence, after a phase-compensation step is performed. An extension of the algorithm is proposed for polarimetric interferometric SAR images. The proposed method has been applied to both European Remote Sensing (ERS) satellite SAR images and airborne high-resolution polarimetric interferometric SAR images. Both subjective and objective performance analysis, including coherence edge detection, shows that the proposed method provides better results than the standard phase-compensated fixed multilook filter and the Lee adaptive coherence filter.

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