1,480 research outputs found
Back-to-back azimuthal correlations in Z+jet events at high transverse momentum in the TMD parton branching method at next-to-leading order
Azimuthal correlations in Z+jet production at large transverse momenta are
computed by matching Parton - Branching (PB) TMD parton distributions and
showers with NLO calculations via MCatNLO. The predictions are compared with
those for dijet production in the same kinematic range. The azimuthal
correlations between the Z boson and the leading jet are steeper
compared to those in dijet production at transverse momenta GeV
, while they become similar for very high transverse momenta
GeV. The different patterns of Z+jet and dijet azimuthal correlations can be
used to search for potential factorization - breaking effects in the
back-to-back region, which depend on the different color and spin structure of
the final states and their interferences with the initial states. In order to
investigate these effects experimentally, we propose to measure the ratio of
the distributions in for Z+jet - and multijet production at low
and at high transverse momenta, and compare the results to predictions obtained
assuming factorization. We examine the role of theoretical uncertainties by
performing variations of the factorization scale, renormalization scale and
matching scale. In particular, we present a comparative study of matching scale
uncertainties in the cases of PB -TMD and collinear parton showers
Pseudoaneurysm due to femoral artery puncture: a review
The femoral artery is the most used percutaneous access site for different endovascular therapeutic options, this being an excellent anatomical site to achieve adequate compression after its puncture, which frequently makes it the site with the highest incidence of complications associated with posterior to arterial puncture. The most frequent complications related to arterial puncture are: hematoma, pseudoaneurysm, retroperitoneal hematoma, and arterial occlusion. The pseudoaneurysm is defined as the interruption in the wall of the artery, product of the lesion of the wall, which causes blood leakage towards the surrounding tissues, remaining contained in a fibrin sac, therefore, the importance of an adequate diagnosis and treatment lies above all in the high risk of rupture or thromboembolism.
Hypospadias: a review
Hypospadias is a congenital malformation of the male external genitalia, which includes: anomalous location proximal to the urethral meatus, in any portion of the glans penis and perineum, hooded dorsal foreskin, and inverted penile curvature on the dorsal side of the foreskin. The etiology has been considered multifactorial, secondary to the interaction of environmental factors with specific genetic background. It represents the second most frequent congenital defect in male newborns. It has increasing prevalence rates of 0.25 new cases per 10,000 newborns per year. Risk factors that have been identified include infants small for gestational age with weight below the 10th percentile, head length and/or circumference, intrauterine growth restriction, and placental insufficiency. Regarding environmental risk factors, maternal exposure to pesticides has been linked. Prenatal diagnosis has been described, however proximal hypospadias is usually detected, making it difficult to diagnose distal hypospadias using this method. So usually the diagnosis is made after birth during the physical examination. To date, more than 300 surgical techniques are known for the correction of hypospadias. The treatment of distal hypospadias is currently performed in one time; the management of proximal hypospadias is controversial; one group favors the one-stage procedure, while other groups choose to perform the two-stage procedure
Staghorn renal stones: a review
Staghorn lithiasis is described as the presence of stones in the urinary tract that create a mold of the renal collecting system, with the characteristic of being branched. It has a strong association with urinary tract infections caused by urea-splitting organisms. The composition of the stone usually consists of pure magnesium ammonium phosphate (struvite), or a mixture of struvite and calcium carbonate apatite. It is classified as complete and partial. In the complete one, the stones occupy the renal pelvis and the calyceal system, or more than 80% of the collecting system; unlike the partial ones that occupy the renal pelvis and at least two calyces. Computed tomography without intravenous contrast is the imaging method of choice for diagnosis and planning of surgical intervention. Allowing an accurate assessment of the morphology and location of the stones; that will set the standard for guiding percutaneous access. Complete stone cleaning is the cornerstone of staghorn lithiasis treatment. The guidelines of the European Association of Urology and the American Association of Urology mention that percutaneous nephrolithotomy continues to be the treatment of choice for large stones. Conservative management is related to renal loss and urosepsis, reporting a mortality of 28 % up to 30% within 10 years, as well as a 36% risk of developing chronic kidney disease
Xanthogranulomatous pyelonephritis: a review
Xanthogranulomatous pyelonephritis (XP), first described in 1916, is a rare form of chronic granulomatous inflammation. The etiology is still unclear; however, the development of the disease is associated with chronic urinary obstruction secondary to lithiasis, tumors and urological malformations, among others. This leads to the destruction of the renal parenchyma and its replacement by solid sheets of lipid-laden macrophages. Female gender, diabetes and obesity are attributed as predisposing factors to the development of XP. It is estimated that the incidence presents a maximum peak between 50 and 70 years, with a ratio of 2:1 women-men respectively. Computed tomography (CT) is described as the mainstay in the evaluation. However, the definitive diagnosis is made by histopathological study, where a mixture of lipid-laden foamy macrophages, lymphocytes, neutrophils, giant cells, and plasma cells can be seen. Nephrectomy (open or laparoscopic) continues to be the first-line treatment. The laparoscopic approach is associated with an increase in operating time; however, the recovery time is shorter compared to the open approach. Given the natural history of the disease and the associated complications, this makes it a challenging approach for the surgeon. Therefore, a surgeon experienced in laparoscopic skills is necessary. This review seeks to synthesize existing information regarding the appropriate surgical approach in conjunction with the clinical context
Biliary atresia: a review
Bile duct atresia (BA) is a severe, progressive cholangiopathy characterized by fibrous and inflammatory obliteration of the intrahepatic and extrahepatic bile ducts. It leads to liver failure, scarring, and end-stage cirrhosis if timely treatment is not achieved. It represents the number one indication for pediatric liver transplantation as a single disease worldwide. Various etiological factors have been associated with BA, such as structural malformations, viral, immune-mediated, and genetic infections. The incidence of BA varies around the world. Untreated BA patients have a 2-year mortality of nearly 100%. The clinical picture is characterized by jaundice, acholia, and jaundice that persists beyond the first 2 weeks of life. Direct or conjugated bilirubin remains the primary screening laboratory test for BA; elevated values ​​occur within the first 2 days of life. Currently, the primary treatment of choice is the Kasai portoenterostomy; the success of surgery has been based on the restoration of bile flow and the elimination of jaundice. However, more than 70% of patients develop liver cirrhosis secondary to persistent liver inflammation, which will require liver transplantation. The following review of the literature aims to collect relevant information from what has been published in recent years on bile duct atresia; focused on the study of etiology, pathophysiology, advances in genetics and immunology. As well as the results associated with surgical treatment and the requirement for liver transplantation
Hidradenitis suppurativa: a review
Hidradenitis suppurativa (HS) is a chronic inflammatory disorder that is characterized by recurrence, as well as the characteristic location of skin lesions. Patients usually develop very painful inflammatory nodules that generally end in the formation of multiple abscesses and fistulas that typically occur in the skin of the axillary, inguinal, buttock, and perianal folds. It significantly affects the quality of life of patients, leaving physical, economic and psychological sequelae. There is a wide therapeutic arsenal available, but each patient must be individualized and the best possible treatment determined. Early assessment and intensive treatment of the disease can prevent and even avoid significant sequelae and permanent deformities
Current strategies for the reconstruction of the nipple-areola complex: a review
The reconstruction of the nipple-areola complex after a mastectomy is essential for the bio-psycho-social recovery of the patient, it is generally performed 4 to 6 months after surgery and there are multiple surgical reconstruction techniques depending on the experience of the surgeon and of the individual characteristics of the patients. The most widely used for its safety and for having shown the best results is the local flap technique combined with the use of autologous, alloplastic and allograft grafts. However, currently there is still no technique that shows long-term lasting results. For this reason, in this article we describe the five categories of reconstruction techniques for the nipple-areola complex that currently exist, their advantages and disadvantages, as well as the lines of research in tissue engineering in which the world is working to find a therapeutic strategy that can reproduce a nipple-areola complex with the characteristics of the biologic.
Biodegradable electrospun scaffolds for skin wound regeneration: a review
Over the years, skin substitutes have been sought as an alternative for the treatment of different pathologies. In this article, we focus on describing the use of different biodegradable nanofibrillar polymers as skin substitutes in the treatment of acute and chronic wounds, obtained by the electrospinning technique. Electrospinning is a tissue engineering technique used to generate nanofibers of different polymers that are characterized by having a high surface area, low molecular weight, high resistance rates, and nanoporosity, which is why they are particularly interesting for biomedicine, with potential applicability. in the replacement of skin and tubular organs. In this context, the skin created by tissue engineering has high expectations of application in the study of treatment of skin wounds
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