^{140}Ce(n,γ) is a key reaction for slow neutron-capture (s-process) nucleosynthesis due to being a bottleneck in the reaction flow. For this reason, it was measured with high accuracy (uncertainty ≈5%) at the n_TOF facility, with an unprecedented combination of a high purity sample and low neutron-sensitivity detectors. The measured Maxwellian averaged cross section is up to 40% higher than previously accepted values. Stellar model calculations indicate a reduction around 20% of the s-process contribution to the Galactic cerium abundance and smaller sizeable differences for most of the heavier elements. No variations are found in the nucleosynthesis from massive stars.
- Publikační typ
- časopisecké články MeSH
PURPOSE OF THE STUDY: This manuscript aims to present the method of arthroscopic assisted subtalar arthrodesis and to evaluate the benefi ts of this surgery on our study population. MATERIAL AND METHODS: In the period from 9/2007 to 1/2020, a total of 33 subtalar arthrodesis were performed in 31 patients aged 19-66 years (mean 48 years, median 50 years). The indication for arthrodesis was subtalar arthritis causing pain and gait disorders, or hindfoot deformities (most commonly after a calcaneus bone fracture). The arthroscopic assisted subtalar arthrodesis was performed with autologous tricortical bone block graft harvesting from the pelvis, supplemented by autologous cancellous bone graft. Stabilization was achieved by cannulated screws inserted in neutral ankle position. Patients in our retrospective study were followed up for a mean of 48 months (range, 24-130 months). The patients were evaluated preoperatively and at 2 years after surgery. The hindfoot angles and height (TCA - talocalcaneal angle, CIA - calcaneal inclination angle, TCH - talocalcaneal height) were evaluated on radiographs, bone union was assessed on radiographs and CT scans. The clinical assessment was performed using the ankle-hindfoot scale (AHS) of AOFAS (AOFAS score). RESULTS: The preoperative AOFAS score was 35-68 points (mean 52, median 54), the postoperative AOFAS score at 2 years after arthrodesis was 58-94 points (mean 82, median 82). Both the mean and median values of AOFAS score showed a signifi - cant progress from the poor result to the good and excellent result. After 2 years the TCA value decreased in 18 patients (56%) by no more than 3°. The CIA decrease observed in 21 patients (64%) was by 1° on average. The TCH decrease of 1-5 mm after 2 years since the surgery was seen in 16 patients. In 2 patients incomplete healing of arthrodesis was observed, manifested as a clinically asymptomatic non-union. No deep infection was reported. DISCUSSION: In agreement with the current literature, the arthroscopic subtalar arthrodesis has been confi rmed to be a safe method for the management of consequences of hindfoot fractures, with minimum complications and leading to accelerated bone fusion. Differences can be found in the approach, position, use of cancellous bone graft and surgical techniques. In recent years, prone position, posterior approaches, use of cancellous bone graft, distraction and fi xation with 2-3 screws divergently inserted into the bone prevail. The degree of healing of the bone fusion is generally an important factor. In our study population, non-healing was recorded in 2 patients, namely in the form of a clinically silent non-union. Neurological or early complications and/or osteosynthesis material failure occurred in up to a maximum of 10% of cases. The conclusive results of minimally invasive arthrodesis based on the AOFAS score have been confi rmed by us as well as by most authors. CONCLUSSIONS: Our study confi rmed that the arthroscopic assisted subtalar arthrodesis is a successful, reliable and safe minimally invasive method, with minimum complications, leading to stable arthrodesis. KEY WORDS: subtalar arthrodesis, subtalar arthroscopy.
- MeSH
- artrodéza MeSH
- dolní končetina MeSH
- fraktury kostí * MeSH
- lidé MeSH
- noha (od hlezna dolů) MeSH
- patní kost * chirurgie MeSH
- poranění kotníku * MeSH
- retrospektivní studie MeSH
- Check Tag
- lidé MeSH
- Publikační typ
- anglický abstrakt MeSH
- časopisecké články MeSH
INTRODUCTION: The study identifies risk factors predicting cervical spine fracture on CT based on information in the referral form. METHODS: All patients aged over 18 years with a CT scan of the head and cervical spine completed at the University Hospital Brno in the year 2019 to exclude any fresh trauma were included in the retrospective study. The analyzed potential risk factors included gender, age over 65 years, unconsciousness or impaired consciousness, mechanism of injury, paresthesia or plegia suspected to be associated with trauma, cervical spine pain, other neurological symptomatology, presence of cervical collar, presence of intracranial hemorrhage on head CT, and presence of skull fracture on head CT. RESULTS: In total, a cervical or upper thoracic spine fracture was described in 51 of 1177 patients (4.3%). Statistically significant risk factors for cervical spine fracture on CT scan were identified as mechanism of injury similar to car accident or jumping into water (OR 2.52; p=0.004), pain of the cervical spine (OR 1.81; p.
- Klíčová slova
- X-ray, cervical spine, computed tomography, doppler ultrasound of uterine artery, risk factors, trauma,
- MeSH
- dospělí MeSH
- fraktury páteře * diagnostické zobrazování etiologie MeSH
- krční obratle diagnostické zobrazování zranění MeSH
- lidé středního věku MeSH
- lidé MeSH
- počítačová rentgenová tomografie škodlivé účinky MeSH
- poranění hrudníku * komplikace MeSH
- retrospektivní studie MeSH
- senioři MeSH
- Check Tag
- dospělí MeSH
- lidé středního věku MeSH
- lidé MeSH
- senioři MeSH
- Publikační typ
- časopisecké články MeSH
Neutron capture reaction cross sections on 74 Ge are of importance to determine 74 Ge production during the astrophysical slow neutron capture process. We present new resonance data on 74 Ge( n , γ ) reactions below 70 keV neutron energy. We calculate Maxwellian averaged cross sections, combining our data below 70 keV with evaluated cross sections at higher neutron energies. Our stellar cross sections are in agreement with a previous activation measurement performed at Forschungszentrum Karlsruhe by Marganiec et al., once their data has been re-normalised to account for an update in the reference cross section used in that experiment.
- Publikační typ
- časopisecké články MeSH
Nowadays, free flap reconstruction in devastating lower limb trauma is a standard procedure in reconstructive surgery. The greatest factor directly affecting limb salvage is still the risk of infectious complications, whether local or systemic. Fungal wound infections are not among the most common infection complications in surgery, but their low incidence is compensated for by their fulminant and serious course, as well as severe local tissue destruction and strong angio-invasive potential together with the possibility of dissemination. In this case study, we present an example of a devastating lower leg injury, solved using latissimus free flap reconstruction, with subsequent difficult and prolonged healing, due to an invasive filamentous fungi infection. In the final part of the article, we focus briefly on the occurrence of similar cases in the literature.
- Klíčová slova
- filamentous fungi, free flap, infection, reconstruction,
- MeSH
- fusarióza * MeSH
- lidé MeSH
- Mucor MeSH
- poranění nohy (od hlezna dolů) * chirurgie MeSH
- retrospektivní studie MeSH
- volné tkáňové laloky * MeSH
- výsledek terapie MeSH
- zákroky plastické chirurgie * MeSH
- Check Tag
- lidé MeSH
- Publikační typ
- časopisecké články MeSH
The neutron capture cross sections of several unstable nuclides acting as branching points in the s process are crucial for stellar nucleosynthesis studies. The unstable ^{171}Tm (t_{1/2}=1.92 yr) is part of the branching around mass A∼170 but its neutron capture cross section as a function of the neutron energy is not known to date. In this work, following the production for the first time of more than 5 mg of ^{171}Tm at the high-flux reactor Institut Laue-Langevin in France, a sample was produced at the Paul Scherrer Institute in Switzerland. Two complementary experiments were carried out at the neutron time-of-flight facility (n_TOF) at CERN in Switzerland and at the SARAF liquid lithium target facility at Soreq Nuclear Research Center in Israel by time of flight and activation, respectively. The result of the time-of-flight experiment consists of the first ever set of resonance parameters and the corresponding average resonance parameters, allowing us to make an estimation of the Maxwellian-averaged cross sections (MACS) by extrapolation. The activation measurement provides a direct and more precise measurement of the MACS at 30 keV: 384(40) mb, with which the estimation from the n_TOF data agree at the limit of 1 standard deviation. This value is 2.6 times lower than the JEFF-3.3 and ENDF/B-VIII evaluations, 25% lower than that of the Bao et al. compilation, and 1.6 times larger than the value recommended in the KADoNiS (v1) database, based on the only previous experiment. Our result affects the nucleosynthesis at the A∼170 branching, namely, the ^{171}Yb abundance increases in the material lost by asymptotic giant branch stars, providing a better match to the available pre-solar SiC grain measurements compared to the calculations based on the current JEFF-3.3 model-based evaluation.
- Publikační typ
- časopisecké články MeSH
Superior Shoulder Suspensory Complex (SSSC) is a bone and soft-tissue ring securing the connection of the upper extremity to the axial skeleton via the clavicle and sternoclavicular joint. An isolated injury to one component of SSSC is usually stable. An injury to 2 of its components is a potential source of shoulder girdle instability and requires surgical stabilisation. An injury affecting 3 and more components is extremely rare and surgical stabilisation should be indicated. Our study presents the case of a 50-year-old man who fell off the bicycle and sustained a direct blow to his left shoulder resulting in an ipsilateral fracture of the coracoid and acromion process combined with the fracture of the distal end of the clavicle. Following a standard clinical examination and a subsequent X-ray and a CT scan with three-dimensional shoulder reconstruction, an open reduction and stabilisation of all the injured SSSC components was performed. Later, early and gradual rehabilitation of the shoulder girdle was commenced. At 48 weeks after the surgery, almost full range of motion of the shoulder joint was achieved and the muscle strength of the operated upper extremity was comparable to that of the healthy one. Key words:Superior Shoulder Suspensory Complex, fracture, acromion, coracoid process, clavicle.
- MeSH
- akromion diagnostické zobrazování zranění MeSH
- fraktury kostí diagnostické zobrazování rehabilitace chirurgie MeSH
- klíční kost diagnostické zobrazování zranění MeSH
- lidé středního věku MeSH
- lidé MeSH
- lopatka diagnostické zobrazování zranění MeSH
- poranění ramene diagnostické zobrazování rehabilitace chirurgie MeSH
- processus coracoideus diagnostické zobrazování zranění MeSH
- vnitřní fixace fraktury MeSH
- Check Tag
- lidé středního věku MeSH
- lidé MeSH
- mužské pohlaví MeSH
- Publikační typ
- časopisecké články MeSH
- kazuistiky MeSH
PURPOSE OF THE STUDY The aim of our study is to show the pitfalls of performing skull X-rays in patients with head injuries and the lack of accuracy of this examination nowadays, and to clarify the current trend in the MTBI investigation algorithm. MATERIAL AND METHODS A retrospective study of 3,950 patients treated for acute head injury at the Department of Trauma Surgery (University Hospital Brno) in the period from 2015 to 2016. Inclusion criteria were the following: mild brain injury (GCS = 15), primary skull X-ray design in head injury diagnosis. Patients with a positive skull X-ray finding underwent a head CT evaluation up to 24-hours from the injury except for the patients with an isolated nose bone fracture. A CT head scan was also performed in patients indicated by the neurologist at the initial examination based on the anamnestic data and an objective finding. RESULTS Inclusion criteria were met by 1,938 patients. In 1806 (93.2%) cases the X-ray was negative, in 132 (6.8%) patients the X-ray was positive, of which in 62% of patients a nasal fracture was detected. A skull fracture reported in 16 cases. Once the CT scan of the head was obtained, all of these cases were classified as false negative. After the CT scan of the head, intracranial bleeding was observed in 12 patients, in 4 cases accompanied by fractures of the skull, not visible on the X-ray images. After the statistical evaluation, the sensitivity and specificity of the X-ray examination compared to the CT scan of the head was determined to be 0.00 and 0.94, respectively. DISCUSSION The aim of MTBI diagnostics is primarily to detect serious intracranial lesions requiring neurosurgical intervention. A simple X-ray of the skull shows fractures only and does not allow to visualize both the brain and any traces of bleeding that would show an intracranial injury. Hofman, in his meta-analysis, points out that a simple X-ray image of the skull has only very little noticeable value when diagnosing MTBI. The prevalence of intracerebral hematoma (ICH) over MTBI is 0.083. The sensitivity of a radiographic finding of skull fracture in the diagnosis of ICH based on the CT verification is only 0.38 with a specificity of 0.95, which is consistent with our study where the sensitivity of the radiographic finding was 0.00 with a specificity of 0.94 relative to CT. Thus, the question is not whether to perform an X-ray of the skull in mild head injuries, but rather when to indicate a CT scan of the brain, when to admit the patient to the hospital for observation, and for how long or when the patient can be safely discharged into home care. The purpose of MTBI diagnostics, however, should not be a rashly decision to perform a brain CT scan, but to put into practice the CT indication criteria in MTBI applying and respecting the validated guidelines known worldwide. CONCLUSIONS Our study, in which no X-ray examination revealed possible intracranial bleeding, clearly shows that nowadays the plain radiograph of the skull does not bring any benefit in the diagnosis of minor traumatic brain injury. Key words:skull X-ray, CT of the head, head injury, minor traumatic brain injury.
- MeSH
- algoritmy MeSH
- fraktury lebky diagnostické zobrazování etiologie MeSH
- kraniocerebrální traumata komplikace diagnostické zobrazování MeSH
- lebka diagnostické zobrazování MeSH
- lidé MeSH
- mozek diagnostické zobrazování MeSH
- počítačová rentgenová tomografie MeSH
- poranění mozku diagnostické zobrazování MeSH
- rentgenové záření MeSH
- retrospektivní studie MeSH
- Check Tag
- lidé MeSH
- Publikační typ
- časopisecké články MeSH
We report on the measurement of the ^{7}Be(n,p)^{7}Li cross section from thermal to approximately 325 keV neutron energy, performed in the high-flux experimental area (EAR2) of the n_TOF facility at CERN. This reaction plays a key role in the lithium yield of the big bang nucleosynthesis (BBN) for standard cosmology. The only two previous time-of-flight measurements performed on this reaction did not cover the energy window of interest for BBN, and they showed a large discrepancy between each other. The measurement was performed with a Si telescope and a high-purity sample produced by implantation of a ^{7}Be ion beam at the ISOLDE facility at CERN. While a significantly higher cross section is found at low energy, relative to current evaluations, in the region of BBN interest, the present results are consistent with the values inferred from the time-reversal ^{7}Li(p,n)^{7}Be reaction, thus yielding only a relatively minor improvement on the so-called cosmological lithium problem. The relevance of these results on the near-threshold neutron production in the p+^{7}Li reaction is also discussed.
- Publikační typ
- časopisecké články MeSH
The energy-dependent cross section of the ^{7}Be(n,α)^{4}He reaction, of interest for the so-called cosmological lithium problem in big bang nucleosynthesis, has been measured for the first time from 10 meV to 10 keV neutron energy. The challenges posed by the short half-life of ^{7}Be and by the low reaction cross section have been overcome at n_TOF thanks to an unprecedented combination of the extremely high luminosity and good resolution of the neutron beam in the new experimental area (EAR2) of the n_TOF facility at CERN, the availability of a sufficient amount of chemically pure ^{7}Be, and a specifically designed experimental setup. Coincidences between the two alpha particles have been recorded in two Si-^{7}Be-Si arrays placed directly in the neutron beam. The present results are consistent, at thermal neutron energy, with the only previous measurement performed in the 1960s at a nuclear reactor. The energy dependence reported here clearly indicates the inadequacy of the cross section estimates currently used in BBN calculations. Although new measurements at higher neutron energy may still be needed, the n_TOF results hint at a minor role of this reaction in BBN, leaving the long-standing cosmological lithium problem unsolved.
- Publikační typ
- časopisecké články MeSH
