ABSTRACT
In nonlinear Thomson scattering, a relativistic electron reradiates the photons of a laser pulse, converting optical light to x rays or beyond. While this extreme frequency conversion offers a promising source for probing high-energy-density materials and driving uncharted regimes of nonlinear quantum electrodynamics, conventional nonlinear Thomson scattering has inherent trade-offs in its scaling with laser intensity. Here we discover that the ponderomotive control afforded by spatiotemporal pulse shaping enables regimes of nonlinear Thomson scattering that substantially enhance the scaling of the radiated power, emission angle, and frequency with laser intensity. By appropriately setting the velocity of the intensity peak, a spatiotemporally shaped pulse can increase the power radiated by orders of magnitude. The enhanced scaling with laser intensity allows for operation at significantly lower electron energies or intensities.
ABSTRACT
BACKGROUND: Data regarding the prevalence of metallo-ß-lactamases (MBLs) among Pseudomonas aeruginosa isolates in cystic fibrosis patients are scarce. Furthermore, there is limited knowledge on the effect of MBL production on patient outcomes. Here we describe a fatal respiratory infection due to P. aeruginosa producing VIM-type MBLs in a lung transplant recipient and the results of the subsequent epidemiological investigation. CASE PRESENTATION: P. aeruginosa isolates collected in the index patient and among patients temporally or spatially linked with the index patient were analyzed in terms of antibiotic susceptibility profile and MBL production. Whole-genome sequencing and phylogenetic reconstruction were also performed for all P. aeruginosa isolates producing VIM-type MBLs. A VIM-producing P. aeruginosa strain was identified in a lung biopsy of a lung transplant recipient with cystic fibrosis. The strain was VIM-1-producer and belonged to the ST308. Despite aggressive treatment, the transplant patient succumbed to the pulmonary infection due to the ST308 strain. A VIM-producing P. aeruginosa strain was also collected from the respiratory samples of a different cystic fibrosis patient attending the same cystic fibrosis center. This isolate harbored the blaVIM-2 gene and belonged to the clone ST175. This patient did not experience an adverse outcome. CONCLUSIONS: This is the first description of a fatal infection due to P. aeruginosa producing VIM-type MBLs in a lung transplant recipient. The circulation of P. aeruginosa isolates harboring MBLs pose a substantial risk to the cystic fibrosis population due to the limited therapeutic options available and their spreading potential.
Subject(s)
Anti-Bacterial Agents/therapeutic use , Lung Transplantation , Pseudomonas Infections/drug therapy , Pseudomonas aeruginosa/enzymology , Respiratory Tract Infections/drug therapy , Transplant Recipients , Adult , Cystic Fibrosis/surgery , Drug Resistance, Multiple, Bacterial/drug effects , Fatal Outcome , Female , Humans , Lung/microbiology , Lung/pathology , Microbial Sensitivity Tests , Phylogeny , Pseudomonas Infections/microbiology , Pseudomonas aeruginosa/isolation & purification , Respiratory Tract Infections/microbiology , beta-Lactamases/genetics , beta-Lactamases/metabolismABSTRACT
Primary hepatic malignancies in non-cirrhotic liver include a wide spectrum of tumors, which are classified based on their cells of origin. Hepatocellular carcinoma is the most common primary malignant tumor, followed by intrahepatic cholangiocarcinoma. Beside these tumors, other primary malignancies in the non-cirrhotic liver are quite rare. Accurate diagnosis is often difficult with imaging alone and biopsy with further histopathological analysis is often necessary. However, many of these tumors exhibit suggestive or characteristic imaging features due to their different cellular components, allowing radiologists to suggest the correct diagnosis. Thus, the aim of this article is to provide an overview of imaging presentation of primary malignant liver tumors that develop in the non-cirrhotic liver, including potential differential diagnoses. Such knowledge is essential as it may contribute to accurate radiological diagnosis and improved patient outcome.
Subject(s)
Bile Duct Neoplasms , Carcinoma, Hepatocellular , Cholangiocarcinoma , Liver Neoplasms , Bile Duct Neoplasms/diagnostic imaging , Carcinoma, Hepatocellular/diagnostic imaging , Cholangiocarcinoma/diagnostic imaging , Diagnostic Imaging , Humans , Liver/diagnostic imaging , Liver Neoplasms/diagnostic imaging , Magnetic Resonance ImagingABSTRACT
Processes occurring in the strong field regime of QED are characterized by background electromagnetic fields of the order of the critical field F_{cr}=m^{2}c^{3}/â|e| in the rest frame of participating charges. It has been conjectured that if in their rest frame electrons and positrons experience field strengths of the order of F_{cr}/α^{3/2}≈1600F_{cr}, with α≈1/137 being the fine-structure constant, their effective coupling with radiation becomes of the order of unity. Here we show that channeling radiation by ultrarelativistic electrons with energies of the order of a few TeV on thin tungsten crystals allows us to test the predictions of QED close to this fully nonperturbative regime by measuring the angularly resolved single photon intensity spectrum. The proposed setup features the unique characteristics that essentially all electrons (1) undergo at most a single photon emission and (2) experience at the moment of emission and in the angular region of interest the maximum allowed value of the field strength, which at 2 TeV exceeds F_{cr} by more than 2 orders of magnitude in their rest frame.
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European populations display low genetic differentiation as the result of long-term blending of their ancient founding ancestries. However, it is unclear how the combination of ancient ancestries related to early foragers, Neolithic farmers, and Bronze Age nomadic pastoralists can explain the distribution of genetic variation across Europe. Populations in natural crossroads like the Italian peninsula are expected to recapitulate the continental diversity, but have been systematically understudied. Here, we characterize the ancestry profiles of Italian populations using a genome-wide dataset representative of modern and ancient samples from across Italy, Europe, and the rest of the world. Italian genomes capture several ancient signatures, including a non-steppe contribution derived ultimately from the Caucasus. Differences in ancestry composition, as the result of migration and admixture, have generated in Italy the largest degree of population structure detected so far in the continent, as well as shaping the amount of Neanderthal DNA in modern-day populations.
Subject(s)
DNA, Ancient , Databases, Genetic , Genetic Drift , Genome, Human , White People/genetics , Animals , Genome-Wide Association Study , History, Ancient , Human Genetics , Humans , Italy , Neanderthals/geneticsABSTRACT
Targeted GBS is a recent approach for obtaining an effective characterization for hundreds to thousands of markers. The high throughput of next-generation sequencing technologies, moreover, allows sample multiplexing. The aims of this study were to (i) define a panel of single nucleotide polymorphisms (SNPs) in the cat, (ii) use GBS for profiling 16 cats, and (iii) evaluate the performance with respect to the inference using standard approaches at different coverage thresholds, thereby providing useful information for designing similar experiments. Probes for sequencing 230 variants were designed based on the Felis_catus_8.0. 8.0 genome. The regions comprised anonymous and non-anonymous SNPs. Sixteen cat samples were analysed, some of which had already been genotyped in a large group of loci and one having been whole-genome sequenced in the 99_Lives Cat Genome Sequencing Project. The accuracy of the method was assessed by comparing the GBS results with the genotypes already available. Overall, GBS achieved good performance, with 92-96% correct assignments, depending on the coverage threshold used to define the set of trustable genotypes. Analyses confirmed that (i) the reliability of the inference of each genotype depends on the coverage at that locus and (ii) the fraction of target loci whose genotype can be inferred correctly is a function of the total coverage. GBS proves to be a valid alternative to other methods. Data suggested a depth of less than 11× is required for greater than 95% accuracy. However, sequencing depth must be adapted to the total size of the targets to ensure proper genotype inference.
Subject(s)
Cats/genetics , Animals , Genome , Genotyping Techniques , Microsatellite Repeats , Polymorphism, Single NucleotideABSTRACT
Accelerated charges emit electromagnetic radiation. According to classical electrodynamics, if the charges move along sufficiently close trajectories they emit coherently; i.e., their emitted energy scales quadratically with their number rather than linearly. By investigating the emission by a two-electron wave packet in the presence of an electromagnetic plane wave within strong-field QED, we show that quantum effects deteriorate the coherence predicted by classical electrodynamics even if the typical quantum nonlinearity parameter of the system is much smaller than unity. We explain this result by observing that coherence effects are also controlled by a new quantum parameter which relates the recoil undergone by the electron to the width of its wave packet in momentum space.
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Clivus fractures are usually associated with head blunt trauma due to traffic accident and falls. A 23 - year-old man died immediately after a smash-up while he was stopping on his motorcycle. Post-mortem Computed tomography (PMCT), performed before autopsy, revealed a complex basilar skull base fractures associated with brainstem and cranio-vertebral junction injuries, improving the diagnostic performance of conventional autopsy. Imaging data were re-assessable and PMCT offers the possibility to perform multiplanar and volume rendered reconstructions, increasing forensic medicine knowledge related to traumatic injuries.
Subject(s)
Death , Skull Fractures , Tomography, X-Ray Computed , Accidents, Traffic , Autopsy , Brain Stem/pathology , Forensic Pathology , Humans , Male , Young AdultABSTRACT
El ergotismo es en la actualidad un trastorno raro, asociado a la administración iatrogénica de ergotamina en pacientes que padecen de cefaleas migrañosas. La intensidad del vasoespasmo que presenta esta entidad clínica en la mayoría de los casos resulta en isquemia aguda de las extremidades. Presentamos 2 casos de isquemia aguda de las extremidades, en pacientes de sexo femenino, de mediana edad, con signos y síntomas que amenazaban la viabilidad de los miembros inferiores. El estudio por ultrasonido y la arteriografía (en el caso 1) confirmaron la presencia de espasmo arterial bilateral difuso. Inmediatamente se procedió a interrumpir la administración de ergotamina y se instauró terapia vasodilatadora. Los síntomas de las pacientes empezaron a mejorar a las 48-72 h de iniciado el tratamiento (AU)
Ergotism is a rare disorder associated with the iatrogenic administration of ergotamine in patients with migraine headaches. The intense vasospasm that occurs in this clinical condition results in acute limb ischaemia in the majority of cases. Two cases are presented of acute limb ischaemia in middle age female patients with signs and symptoms that threatened the viability of lower limbs. Duplex ultrasound and arteriography (in the first case) confirmed the presence of a bilateral diffuse arterial spasm. Ergotamine treatment was discontinued immediately and vasodilator therapy was administered. The patient's symptoms began to improve 48-72 h after starting therapy (AU)
Subject(s)
Humans , Female , Adult , Ischemia/chemically induced , Lower Extremity/physiopathology , Ergotamine/adverse effects , Vasodilator Agents/adverse effects , Ergotism/diagnosis , Tobacco Use Disorder/complicationsSubject(s)
Escherichia coli Infections/microbiology , Extraintestinal Pathogenic Escherichia coli/enzymology , beta-Lactamases/biosynthesis , Aged , Extraintestinal Pathogenic Escherichia coli/drug effects , Extraintestinal Pathogenic Escherichia coli/isolation & purification , Fatal Outcome , Female , Humans , Italy , Male , Middle AgedABSTRACT
Y-chromosomal variation of selected single nucleotide polymorphisms (SNPs) and 32 short tandem repeat (STR) loci was evaluated in Sardinia in three open population groups (Northern Sardinia, n=40; Central Sardinia, n=56; Southern Sardinia, n=91) and three isolates (Desulo, n=34; Benetutti, n=45, Carloforte, n=42). The tested Y-STRs consisted of Yfiler® Plus markers and the seven rapidly mutating (RM) loci not included in the YFiler® Plus kit (DYF399S1, DYF403S1ab, DYF404S1, DYS526ab, DYS547, DYS612, and DYS626). As expected, inclusion of additional Y-STR loci increased haplotype diversity (h), though complete differentiation of male lineages was impossible even by means of RM Y-STRs (h=0.99997). Analysis of molecular variance indicated that the three open populations were fairly homogeneous, whereas signs of genetic heterogeneity could be detected when the three isolates were also included in the analysis. Multidimensional scaling analysis showed that, even for extended haplotypes including RM Y-STR markers, Sardinians were clearly differentiated from populations of the Italian peninsula and Sicily. The only exception was represented by the Carloforte sample that, in accordance with its peculiar population history, clustered with Northern/Central Italian populations. The introduction of extended forensic Y-STR panels, including highly variable RM Y-STR markers, is expected to reduce the impact of population structure on haplotype frequency estimations. However, our results show that the availability of geographically detailed reference databases is still important for the assessment of the evidential value of a Y-haplotype match.
Subject(s)
Chromosomes, Human, Y , Genetics, Population , Haplotypes , Microsatellite Repeats , DNA Fingerprinting , Humans , Italy , Male , Polymerase Chain Reaction , Polymorphism, Single NucleotideABSTRACT
The only available analytical framework for investigating QED processes in a strong laser field systematically relies on approximating the latter as a plane wave. However, realistic high-intensity laser beams feature much more complex space-time structures than plane waves. Here, we show the feasibility of an analytical framework for investigating strong-field QED processes in laser beams of arbitrary space-time structure by determining the energy spectrum of positrons produced via nonlinear Breit-Wheeler pair production as a function of the background field in the realistic assumption that the energy of the incoming photon is the largest dynamical energy in the problem. A numerical evaluation of the angular resolved positron spectrum shows significant quantitative differences with respect to the analogous result in a plane wave, such that the present results will be also important for the design of upcoming strong laser facilities aiming at measuring this process.
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Electron-positron pair plasmas represent a unique state of matter, whereby there exists an intrinsic and complete symmetry between negatively charged (matter) and positively charged (antimatter) particles. These plasmas play a fundamental role in the dynamics of ultra-massive astrophysical objects and are believed to be associated with the emission of ultra-bright gamma-ray bursts. Despite extensive theoretical modelling, our knowledge of this state of matter is still speculative, owing to the extreme difficulty in recreating neutral matter-antimatter plasmas in the laboratory. Here we show that, by using a compact laser-driven setup, ion-free electron-positron plasmas with unique characteristics can be produced. Their charge neutrality (same amount of matter and antimatter), high-density and small divergence finally open up the possibility of studying electron-positron plasmas in controlled laboratory experiments.
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AIM: To determine whether disparities exist in mental health care provision to immigrants and Italian citizens with severe mental illness in Bologna, Italy. METHODS: Records of prevalent cases on 31/12/2010 with severe mental illness and ≥1 contact with Community Mental Health Centers in 2011 were extracted from the mental health information system. Logistic and Poisson regressions were carried out to estimate the probability of receiving rehabilitation, residential or inpatient care, the intensity of outpatient treatments and the duration of hospitalisations and residential care for immigrant patients compared to Italians, adjusting for demographic and clinical covariates. RESULTS: The study population included 8602 Italian and 388 immigrant patients. Immigrants were significantly younger, more likely to be married and living with people other than their original family and had a shorter duration of contact with mental health services. The percentages of patients receiving psychosocial rehabilitation, admitted to hospital wards or to residential facilities were similar between Italians and immigrants. The number of interventions was higher for Italians. Admissions to acute wards or residential facilities were significantly longer for Italians. Moreover, immigrants received significantly more group rehabilitation interventions, while more social support individual interventions were provided to Italians. CONCLUSIONS: The probability of receiving any mental health intervention is similar between immigrants and Italians, but the number of interventions and the duration of admissions are lower for immigrants. Data from mental health information system should be integrated with qualitative data on unmet needs from the immigrants' perspective to inform mental health care programmes and policies.
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We report on the generation of a narrow divergence (θ_{γ}<2.5 mrad), multi-MeV (E_{max}≈18 MeV) and ultrahigh peak brilliance (>1.8×10^{20} photons s^{-1} mm^{-2} mrad^{-2} 0.1% BW) γ-ray beam from the scattering of an ultrarelativistic laser-wakefield accelerated electron beam in the field of a relativistically intense laser (dimensionless amplitude a_{0}≈2). The spectrum of the generated γ-ray beam is measured, with MeV resolution, seamlessly from 6 to 18 MeV, giving clear evidence of the onset of nonlinear relativistic Thomson scattering. To the best of our knowledge, this photon source has the highest peak brilliance in the multi-MeV regime ever reported in the literature.
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BACKGROUND: The Luminex Single-Antigen Beads (LSA) assay allows an accurate detection and characterization of preexisting donor-specific antibodies (DSA) in kidney transplant candidates. But the ability of LSA to detect quite low levels of antibodies makes it hard to correctly predict crossmatch results in donor selection. In this study we retrospectively analyzed the accuracy of our virtual crossmatch (v-XM) protocol, which was used for selection of potential kidney transplant recipients, in predicting the results of actual crossmatch (a-XM) in cadaver-donor renal transplantation. We also investigated correlation between negative a-XM results and strength/specificity of preformed DSA. METHODS: The correlation between negative v-XMs and a-XMs performed in 2007-2012 at the Regional Transplant Center of the Lazio Region, Italy, was analyzed. In carrying out v-XM, the donor HLA molecules against which patients showed LSA-detected DSA with normalized mean fluorescence intensity (MFI)≥5,000 were considered to be "unacceptable DSA," and LSA-DSA showing MFI<5,000 were defined as "acceptable DSA." All cadaver donors had been typed for HLA-A, -B, -DR, and -DQB molecules by sequence-specific primer methods. On the basis of a negative v-XM, we performed 507 a-XMs between serum samples from 256 renal transplant candidates and T/B lymphocytes from 302 cadaver donors with the use of both complement-dependent cytotoxicity (CDC) and flow cytometry (FC) methods. RESULTS: The v-XM negative results showed good correlation with both CDC and FC a-XMs (97% and 90%, respectively). The sensitivity of v-XM was 100%; this high value was related to the lack of false-negative DSA results. The limited specificity with both techniques (CDC-XM, 74%; FC-XM, 79%) was due to the presence of "acceptable" and/or anti-DQA/DPB DSA in some patient sera used to perform the a-XMs. During the study period, 171 (67%) of the 256 sensitized patients received a kidney transplant: 30% of these had "acceptable DSA" and/or anti-DQA/DPB DSA. No antibody-mediated rejection due to preformed HLA-DSA was observed. CONCLUSIONS: Our v-XM protocol showed high sensitivity in predicting donor-recipient immunologic compatibility. The results of this study also demonstrated the importance of evaluating DSA strength for implementing v-XM results in the selection of kidney transplant recipients. Moreover, the finding of anti-DQA/DPB DSA, especially in serum samples that gave positive results with the use of both CDC and FC a-XMs, highlights the importance of defining all of the donor HLA molecules to perform an accurate v-XM.
Subject(s)
Donor Selection , Histocompatibility Testing/methods , Kidney Transplantation , Antibodies/analysis , Female , Flow Cytometry , HLA Antigens/immunology , Humans , Italy , Male , Middle Aged , Retrospective StudiesABSTRACT
The feasibility of obtaining exact analytical results in the realm of QED in the presence of a background electromagnetic field is almost exclusively limited to a few tractable cases, where the Dirac equation in the corresponding background field can be solved analytically. This circumstance has restricted, in particular, the theoretical analysis of QED processes in intense laser fields to within the plane wave approximation even at those high intensities, achievable experimentally only by tightly focusing the laser energy in space. Here, within the Wentzel-Kramers-Brillouin approximation, we construct analytically single-particle electron states in the presence of a background electromagnetic field of general space-time structure in the realistic assumption that the initial energy of the electron is the largest dynamical energy scale in the problem. The relatively compact expression of these states opens, in particular, the possibility of investigating analytically strong-field QED processes in the presence of spatially focused laser beams, which is of particular relevance in view of the upcoming experimental campaigns in this field.
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OBJECTIVE: To characterize the population and short-term outcomes in preterm infants with surgical necrotizing enterocolitis (NEC). STUDY DESIGN: Preterm infants with surgical NEC were identified from 27 hospitals over 3 years using the Children's Hospitals Neonatal Database; infants with gastroschisis, volvulus, major congenital heart disease or surgical NEC that resolved prior to referral were excluded. Patient characteristics and pre-discharge morbidities were stratified by gestational age (<28 vs 28(0/7) to 36(6/7) weeks' gestation). RESULT: Of the 753 eligible infants, 60% were born at <28 weeks' gestation. The median age at referral was 14 days; only 2 infants were inborn. Male gender (61%) was overrepresented, whereas antenatal steroid exposure was low (46%). Although only 11% had NEC totalis, hospital mortality (<28 weeks' gestation: 41%; 28(0/7) to 36(6/7) weeks' gestation: 32%, P=0.02), short bowel syndrome (SBS)/intestinal failure (IF) (20% vs 26%, P=0.06) and the composite of mortality or SBS/IF (50% vs 49%, P=0.7) were prevalent. Also, white matter injury (11.7% vs 6.6%, P=0.02) and grade 3 to 4 intraventricular hemorrhages (23% vs 2.7%, P<0.01) were commonly diagnosed. After referral, the median length of hospitalization was longer for survivors (106 days; interquartile range (IQR) 79, 152) relative to non-survivors (2 days; IQR 1,17; P<0.001). These survivors were prescribed parenteral nutrition infrequently after hospital discharge (<28 weeks': 5.2%; 28(0/7) to 36(6/7) weeks': 9.9%, P=0.048). CONCLUSION: After referral for surgical NEC, the short-term outcomes are grave, particularly for infants born <28 weeks' gestation. Although analyses to predict outcomes are urgently needed, these data suggest that affected infants are at a high risk for lengthy hospitalizations and adverse medical and neuro-developmental abnormalities.