Statistical characterization of residual noise in the low-rank approximation filter framework, general theory and application to hyperpolarized tracer spectroscopy

The use of low-rank approximation filters in the field of NMR is increasing due to their flexibility and effectiveness. Despite their ability to reduce the Mean Square Error between the processed signal and the true signal is well known, the statistical distribution of the residual noise is still undescribed. In this article, we show that low-rank approximation filters are equivalent to linear filters, and we calculate the mean and the covariance matrix of the processed data. We also show how to use this knowledge to build a maximum likelihood estimator, and we test the estimator's performance with a Montecarlo simulation of a 13C pyruvate metabolic tracer. While the article focuses on NMR spectroscopy experiment with hyperpolarized tracer, we also show that the results can be applied to tensorial data (e.g. using HOSVD) or 1D data (e.g. Cadzow filter).Comment: 26 pages, 7 figure

Gravity map of the isla Grande de Tierra de Fuego, and morphology of Lago Fagnano

A complete Bouguer gravity map of the central-eastern part of the Isla Grande de Tierra del Fuego, and a general bathymetric chart of the Lago Fagnano have been realized, on the basis of a series of field geophysical surveys carried out on the Island since 1998. The regional gravity anomaly trend onshore shows a progressive negative gradient from N to S. Distinct, broadly E-W-trending gravity minima are superimposed on this regional negative gradient. They follow the main trace of the Magallanes-Fagnano fault system, which represents the western segment of the left-lateral South America-Scotia transform plate boundary. The gravity minima reflect the presence in the subsurface of restricted and elongated basins developed within the principal displacement zone of the fault system. A relative positive gravity maximum is located just at the SE corner of the Lago Fagnano, and represents the response of a partially exposed crystalline body, occupying an area 3 x 3 km wide. A 2D vertical crustal model has been constructed, combining gravity data inversion and geological information available for the central-eastern region of Lago Fagnano. The bathymetric map of the Lago Fagnano delineates the main morphological features of this 110-km-long, 7-km-wide lake, the largest of Isla Grande. The floor is divided into distinct parts, which suggests that the basin is composed of different sub-basins. In most areas, the basin floor is highly asymmetric in shape, with flat depocentral areas. The most pronounced asymmetry of the basin is seen in the eastern end of the lake, where there is also the deepest depression. The steeper slope of the basin, along the northern shore of the Lago Fagnano, also coincides with the most pronounced regional topographic gradient. The general gravimetric and morphological features of the investigated region are here discussed

Rapid detection of intestinal carriage of Klebsiella pneumoniae producing KPC carbapenemase during an outbreak

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Analysis of Risk Factors Associated With Asymptomatic Colonization of Methicillin Resistant Staphylococcus aureus (MRSA) Among Community College Students

The bacterium Staphylococcus aureus has been an important human ailment for centuries, and with the overuse of antibiotics, methicillin resistant Staphylococcus aureus (MRSA) has emerged as a deadly, costly pathogen worldwide. Healthy carriers can become sick or can spread MRSA without symptoms. The amount of asymptomatic colonization among healthy college students and risk factors for colonization by MRSA are not well understood. According to the epidemiologic triangle model, the host (students who take antibiotics or have a history of skin infections), the infectious agent (MRSA) and the environment (direct contact with people, animals, or objects that may harbor MRSA) all play an important role in this disease. This study explored MRSA colonization rates among healthy students at a community college and explored the possibility that students exposed to sources of MRSA might have a higher colonization rate. Using a cross-sectional quantitative design with stratified sampling, risk factors to include student\u27s discipline, gender, race, work, and leisure exposure were surveyed. In tandem, Mannitol Salt Agar and MRSA Select Agar were inoculated from nasal swabs to identify students colonized by MRSA. The data were analyzed using contingency tables and Chi Squares. Significant risk factors identified included students who had a major that involved touching shared equipment and/or those who were in majors such as nursing, students who had close contact with animals, and students who had a skin infection. The implication for positive social change include improved awareness of MRSA colonization and risk factors which can lead to better prevention strategies and increased awareness among the student population

Diabetes and acute bacterial skin and skin structure infections.

Acute bacterial skin and skin structures infections (ABSSSIs) are associated with high morbidity, costs and mortality in patients with diabetes mellitus. Their appropriate management should include several figures and a well-organized approach. This review aims to highlight the interplay between diabetes and ABSSSIs and bring out the unmet clinical needs in this area. Pathogenetic mechanisms underlying the increased risk of ABSSSIs in diabetes mellitus are multifactorial: high glucose levels play a crucial pathogenetic role in the tissue damage and delayed clinical cure. Moreover, the presence of diabetes complications (neuropathy, vasculopathy) further complicates the management of ABSSSIs in patients with diabetes. Multidrug resistance organisms should be considered in this population based on patient risk factors and local epidemiology and etiological diagnosis should be obtained whenever possible. Moreover, drug-drug interactions and drug-related adverse events (such as nephrotoxicity) should be considered in the choice of antibiotic therapy. Reducing unnecessary hospitalizations and prolonged length of hospital stay is of primary importance now, more than ever. To achieve these objectives, a better knowledge of the interplay between acute and chronic hyperglycemia, multidrug resistant etiology, and short and long-term outcome is needed. Of importance, a multidisciplinary approach is crucial to achieve full recovery of these patients

Carbapenem-Sparing Antibiotic Regimens for Infections Caused by Klebsiella pneumoniae Carbapenemase-Producing K. pneumoniae in Intensive Care Unit

A carbapenem-sparing regimen of tigecycline plus gentamicin or colistin was effective for treating 24 of 26 (92%) Klebsiella pneumoniae carbapenemase-producing K. pneumoniae infectious episodes in 22 polytrauma intensive care unit patients without comorbidities. The 30-day crude mortality rate was 14%. Regimens were considered appropriate in 12% of episodes according to the Vitek 2 System and in 100% based on E-test

Seismostratigraphic and structural setting of the Malvinas Basin and its southern margin (Tierra del fuego Atlantic offshore)

New multichannel seismic reflection profiles acquired off the Tierra del Fuego Atlantic margin, from the southern part of the Malvinas foreland basin to the inner sector of the Magallanes fold and thrust belt, combined with available commercial profiles and exploration wells, allowed to outline the sedimentary architecture of the foreland basin and the structure of its deformed southern margin. Five major unconformities were differentiated within the sedimentary fill of the southern Malvinas basin, which neighbours the offshore extension of the Magallanes basin in Tierra del Fuego. The unconformity-bounded units record the corresponding major evolutionary tectonostratigraphic phases of the southern part of the Malvinas basin, and the development of the Magallanes fold-and thrust belt during Mesozoic and Cenozoic times: Unit 1 - Pre-Jurassic basement; Unit 2 - Rift phase (Middle - Upper Jurassic); Unit 3 - Sag phase (Lower – Upper Cretaceous); Unit 4 – Foredeep transitional phase (Upper Cretaceous - Middle Eocene); Unit 5 - Foreland phase (Middle Eocene - Pleistocene). The southern edge of the Malvinas basin corresponds to the imbricate basement wedges of the Fuegian Cordillera, which shows a thick-skin structural style developed as a consequence of the Middle Tertiary Andean compressional tectonic phase. Large folds, with low angle NE-verging thrusts propagated the shortening basin-ward at shallow structural levels. These structures are superimposed by an array of left-lateral strike-slip lineaments pertaining to the EW trending Magallanes-Fagnano fault system. In the Tierra del Fuego region these structures represent the western segment of the South America – Scotia plate boundary. Several Neogene pull-apart basins were formed along the principal deformation zone in correspondence of step-overs and releasing bends. These basins show an evident asymmetry in the sedimentary architecture, and are bounded by sub-vertical faults that in some cases reach the sea-floor. Other transtensional features were also recognized in the inner sector of the fold-and-thrust belt together with the formation of restricted pull-apart basins

Quercetin loaded gelatin films with modulated release and tailored anti-oxidant, mechanical and swelling properties

Quercetin, a flavonoid widely diffused in fruits and vegetables, is known for its good pharmacological qualities, such as anti-oxidant and anti-inflammatory properties. In this work, we loaded quercetin on gelatin films with the aim to develop materials with tailored anti-oxidant, mechanical and stability properties. To this purpose, gelatin films at increasing flavonoid content were prepared using two different solvents, namely H2O/EtOH (EtOH films) and DMSO (DMSO films). Quercetin content increased up to about 3.8 and 1.8 wt% in DMSO and EtOH films, respectively. The use of DMSO as solvent prevents the partial regain of collagen triple helix structure during gelling of gelatin sols and results in remarkable extensibility of the films. At variance, EtOH films display X-ray diffraction patterns and DSC plots in agreement with the presence of triple helix structure, and exhibit reduced swelling and increasing mechanical properties on increasing quercetin content. Moreover, their values of denaturation enthalpy indicate the presence of chemical interaction between the flavonoid and gelatin, which can be responsible of their lower quercetin release in PBS in comparison to DMSO films. The flavonoid release is sustained for both series of films and occurs through anchorage to gelatin nanoparticles. Moreover, both DMSO and EtOH functionalized films exhibit relevant anti-oxidant properties, in agreement with their RSA levels, which are comparable to that of pure quercetin

Meropenem-Vaborbactam as Salvage Therapy for Ceftazidime-Avibactam-, Cefiderocol-Resistant ST-512 Klebsiella pneumoniae-Producing KPC-31, a D179Y Variant of KPC-3

A 68-year-old man had recurrent bacteremia by Klebsiella pneumoniae carbapenemase (KPC)-producing K. pneumoniae resistant to ceftazidime-avibactam and cefiderocol. The sequencing of a target region showed that it harbored a KPC-3 variant enzyme (D179Y; KPC-31), which confers resistance to ceftazidime-avibactam and restores meropenem susceptibility. The patient was successfully treated with meropenem-vaborbactam