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Staphylococcus aureus is one of the main aetiological agents causing food-borne diseases. Some strains produce enterotoxins responsible for food poisoning. In addition, they can form biofilms on several surfaces such as plastics, glass and stainless steel making it difficult to eliminate them. The present study evaluated, for the first time, the antibacterial and antibiofilm activities of the synthetic compound LMM6 against S. aureus. The minimum inhibitory concentration was 0·97, 1·95 and 1·95 μg ml−1 against S. aureus ATCC 25923, S. aureus 629/94 and S. aureus FRI S-6, respectively. The time-kill curves showed that 96 h treatment with LMM6 reduced approximately 4 log CFU per ml at all tested concentrations. Furthermore, LMM6 reduced S. aureus preformed biofilm by approximately 1 log CFU per cm2. During biofilm formation, a reduction of approximately 4 log CFU per cm2 was observed. LMM6 also reduced biofilm biomass during (~60%) and after biofilm formation (~25 to 45%), as shown by the crystal violet assay. Based on these results, we conclude that LMM6 exhibits antibacterial and antibiofilm activity and may be an innovative synthetic molecule for controlling S. aureus.

We investigate geometric configurations of $\alpha$ ($^4$He nucleus) clusters in the second $J^\pi=2^+$ state of $^{12}$C, which has been discussed as a rotational band member of the second $0^+$ state, the Hoyle state. The ground and excited $0^+$ and $2^+$ states are described by a three-$\alpha$ cluster model. The three-body Schr\"odinger equation with orthogonality conditions is accurately solved by the stochastic variational method with correlated Gaussian basis functions. To analyse the structure of these resonant states in a convenient form, we introduce a confining potential. The two-body density distributions together with the spectroscopic information clarify the structure of these states. We find that main configurations of both the second $0^+$ and $2^+$ states are acute-angled triangle shapes originating from the $^8$Be($0^+$)$+\alpha$ configuration. However, the $^8$Be$+\alpha$ components in the second $2^+$ state become approximately 2/3 because the 8Be subsystem is hard to excite, indicating that the state is not an ideal rigid rotational band member of the Hoyle state., Comment: 7 pages, 3 figures

Enhancement, due to constructive interference through the many possible reaction channels, occurs in two-neutron transfer reactions from a bound system A to a weakly-bound system (A+2), whenever the intermediate system is unbound and consists of a continuum with a resonant state. We elucidate this phenomenon in the case of $^{6}$He, modeled as two neutrons in the orbitals of an intermediate $^{5}$He nucleus, comparing the realistic case of an unbound (A+1) system with an artificially bound case. A properly modeled continuum in these calculations is found to be crucial and leads to significant enhancement due to pairing correlations.

Geometric configurations of three-$\alpha$ particles in the ground- and first-excited $J^\pi=0^+$ states of $^{12}$C are discussed within two types of $\alpha$-cluster models which treat the Pauli principle differently. Though there are some quantitative differences especially in the internal region of the wave functions, equilateral triangle configurations are dominant in the ground state, while in the first excited $0^+$ state isosceles triangle configurations dominate, originating from $^8{\rm Be}+\alpha$ configurations., Comment: 7 pages, 4 figures, contribution to the 8th Asia-Pacific Conference on Few-Body Problems in Physics (APFB2020), 1-5 March 2021, Kanazawa, Japan

Quantum Phase Transitions arising in algebraic and collective models of nuclear structure are reviewed. The concept of quantum phases and phase transitions is described as well as those of critical point symmetries and quasi-dynamical symmetries. Algebraic and collective models are compared and the connections between them are explored. Differences between even–even and odd–even systems are discussed. Several applications of critical point symmetries are given in both the even and odd sectors. Details of the spherical to γ − unstable and spherical to axially deformed quantum shape phase transition are covered in some detail as well as other transitions and alternative approaches.

Bisphosphonates (BPs) are widely used to treat several metabolic and oncological diseases affecting the skeletal system. Despite BPs’ well-known therapeutic potential, they also displayed important side effects, among which is BPs-related osteonecrosis of the jaw, by targeting osteoclast activities, osteoblast, and osteocyte behavior. The aim of this study is to evaluate the biological effects of zoledronic acid (ZOL) in an in vitro model of periodontal ligament stem cells (PDLSCs) by using an experimental setting that resembles the in vivo conditions. PDLSCs were treated with different concentrations of ZOL ranging from 0.1 to 5 μM. The effects of ZOL exposure were evaluated on cell viability via 3-[4,5-Dimethylthiaoly]-2,5-diphenyltetrazolium bromide (MTT), cell cycle analysis, apoptosis detection, and immunofluorescence. Quantitative real-time polymerase chain reaction (PCR), colorimetric detection of alkaline phosphatase activity, and Alizarin Red S staining were performed to investigate the osteogenic potential of PDLSCs exposed to ZOL. MTT analysis showed that the viability of PDLSCs exposed to ZOL concentration ≥1.5 μM for 3 and 6 days was significantly lower (P < 0.001) than that of untreated cells. The percentage of apoptotic cells was significantly higher in PDLSCs exposed for 4 days to ZOL at 2 μM (P < 0.01) and 5 μM (P < 0.001) when compared to the control. Moreover, ZOL treatment (3 days) accounted for alterations in cell cycle distribution, with an increase in the proportion of cells in G0/G1 phase and a reduction in the proportion of cells in S phase. Chronic exposure (longer than 7 days) of PDLSCs to ZOL accounted for the downregulation of ALP, RUNX2, and COL1 genes at all tested concentrations, which fit well with the reduced alkaline phosphatase activity reported after 7 and 14 days of treatment. Reduced Col1 deposition in the extracellular matrix was reported after 14 days of treatment. Increased calcium deposits were observed in treated cells when compared to the control cultures. In conclusion, chronic exposure to 1 μM ZOL induced significant reduction of osteogenic differentiation, while ZOL concentrations ≥1.5 μM are required to impair PDLSCs viability and induce apoptosis.

Densities and transition densities are computed in an equilateral triangular alpha-cluster model for $^{12}$C, in which each $\alpha$ particle is taken as a gaussian density distribution. The ground-state, the symmetric vibration (Hoyle state) and the asymmetric bend vibration are analyzed in a molecular approach and dissected into their components in a series of harmonic functions, revealing their intrinsic structures. The transition densities in the laboratory frame are then used to construct form-factors and to compute DWBA inelastic cross-sections for the $^{12}$C$(\alpha, \alpha')$ reaction. The comparison with experimental data indicates that the simple geometrical model with rotations and vibrations gives a reliable description of reactions where $\alpha$-cluster degrees of freedom are involved.

Our purpose with this paper is mainly to raise the question about the shape of 198Hg and to suggest it as a testing ground for different models. The spectroscopic properties of this nucleus have been investigated by applying a computational code based on the diagonalization the Bohr-Mottelson Hamiltonian with the generalized Gneuss-Greiner potential. The coefficients of the kinetic energy operator and potential energy for this nucleus have been obtained by including the experimental data of some levels in the fitting code. These calculations indicate that the $0^{+}_{2}$ level of nucleus 198Hg is found somewhere between $ 1.23 \lesssim 0^{+}_{2} \lesssim 1.65$ that is precisely the region where a few excited 0+ states are found. Also, they predict a rather rigid triaxial shape around $ \gamma = 30^{\circ}$, that is soft in the $ \beta$ variable.

The structure of $$^{22}$$ C plays a vital role in the new physics at subshell closure of $$N=16$$ in the neutron-rich region. We study the two-neutron correlations in the ground state of the weakly-bound Borromean nucleus $$^{22}$$ C sitting at the edge of the neutron-drip line and its sensitivity to $$\mathrm{core}$$ -n potential. For the present study, we employ a three-body ( $$\mathrm{core}+n+n$$ ) structure model designed for describing the Borromean system by explicit coupling of unbound continuum states of the subsystem ( $$\mathrm{core}+n$$ ). We use a density-independent contact-delta interaction to describe the neutron-neutron interaction and its strength is varied to fix the binding energy. Along with the ground-state properties of $$^{22}$$ C, we investigate its electric-dipole and monopole responses, discussing the contribution of various configurations. Our results indicate more configuration mixing as compared to the previous studies in the ground state of $$^{22}$$ C. However, they strongly depend upon the choice of the $$^{20}\mathrm{C}$$ -n potential as well as the binding energy of $$^{22}$$ C, which call for new precise measurements for the low-lying continuum structure of the binary system ( $$^{20}\mathrm{C}+n$$ ) and the mass of $$^{22}$$ C. These measurements will be essential to understand the Borromean three-body system $$^{22}$$ C with more accuracy.

We explore two-particle transfer reactions as a unique probe of the occurence of shape coexistence in shape phase transitions. The (t,p) reactions to the ground state and to excited $0^+$ states are calculated for the isotope chain of even-even Zirconium isotopes starting from stable nuclei up to beyond current experimental limits. Two-particle spectroscopic factors derived from Monte Carlo Shell Model calculations are used, together with the sequential description of the two-particle transfer reaction mechanism. The calculation shows a clear signature for a shape phase transition between $^{98}$Zr and $^{100}$Zr, which displays coexistence of a deformed ground state with an excited spherical $0^+$ state. Furthermore, we show that there is a qualitative difference with respect to the case of a normal shape phase transition that can be discriminated with two-neutron transfer reactions., Comment: 4 figures, 1 table

Objectives This study is aimed at drawing the profile of the Brazilian general thoracic surgeon. This experience has been fruitful in other areas, helping attract manpower and to better serve the interests of other Societies. This is the first survey of this kind in Brazil and in Latin America. Methods An electronic invitation was sent to the members of the Brazilian Society of Thoracic Surgery to answer a web-based questionnaire and physicians potentially practising thoracic surgery, with 82 questions including demographic data, medical education, training in general and thoracic surgery, continued professional education, practice profile, research activities and certifications, participation in medical societies, income/compensation and career satisfaction. Quantitative and qualitative analyses are presented. Results The estimated level of participation was 82% (468). The mean age of the active general thoracic surgeon is 43.2 (range 45.3±11.4) years. Women comprised 8% (37) of respondents, and 60% (277) of the participants had graduated from public medical schools. Four states nationwide trained 88% (391) of the thoracic surgeons. Only 32% (149) of the surgeons work exclusively with thoracic surgery. The public health system is the main provider of income for thoracic surgeons. Only 11 of 27 states have an adequate, although poorly distributed, number of thoracic surgeons. Conclusions Although Brazil has a reasonable number of general thoracic surgeons, inequalities in their distribution through the country arise as one of the most concerning problems of the speciality. The results of this study show that leadership actions and consistent government policies are required to improve work conditions and provide efficient workforce planning.

Flavonoids are widely distributed secondary metabolites and currently consumed in large amounts in the daily diet. In this article, some of the most recent developments in flavonoid - and related polyphenolic compounds - pharmacology are discussed, with particular emphasis on very recent data, most of which are published in Phytotherapy Research, which highlight new aspects in flavonoid anti-inflammatory, antilipidemic, antihyperglycemic, antiviral, hepatoprotective, gastric antiulcer, cardioprotective, neuroprotective, antioxidant and anticancer actions. These updated data confirm the well-established diverse beneficial pharmacological actions and might support the perspective for a therapeutic use.

The role of different continuum components in the weakly-bound nucleus $^6$He is studied by coupling unbound spd-waves of $^5$He by means of simple pairing contact-delta interaction. The results of our previous investigations in a model space containing only p-waves, showed the collective nature of the ground state and allowed the calculation of the electric quadrupole transitions. We extend this simple model by including also sd-continuum neutron states and we investigate the electric monopole, dipole and octupole response of the system for transitions to the continuum, discussing the contribution of different configurations., Comment: 22 pages, 10 figures

Infrared Search and Track systems are an essential element of the modern and future combat aircrafts. Passive automatic search, detection and tracking functions, are key points for silent operations or jammed tactical scenarios. SKYWARD represents the latest evolution of IRST technology in which high quality electro-optical components, advanced algorithms, efficient hardware and software solutions are harmonically integrated to provide high-end affordable performances. Additionally, the reduction of critical opto-mechanical elements optimises weight and volume and increases the overall reliability. Multiple operative modes dedicated to different situations are available; many options can be selected among multiple or single target tracking, for surveillance or engagement, and imaging, for landing or navigation aid, assuring the maximum system flexibility. The high quality 2D-IR sensor is exploited by multiple parallel processing chains, based on linear and non-linear techniques, to extract the possible targets from background, in different conditions, with false alarm rate control. A widely tested track processor manages a large amount of candidate targets simultaneously and allows discriminating real targets from noise whilst operating with low target to background contrasts. The capability of providing reliable passive range estimation is an additional qualifying element of the system. Particular care has been dedicated to the detector non-uniformities, a possible limiting factor for distant targets detection, as well as to the design of the electro-optics for a harsh airborne environment. The system can be configured for LWIR or MWIR waveband according to the customer operational requirements. An embedded data recorder saves all the necessary images and data for mission debriefing, particularly useful during inflight system integration and tuning.

The phase diagram associated with an algebraic model Hamiltonian that encompasses the main physical ingredients of coupled two-dimensional benders is presented. The model is based on a U ( 3 ) ⊗ U ( 3 ) dynamical algebra and can be applied, for instance, to the study of the bending dynamics of tetratomic molecules. A Hamiltonian with three control parameters, encompassing four dynamical symmetries as limiting cases, is defined and its classical limit is obtained using the intrinsic state formalism. The four possible geometric phases can be associated with linear, cis bent, trans bent, and non-planar configurations. The approach, which is inspired by the dynamics of coupled benders in tetratomic molecular species, is completely general.

A simple three-body model of 6He is extended to include sd-continuum states in the picture in addition to the already investigated p-states. The role of different continuum components in the weakly bound nucleus 6He is studied by coupling unbound spd-waves of 5He by using simple pairing contact-delta interaction. The main focus of this paper is to outline the procedure that allows the calculation of different configurations of 6He including continuum states and to set up basic ingredients for computations. The method and results discussed here will be used for the calculation of monopole, dipole, quadrupole and octupole response of 6He., Comment: 6 pages, 2 figures, presented at XXXIV MAZURIAN LAKES CONFERENCE ON PHYSICS Frontiers in Nuclear Physics, Piaski, Poland, September 6-13, 2015. Acta Physica Polonica B (2016)

International audience; The 12C(18O,16O)14C reaction at 84 MeV incident energy has been explored up to high excitation energy of the residual nucleus thanks to the use of the MAGNEX spectrometer to detect the ejectiles. In the region above the two-neutron separation energy, a resonance has been observed at 16.9 MeV. A multipolarity analysis of the cross section angular distribution indicates an L = 0 character for such a transition.

Developing and implementing a generally accepted procedure for the dating of ink found on documents using dynamic approaches has been a very formidable undertaking by forensic document examiners. 2-Phenoxyethanol (PE), a common volatile organic compound found in ballpoint inks, has been recognized for over a decade as a solvent that evaporates as ink ages. More recently, investigations have focused on the solvent loss ratio of PE prior to and after heating. To determine how often PE occurs in ink formulations, the authors analyzed 633 ballpoint inks utilizing a gas chromatograph/mass spectrometer. 2-Phenoxyethanol was identified in 85% (237/279) and 83% (293/354) of black and blue inks, respectively.

In this manuscript we show our results obtained from undoped QD laser devices grown by Molecular Beam Epitaxy in terms of high modal gain, high characteristic temperature and high frequency behaviour under direct modulation in a wide temperature range. These results were obtained by exploiting heterostructures with InAs quantum dots grown without incorporation of p-doping in the active region or tunnelling injection structures. QD lasers exhibited a saturation modal gain as high as 42 cm(-1), in laser heterostructures containing up to 7-stacked QD layers. Additionally we report on experimental results of directly modulated single-transverse mode QD lasers with 6 layers of QDs, at different temperatures. 10 Gb/s eye patterns at 15 degrees C and 50 degrees C and 5 Gb/s direct modulation in the whole explored temperature range (15 degrees C - 85 degrees C) are demonstrated. A characteristic temperature of I 10 K in the full temperature range was also obtained.

Oscar Wilde was a consumer modernist. His modernist aesthetics drove him into the heart of the mass culture industries of 1890s London, particularly the journalism and popular theatre industries. Wilde was extremely active in these industries: as a journalist at the Pall Mall Gazette; as magazine editor of the Women's World; as commentator on dress and design through both of these; and finally as a fabulously popular playwright. Because of his desire to impact a mass audience, the primary elements of Wilde's consumer aesthetic were superficial ornament and ephemeral public image - both of which he linked to the theatrical. This concern with the surface and with the ephemeral was, ironically, a foundational element of what became twentieth-century modernism - thus we can call Wilde's aesthetic a consumer modernism, a root and branch of modernism that was largely erased.

The ground state and low-lying continuum states of 6He are found within a shell model scheme, in a basis of two-particle states built out of continuum p-states of the unbound 5He nucleus, using a simple pairing contact-delta interaction. This accounts for the Borromean character of the bound ground state, revealing its composition. We investigate the quadrupole response of the system and we put our calculations into perspective with the latest experimental results. The calculated quadrupole strength distribution reproduces the narrow 2+ resonance, while a second wider peak is found at about 3.9 MeV above the g.s. energy., Comment: 5 pages, 5 figures

Flavonoids are widely distributed secondary metabolites and currently consumed in large amounts in the daily diet. In this article, some of the most recent developments in flavonoid - and related polyphenolic compounds - pharmacology are discussed, with particular emphasis on very recent data, most of which are published in Phytotherapy Research, which highlight new aspects in flavonoid anti-inflammatory, antilipidemic, antihyperglycemic, antiviral, hepatoprotective, gastric antiulcer, cardioprotective, neuroprotective, antioxidant and anticancer actions. These updated data confirm the well-established diverse beneficial pharmacological actions and might support the perspective for a therapeutic use.

Infrared Sensors are widely used nowadays on Aircrafts (rotary and fixed wing) to help pilot's activities. The infrared information of the surrounding area are used mainly for two different purposes: Navigation and Search & Track-While-Scan. Navigation functions, commonly identified with the name of Imaging Modes, are devoted to aid pilots in conjunction with advanced human machine interfaces such as Head Up Display (HUD) and Helmet Mounted Display (HMD). The availability of IR images generated from airborne opto- electronics equipment can support the pilot during navigation in adverse weather conditions, providing important information about external threats (i.e. obstacles), otherwise not detectable by human eye. Search & Track-While-Scan, is a functionality related to surveillance. It includes combination of automatic detection and tracking functions within a wide search volume. These features are typically executed in automatic way and generate the position of possible threats present in the flight path. In general Search & Track-While-Scan outputs are not displayed together with the IR image because the main purpose is to provide the estimated positions of the detected targets; nevertheless, if the Imaging Modes and Tracking capabilities are operated simultaneously in an integrated framework, the overall scenario representation can be improved and the situation awareness increased. This paper will focus on the airborne navigation by means of Infrared Sensors by considering the benefits but also possible limits and areas of improvements.

We investigate different aspects connected with shape phase transitions in nuclei and the possible occurrence of dynamical symmetries at the critical points. We discuss in particular the behaviour of the neighbour odd nuclei at the vicinity of the critical points in the even nuclei. We consider both the case of the transition from the vibrational behaviour to the gamma-unstable deformation (characterized within the collective Bohr hamiltonian by the E(5) critical point symmetry) and the case of the transition from the vibrational behaviour to the stable axial deformation (characterized by the X(5) symmetry). The odd particle is assumed to be moving in the three single particle orbitals j=1/2,3/2,5/2, a set of orbitals that is known to lead to possible supersymmetric cases. The coupling of the odd particle to the Bohr hamiltonian does lead in fact in the former case at the critical point to the E(5/12) boson-fermion dynamical symmetry. An alternative approach to the two shape transitions is based on the Interacting Boson Fermion Model. In this case suitably parametrized boson-fermion hamiltonians can describe the evolution of the odd system along the shape transitions. At the critical points both energy spectra and electromagnetic transitions were found to display characteristic patterns similar to those displayed by the even nuclei at the corresponding critical point. The behaviour of the odd nuclei can therefore be seen as necessary complementary signatures of the occurrence of the phase transitions. Ministerio de Ciencia e Innovación FIS2008-04189

We investigate shape phase transitions in odd nuclei within the Interacting Boson Fermion Model. Special attention is given to the case of the transition from the vibrational behaviour to the stable axial deformation. The odd particle is assumed to be moving in the three single particle orbitals j=l/2,3/2,5/2 with a boson-fermion Hamiltonian that leads to the occurrence of the SU^^(3) boson-fermion symmetry when the boson part approaches the SU{3) condition. Both energy spectra and electromagnetic transitions show characteristic patterns similar to those displayed by the even nuclei at the corresponding critical point. The role of the additional particle in characterizing the properties of the critical points in finite quantal systems is investigated by resorting to the formalism based on the intrinsic frame.

The Lie superalgebra u(4|4) is proposed and used to classify cluster states in light nuclei by means of a mass formula based on a particular chain of subalgebras. The building blocks, n,p,d and α particles are the superpartners corresponding to the totally supersymmetric N = 1 IRREP of u(4|4). A number of states of other nuclei (from 5He to 16O) are interpreted as cluster configurations formed by 2 or more building blocks and corresponding to N = 2, 3, ... and their energy is reproduced to a reasonable accuracy. The u(4|4) cluster supersymmetry seems therefore to be approximately realized in nature since it accommodates in a single scheme many nuclear states pertaining to different even and odd isotopes. This furnishes a second important example of supersymmetry in nuclear physics.

We report on the fabrication and characterization of single-transverse mode 1.3 ?m InAs/InGaAs QD lasers in a wide temperature range. Open eye patterns up to 10 Gb/s are reported, whereas a characteristic temperature of about 110 K has been measured in the whole temperature range (15°C - 85°C). These results were obtained by exploiting heterostructures containing six-layers of high modal gain InAs quantum dots grown without incorporation of p-doping. QD lasers exhibited a saturation modal gain as high as 6 cm-1 per QD layer, which linearly increases with the numbers of the quantum dot layers.

The combustion of heavy fuel oil for power generation is a great source of carbonaceous and inorganic particle emissions, even though the combustion technologies and their efficiency are improving. The information about the size distribution function of the particles originated by trace metals present into the fuels is not adequate. In this paper, we focused our attention the influence of emulsion oil-water on the larger distribution mode of both the carbonaceous and metallic particles. Isokinetic sampling was performed at the exhausts of flames of a low-sulphur content heavy oil and its emulsion with water produced in two large pilot plants. The samples were size-segregated by mean of an 8-stages Andersen impactor. Further investigation performed on the samples using electronic microscopy (SEM) coupled with X-ray analysis (EDX) evidenced the presence of solid spherical particles, plerosphere, with typical dimensions ranging between 200 nm and 2-3 mu m, whose atomic composition contains a large amount of the trace metals present in the parent oils (Fe, V, Ni, etc.). EDX analyses revealed that the metal concentration increases as the plerosphere dimension decreases. We also observed that the use of emulsion slightly reduce the emission of fine particles (D-50 < 8 mu m) in the large scale plant.

In order to make determinations of genuineness or counterfeit, it is important for the FDE to have access to the genuine document, or to have sufficient literature about the genuine document and its features in order to make judgments about questioned material. It is also important to recognize and evaluate not only the printing processes used in the construction of the document, but also the security features that are present including any encoded information.

We reviewed 1491 consecutive cases of operated breast cancer between 1999-2004, and found that hormone-dependence, particularly if evaluated with functional markers of the estrogen receptor (estrogen regulated proteins, ERP), is inversely proportional to antigen neu expression. Our data confirms that ERP can give additional information on the probability of response to hormonal therapy.

The axillary lymph node status of patients with newly diagnosed breast cancer remains the most important prognostic information available at the moment. However, only a minority of patients presents with such node metastases at diagnoses. We reviewed our database and studied 500 consecutive patients with early breast cancer, and found that age inferior to 50 years, high grade, diameter superior to 1 cm, elevated Ki-67, and expression of oncogene p-53 are all factors associated with lymph node metastases.

Pelvic exenteration has been described as a formidable procedure in cases of advanced or recurrent pelvic cancers for a variety of primary tumors, including colorectal, gynaecologic and urologic. We report our 14-year experience in a community hospital with 37 cases who underwent pelvic exenteration for recurrent (n = 15) or locally advanced (n = 22) colorectal cancers. At a median follow-up of 36 months, the median survival was 24 and 36 months, respectively, and the 5-year actuarial survival was 18% and 44%.

Sentinel lymph node biopsy allows enhanced pathology through serial sections and immunohistochemical analysis of the retrieved node, with detection of micrometastases and isolated tumor cells not otherwise recognized. We present our experience with a simple, effective, pathology protocol requiring six couples of sections at three different sentinel lymph node levels. Additional micrometastases or ITC were diagnosed in 51/416 patients (14.6%).

503 patients were retrospectively evaluated to assess whether a previous needle or core biopsy, or surgical surgical excision of the primary tumor are associated with passive dislodgment of tumor cells in the sentinel lymph node, as reported in recent publications. We could not identify any increased incidence of sentinel lymph node micrometastases or isolated tumor cells after diagnostic manipulation of the primary tumor.

A theory of light emission in sonoluminescing hydrogen bubbles, based upon transitions in confined atoms, is proposed. Despite the simplicity of the assumptions this model accounts for a number of facts related to sonoluminescence: a broadband spectrum in the correct wavelength window is predicted as well as the number of emitted photons. Taking the temperature at the moment of collapse as a parameter we argue that confined atomic transitions at 4000 K may account for the observed light emission. This result favours a ‘cold’ interpretation of sonoluminescence in contrast to previous theories. Many considerations are qualitatively extendible to rare gases.

Developing and implementing a generally accepted procedure for the dating of ink found on documents using dynamic approaches has been a very formidable undertaking by forensic document examiners. 2-Phenoxyethanol (PE), a common volatile organic compound found in ballpoint inks, has been recognized for over a decade as a solvent that evaporates as ink ages. More recently, investigations have focused on the solvent loss ratio of PE prior to and after heating. To determine how often PE occurs in ink formulations, the authors analyzed 633 ballpoint inks utilizing a gas chromatograph/mass spectrometer. 2-Phenoxyethanol was identified in 85% (237/279) and 83% (293/354) of black and blue inks, respectively.

Thermal transfer printing refers to printing processes that utilize heat to produce an image by either physical or chemical means or by a combination of both. As the technology has improved and the supplies have become less expensive, the use of thermal printing in the personal and business markets has increased significantly. Specifically, dye diffusion thermal transfer and thermal mass transfer have become predominant in the production of counterfeit credit cards, drivers' licenses, and other types of documents produced on plastic media. Chemical analysis by means of thin layer chromatography (TLC) has proven to be useful in characterizing various types of inks (e.g., writing and inkjet inks). In this study, the authors examined 81 different samples that included a total of 54 printer samples (43 photographic prints on paper and eleven plastic card samples) and 27 printer ribbons. A new TLC method was developed and tested utilizing a solvent system (80% n-hexane, 3% methyl ethyl ketone, and 17% ethyl acetate) that is capable of producing excellent resolution.

Intra-operative examination of sentinel LN is controversial. Concordance with definitive exam of SLN in this series was 81%, though only 54% of positive cases were diagnosed. Micrometastases and ITC were usually lost intraoperatively, accounting for 14% of cases. Frozen section and touch prep of the SLN were approximately equivalent. The latter has the advantage of preserving tissue for step-analysis of SLN. The ultimate method of intraoperative analysis of SLN which can combine cost-effectiveness and accuracy needs to be determined.

Immediate breast reconstruction with the transverse rectus abdominis musculocutaneous (TRAM) flap after skin-sparing mastectomy is becoming an increasingly performed procedure in patients with ductal carcinoma in situ, early invasive breast cancer, and prophylactic mastectomy. Through a periareolar approach, it is possible to remove the breast parenchyma along with the nipple areola complex, preserving almost all the original skin envelope and the inframmamary fold. The TRAM flap is used to recreate the volume and shape of the original breast. This technique has higher quality and easier reconstruction. The major disadvantages, extensive scar and donor site skin color mismatch, are reduced to a minimum level because the former is limited at the natural border of the nipple areola and the latter can be effectively concealed with proper nipple reconstruction. Thirty-one patients with a mean age of 39 years (range, 26-50 years) who had undergone unilateral or bilateral mastectomy for early breast cancer and immediate breast reconstruction with the pedicled TRAM flap were retrospectively reviewed. Requirements for the skin-sparing mastectomy technique include suitability of donor site tissue for autologous tissue, early breast cancer or ductal carcinoma in situ, and adequate size and shape matching of the contralateral breast. There was no observed local recur- rence during the follow-up period (mean, 20 months; range, 11-30 months). Complications at the recipient site include mastectomy skin flap partial necrosis in 2 patients and cellulitis of the transferred flap in 1 patient. No total or partial flap necrosis was observed. One patient developed abdominal bulging 1 month after the operation, during the administration of chemotherapy. All reconstruction was considered very satisfactory from an aesthetic perspective by the surgeon and the patient. The nicer aesthetic result with oncological safety is achieved with immediate breast reconstruction with the TRAM flap after skin-sparing mastectomy. The risk of local recurrence is not higher compared with more radical surgical techniques.

Los cincuenta casos de muertes súbitas con sus autopsias, que tengo el honor de presentar a la Facultad y que hemos recogido durante año y medio en la Morgue de esta capital, han sido clasificados en cuatro grupos y un apéndice teniendo en cuenta su físio-patología.