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In this note we study estimates from below of the single radius spherical discrepancy in the setting of compact two-point homogeneous spaces. Namely, given a d-dimensional manifold M endowed with a distance ρ so that (M , ρ) is a two-point homogeneous space and with the Riemannian measure μ , we provide conditions on r such that if D r denotes the discrepancy of the ball of radius r, then, for an absolute constant C > 0 and for every set of points { x j } j = 1 N , one has ∫ M | D r (x) | 2 d μ (x) ⩾ C N - 1 - 1 d . The conditions on r that we have depend on the dimension d of the manifold and cannot be achieved when d ≡ 1 (mod 4) . Nonetheless, we prove a weaker estimate for such dimensions as well. [ABSTRACT FROM AUTHOR]

Natural and anthropogenic gas radionuclides such as radon, xenon, hydrogen and krypton isotopes must be monitored to be managed as pathogenic agents, radioactive diagnostic agents or nuclear activity indicators. State-of-the-art detectors based on liquid scintillators suffer from laborious preparation and limited solubility for gases, which affect the accuracy of the measurements. The actual challenge is to find solid scintillating materials simultaneously capable of concentrating radioactive gases and efficiently producing visible light revealed with high sensitivity. The high porosity, combined with the use of scintillating building blocks in metal–organic frameworks (MOFs), offers the possibility to satisfy these requisites. We demonstrate the capability of a hafnium-based MOF incorporating dicarboxy-9,10-diphenylanthracene as a scintillating conjugated ligand to detect gas radionuclides. Metal–organic frameworks show fast scintillation, a fluorescence yield of ∼40%, and accessible porosity suitable for hosting noble gas atoms and ions. Adsorption and detection of 85Kr, 222Rn and 3H radionuclides are explored through a newly developed device that is based on a time coincidence technique. Metal–organic framework crystalline powder demonstrated an improved sensitivity, showing a linear response down to a radioactivity value below 1 kBq m−3 for 85Kr, which outperforms commercial devices. These results support the possible use of scintillating porous MOFs to fabricate sensitive detectors of natural and anthropogenic radionuclides. Detection of gas radionuclides is limited in sensitivity with present methods, but may be useful in energy, security, medical and other sectors. In this work, gas-concentrating porous scintillating metal–organic frameworks are demonstrated for gas radionuclide detection. [ABSTRACT FROM AUTHOR]

In this work, we consider smooth unbounded worm domains Z λ in C 2 and show that the Bergman projection, densely defined on the Sobolev spaces H s , p (Z λ) , p ∈ (1 , ∞) , s ≥ 0 , does not extend to a bounded operator P λ : H s , p (Z λ) → H s , p (Z λ) when s > 0 or p ≠ 2. The same irregularity was known in the case of the non-smooth unbounded worm. This improved result shows that the irregularity of the projection is not a consequence of the irregularity of the boundary but instead of the infinite windings of the worm domain. [ABSTRACT FROM AUTHOR]

We provide a multidimensional weighted Euler–MacLaurin summation formula on polytopes and a multidimensional generalization of a result due to L. J. Mordell on the series expansion in Bernoulli polynomials. These results are consequences of a more general series expansion; namely, if χ τ P denotes the characteristic function of a dilated integer convex polytope P and q is a function with suitable regularity, we prove that the periodization of q χ τ P admits an expansion in terms of multivariate Bernoulli polynomials. These multivariate polynomials are related to the Lerch Zeta function. In order to prove our results we need to carefully study the asymptotic expansion of q χ τ P ^ , the Fourier transform of q χ τ P . [ABSTRACT FROM AUTHOR]

In this work,we explore the theme of L p -boundedness of Bergman projections of domains that can be covered, in the sense of ramified coverings, by "nice" domains (e.g., strictly pseudoconvex domains with real analytic boundary). In particular, we focus on two-dimensional normal ramified coverings whose covering group is a finite unitary reflection group. In an infinite family of examples, we are able to prove L p -boundedness of the Bergman projection for every p ∈ (1 , ∞) . [ABSTRACT FROM AUTHOR]

Large Stokes shift fast emitters show a negligible reabsorption of their luminescence, a feature highly desirable for several applications such as fluorescence imaging, solar-light managing, and fabricating sensitive scintillating detectors for medical imaging and high-rate high-energy physics experiments. Here we obtain high efficiency luminescence with significant Stokes shift by exploiting fluorescent conjugated acene building blocks arranged in nanocrystals. Two ligands of equal molecular length and connectivity, yet complementary electronic properties, are co-assembled by zirconium oxy-hydroxy clusters, generating crystalline hetero-ligand metal-organic framework (MOF) nanocrystals. The diffusion of singlet excitons within the MOF and the matching of ligands absorption and emission properties enables an ultrafast activation of the low energy emission in the 100 ps time scale. The hybrid nanocrystals show a fluorescence quantum efficiency of ~60% and a Stokes shift as large as 750 meV (~6000 cm−1), which suppresses the emission reabsorption also in bulk devices. The fabricated prototypal nanocomposite fast scintillator shows benchmark performances which compete with those of some inorganic and organic commercial systems. The development of highly luminescent materials such as large Stokes shift fast emitters is desirable for their potential application in photonics. Here the authors engineer hetero-ligand metal-organic frameworks nanoparticles to achieve high emission yield, large Stokes shift and realize a prototypal fast scintillator. [ABSTRACT FROM AUTHOR]

The photon upconversion based on triplet–triplet annihilation (TTA) is a mechanism that converts the absorbed low-energy electromagnetic radiation into higher energy photons also at extremely low excitation intensities, but its use in actual technologies is still hindered by the limited availability of efficient annihilator moieties. We present here the results obtained by the synthesis and application of two new fluorinated chromophores based on phenazine and acridine structures, respectively. Both compounds show upconverted emission demonstrating their ability as TTA annihilator. More interesting, the acridine-based chromophore shows an excellent TTA yield that overcomes the one of some of best model systems. By correlating the experimental data and the quantum mechanical modeling of the investigated compound, we propose an alternative efficient pathway for the generation of the upconverted emissive states involving the peculiar high-energy triplet levels of the dye, thus suggesting a new development strategy for TTA annihilators based on the fine tuning of their high-energy excited states properties. [ABSTRACT FROM AUTHOR]

Background and aims: Little is known about the outcome predictors in peripheral neuropathy (PN). This prospective observational study aimed to identify possible factors predicting the functional abilities in older patients with PN undergoing motor rehabilitation. Methods: Data were collected in 80 PN patients, aged over 65 years, performing a standard inpatient motor rehabilitation program. The total Functional Independence Measure (FIM) score after rehabilitation, as well as efficiency and effectiveness in total-FIM, were the outcome measures. Backward multiple regression analyses identified the predictors of functional status. Results: At the end of rehabilitation, total-FIM score was 102.66 ± 10.75, efficiency in total-FIM 0.64 ± 0.29 and effectiveness in total-FIM 48.81 ± 15.35%. Katz index at admission was a predictor of the final total-FIM score (beta 0.46, p < 0.001) and efficiency in total-FIM (beta − 0.38, p = 0.001). Conversely, age was a predictor of the final total-FIM score (beta − 0.31, p = 0.002) and effectiveness in total-FIM (beta − 0.49, p < 0.001). The R2 values of the models were, respectively, 0.39, 0.15, and 0.24. Discussion: In PN patients, functional impairment at admission and age are important predictors of functional abilities at the end of rehabilitation. Conclusions: These findings suggest the need for more intensive rehabilitation in older, more disabled PN patients because they risk achieving lower functional levels with standard rehabilitation programs. [ABSTRACT FROM AUTHOR]

In this work we study what we call Siegel–dissipative vector of commuting operators (A 1 , ... , A d + 1) on a Hilbert space H and we obtain a von Neumann type inequality which involves the Drury–Arveson space DA on the Siegel upper half-space U . The operator A d + 1 is allowed to be unbounded and it is the infinitesimal generator of a contraction semigroup { e - i τ A d + 1 } τ < 0 . We then study the operator e - i τ A d + 1 A α where A α = A 1 α 1 ⋯ A d α d for α ∈ N 0 d and prove that can be studied by means of model operators on a weighted L 2 space. To prove our results we obtain a Paley–Wiener type theorem for DA and we investigate some multiplier operators on DA as well. [ABSTRACT FROM AUTHOR]

We introduce and study a family of spaces of entire functions in one variable that generalise the classical Paley–Wiener and Bernstein spaces. Namely, we consider entire functions of exponential type a whose restriction to the real line belongs to the homogeneous Sobolev space W ˙ s , p and we call these spaces fractional Paley–Wiener if p = 2 and fractional Bernstein spaces if p ∈ (1 , ∞) , that we denote by P W a s and B a s , p , respectively. For these spaces we provide a Paley–Wiener type characterization, we remark some facts about the sampling problem in the Hilbert setting and prove generalizations of the classical Bernstein and Plancherel–Pólya inequalities. We conclude by discussing a number of open questions. [ABSTRACT FROM AUTHOR]

Scintillators, materials that produce light pulses upon interaction with ionizing radiation, are widely employed in radiation detectors. In advanced medical-imaging technologies, fast scintillators enabling a time resolution of tens of picoseconds are required to achieve high-resolution imaging at the millimetre length scale. Here we demonstrate that composite materials based on fluorescent metal–organic framework (MOF) nanocrystals can work as fast scintillators. We present a prototype scintillator fabricated by embedding MOF nanocrystals in a polymer. The MOF comprises zirconium oxo-hydroxy clusters, high-Z linking nodes interacting with the ionizing radiation, arranged in an orderly fashion at a nanometric distance from 9,10-diphenylanthracene ligand emitters. Their incorporation in the framework enables fast sensitization of the ligand fluorescence, thus avoiding issues typically arising from the intimate mixing of complementary elements. This proof-of-concept prototype device shows an ultrafast scintillation rise time of ~50 ps, thus supporting the development of new scintillators based on engineered fluorescent MOF nanocrystals. Composites of fluorescent metal–organic framework nanocrystals in a polymer are exploited to create fast scintillators with a rise time of about 50 ps. [ABSTRACT FROM AUTHOR]

Key Summary Points: Aim: The aim of study was to identify factors predicting balance in older hip fracture patients undergoing motor rehabilitation.The aim of study was to identify factors predicting balance in older hip fracture patients undergoing motor rehabilitation. Findings: Cognitive function, comorbidity and hip muscles strength are important predictors of balance in hip fracture patients. Message: Knowledge of specific predictors could be useful for physicians to identify patients needing specific rehabilitation programs for balance. Purpose: Little is known about the factors predicting balance in hip fracture patients. The aim of this retrospective observational study was to assess balance before and after inpatient rehabilitation and, secondarily, to identify factors predicting the balance levels in older hip fracture patients after motor rehabilitation. Methods: Data were collected in 124 hip fracture patients over a 2-year period. All patients underwent a standard motor rehabilitation program. A modified version of Berg Balance Scale (BBS) score after rehabilitation, daily gain and percentage of improvement in BBS were the outcome measures. Multivariate regression analysis was performed to identify the predictors of balance. Results: The mean BBS score was 8.33 ± 7.23 at admission and 21.79 ± 12.15 at the end of rehabilitation (p < 0.001). The daily gain in BBS score was 0.39 ± 0.31 and the percent improvement was 32.28 ± 23.04%. Standing with one foot in front and standing on one foot were the BBS items with the lowest score at discharge and the lowest daily gain and percent improvement. The Cognitive-Functional Independence Measure (cognitive-FIM), hip muscles strength, and Katz index at discharge had moderate-to-strong relationships with final score, daily gain and percentage of improvement in BBS. Cognitive-FIM was a predictor of final BBS score (beta 0.49, p < 0.001), daily gain in BBS (beta 0.34, p < 0.001) and percent improvement in BBS (beta 0.44, p < 0.001). Conversely, hip muscles strength was a predictor of final BBS score (beta 0.32, p = 0.001), and Cumulative Illness Rating Scale severity, a predictor of daily gain in BBS (beta -0.29, p = 0.001). The R2 value of the models were, respectively, 0.39, 0.23, and 0.19. Conclusions: Cognitive function, comorbidities and hip muscles strength are important predictors of balance in hip fracture patients. Knowledge of these specific factors can be useful for physicians to identify patients needing specific rehabilitation programs for balance. [ABSTRACT FROM AUTHOR]

We study the fractional Laplacian and the homogeneous Sobolev spaces on R d , by considering two definitions that are both considered classical. We compare these different definitions, and show how they are related by providing an explicit correspondence between these two spaces, and show that they admit the same representation. Along the way, we also prove some properties of the fractional Laplacian. [ABSTRACT FROM AUTHOR]

Background: The role of microRNAs (miRNAs) in celiac disease (CD) is unclear.Aims: We evaluated inflammation-related miRNA-146a, miRNA-155, miRNA-21, and miRNA-125b expression in peripheral blood and intestinal mucosa of CD adults.Methods: Thirty patients with CD were included: patients with active CD on a gluten-containing diet (CD-active, n = 10), patients on a gluten-free diet (for at least 1 year), and patients with negative blood antibodies (CD-inactivePE, n = 10). In addition, ten healthy volunteers formed the comparison/control group. MiRNA expression was measured in duodenal biopsies from patients (CD-inactiveMU, n = 10) after in vitro exposure to PT gliadin and 33-mer peptide. MiRNAs expression was measured in plasma and in peripheral blood mononuclear cells (PBMCs) and monocytes, before and after in vitro exposure to native gliadin (gliadinN).Results: Expression levels of miRNA-146a, miRNA-155, and miRNA-21 in PBMCs, miRNA-155 in monocytes and miRNA-155, miRNA-21, and miRNA-125b in plasma were elevated in both groups of celiac patients. After in vitro exposure with gliadinN, miRNA-146a and miRNA-155 expression markedly increased in PBMCs and monocytes, while miRNA-155 and miRNA-21 increased in the CD-active group. MiRNAs expression in intestinal mucosa did not change. MiRNA-146a and miRNA-155 expression showed high sensitivity and specificity for the presence of CD, irrespective of the current dietary treatment.Conclusions: Selected inflammation-related miRNAs expression is elevated in the peripheral blood of celiac. This suggests their participation in the immune processes underlying the pathology. Their similar response in active and inactive CD suggests that they should be further evaluated, as potential diagnostic biomarkers for CD. [ABSTRACT FROM AUTHOR]

Background and aim: The aim of this prospective observational cohort study was to verify the relationship between number of drugs used and functional outcome in hip fracture patients undergoing rehabilitation. Methods: This study was conducted on 139 patients with hip fracture who underwent a rehabilitation program. Efficiency rate in the Functional Independence Measure (FIM) and Berg Balance Scale (BBS), and length of stay (LOS) were the outcome measures. Results: At the end of rehabilitation, 66.1% of patients showed an increase in number of drugs used, while 33.9% used the same or lower number of drugs than at admission. At the end of rehabilitation patients with increased pharmacotherapy took a higher total number of drug classes (p = 0.001), had longer LOS (p = 0.009) and lower Berg efficiency (p = 0.048) than patients with the same or lower pharmacotherapy. The number of drugs used at discharge was an independent determinant of LOS (beta = 0.19, p = 0.022) and FIM efficiency (beta = − 0.20, p = 0.025). Age was a determinant of LOS (beta = 0.17, p = 0.044) and BBS efficiency (beta = − 0.23, p = 0.009), while CIRS severity was a determinant of BBS efficiency only (beta = − 0.22, p = 0.016). Discussion: Findings of study indicate that in hip fracture patients, the number of drugs prescribed at discharge is an important indicator of LOS and rehabilitation efficiency. Conclusions: These findings can help the physician to better plan the rehabilitation of hip fracture patients who require polypharmacy. [ABSTRACT FROM AUTHOR]

In this paper we study spaces of holomorphic functions on the Siegel upper half-space U and prove Paley–Wiener type theorems for such spaces. The boundary of U can be identified with the Heisenberg group H n . Using the group Fourier transform on H n , Ogden and Vagi (Adv Math 33(1):31–92, 1979) proved a Paley–Wiener theorem for the Hardy space H 2 (U) . We consider a scale of Hilbert spaces on U that includes the Hardy space, the weighted Bergman spaces, the weighted Dirichlet spaces, and in particular the Drury–Arveson space, and the Dirichlet space D . For each of these spaces, we prove a Paley–Wiener theorem, some structure theorems, and provide some applications. In particular we prove that the norm of the Dirichlet space modulo constants D ˙ is the unique Hilbert space norm that is invariant under the action of the group of automorphisms of U . [ABSTRACT FROM AUTHOR]

Background and aims: Executed studies did not clearly identify which index of comorbidity was an independent outcome determinant. The aim of this prospective observational cohort study was to address this issue.Methods: We analyzed 200 consecutive patients with hip fracture. All patients underwent rehabilitation. At admission comorbidity was assessed through the cumulative severity, severity index, and comorbidity index of the Cumulative Illness Rating Scale. Discharge scores and effectiveness in the Functional Independence Measure motor subscale, and discharge destination were the outcome measures. Multivariate regression analyses were performed to identify determinants of outcome.Results: Mini Mental State Examination and comorbidity index of the Cumulative Illness Rating Scale were important independent determinants of final (respectively, β = 0.46 and −0.25) and effectiveness (respectively, β = 0.47 and −0.25) in motor Functional Independence Measure scores, while hip strength and Rankin score were determinants of final motor Functional Independence Measure score (respectively, β = 0.21 and −0.20). Comorbidity index of the Cumulative Illness Rating Scale (odds ratio 8.18 for ≥3 versus < 3 comorbidity score; 95% confidence interval, 1.03-64.7) and Geriatric Depression Scale (odds ratio 4.02 for ≥6 versus ≤5 depression scale score; 95% confidence interval, 1.52-10.63) were risk indicators for nursing home.Conclusions: Among the indices of the Cumulative Illness Rating Scale, comorbidity index is the sole independent determinant of both motor Functional Independence Measure scores and discharge destination in hip fracture patients. This suggests to specifically evaluate this index to identify the patients who may be admitted to a rehabilitation program. [ABSTRACT FROM AUTHOR]

In this paper we study the regularity of the Szegő projection on Lebesgue and Sobolev spaces on the distinguished boundary of the unbounded model worm domain $$D_\beta $$ . We denote by $$d_b(D_\beta )$$ the distinguished boundary of $$D_\beta $$ and define the corresponding Hardy space $${\mathscr {H}}^2(D_\beta )$$ . This can be identified with a closed subspace of $$L^2(d_b(D_\beta ),d\sigma )$$ , that we denote by $${\mathscr {H}}^2(d_b(D_\beta ))$$ , where $$d\sigma $$ is the naturally induced measure on $$d_b(D_\beta )$$ . The orthogonal Hilbert space projection $${\mathscr {P}}: L^2(d_b(D_\beta ), d\sigma )\rightarrow {\mathscr {H}}^2(d_b(D_\beta ))$$ is called the Szegő projection on the distinguished boundary. We prove that $${\mathscr {P}}$$ , initially defined on the dense subspace $$L^2\cap L^p(d_b( D_\beta ),d\sigma )$$ extends to a bounded operator $${\mathscr {P}}: L^p(d_b(D_\beta ), d\sigma )\rightarrow L^p(d_b(D_\beta ), d\sigma )$$ if and only if $$\textstyle {\frac{2}{1+\nu _\beta }}\pi $$ . Furthermore, we also prove that $${\mathscr {P}}$$ defines a bounded operator $${\mathscr {P}}: W^{s,2}(d_b(D_\beta ),d\sigma )\rightarrow W^{s,2}(d_b(D_\beta ), d\sigma )$$ if and only if $$0\le s<\textstyle {\frac{\nu _\beta }{2}}$$ where $$W^{s.2}(d_b( D_\beta ), d\sigma )$$ denotes the Sobolev space of order s and underlying $$L^2$$ -norm. Finally, we prove a necessary condition for the boundedness of $${\mathscr {P}}$$ on $$W^{s,p}(d_b(D_\beta ), d\sigma )$$ , $$p\in (1,\infty )$$ , the Sobolev space of order s and underlying $$L^p$$ -norm. [ABSTRACT FROM AUTHOR]

In this work we provide an asymptotic expansion for the Szegö kernel associated to a suitably defined Hardy space on the non-smooth worm domain $$D'_{\upbeta }$$ . After describing the singularities of the kernel, we compare it with an asymptotic expansion of the Bergman kernel. In particular, we show that the Bergman kernel has the same singularities of the first derivative of the Szegö kernel with respect to any of the variables. On the side, we prove the boundedness of the Bergman projection operator on Sobolev spaces of integer order. [ABSTRACT FROM AUTHOR]

The conversion of low-energy light into photons of higher energy based on sensitized triplet-triplet annihilation upconversion (TTA-UC) has emerged as a promising wavelength-shifting methodology because it permits UC at excitation powers as low as the solar irradiance. However, its application has been significantly hampered by the slow diffusion of excited molecules in solid matrices. Here, we introduce metal-organic frameworks (MOFs) that promote TTA-UC by taking advantage of triplet exciton migration among fluorophores that are regularly aligned with spatially controlled chromophore orientations. We synthesized anthracene-containing MOFs with different molecular orientations, and the analysis of TTA-UC emission kinetics unveiled a high triplet diffusion rate with a micrometre-scale diffusion length. Surface modification of MOF nanocrystals with donor molecules and their encapsulation in glassy poly(methyl methacrylate) (PMMA) allowed the construction of molecular-diffusion-free solid-state upconverters, which lead to an unprecedented maximization of overall UC quantum yield at excitation powers comparable to or well below the solar irradiance. [ABSTRACT FROM AUTHOR]

The aim of this study was to evaluate the correlation between the changes of SUV and of apparent diffusion coefficient (ADC) before and after neoadjuvant therapy, to enable us predict the therapy response, in patients with locally advanced rectal cancer (LARC). A total of 30 patients with LARC who underwent CRT were recruited for our study. All the patients underwent a whole body 18F-FDG-PET/CT scan and a pelvic MR examination including DW imaging for staging (PET/CT1 and RM1), and after the chemoradiation therapy (PET/CT2, and RM2). Histopathologic analysis of rectal specimen, according to tumor regression grade (Mandard's criteria) was used as the standard reference. MR and PET-CT images were analyzed, and measurements of ADC values and SUV were taken. Diagnostic performance for selection of complete responders (TRG1-2) and overall diagnostic accuracy for each item were calculated. After neoadjuvant therapy, all patients were submitted to surgery. According to Mandard's criteria, 21 tumors showed complete (TRG1) or subtotal regression (TRG2) and were classified as responders; nine tumors were classified as non responders (TRG3, 4, and 5). In all the patients, mean value of SUV in PET/CT1 was higher than those in PET/CT2 ( P < 0.001), whereas mean ADC value was lower in RM1 than RM2 ( P < 0.001), with a significant percentage decrease of values after the treatment ( P < 0.005).The best predictors cut-off values for TRG response were SUV of 4.4 and ADC of 1.28 × 10 mm/s with sensitivity, specificity accuracy, negative predictive value, and positive predictive values of 77.3%, 88.9%, 80.7%, 61.5%, and 94.4%, respectively. We conclude from the overall data of this study that the absolute values of SUV and ADC of rectal lesion after CRT were the best parameters to define the response to treatment, by differentiating fibrosis from viable tumor tissue. [ABSTRACT FROM AUTHOR]

Novel photoluminescent materials formed by some selected surfactants, metal derivatives of bis(2-ethylhexyl) sulfosuccinate (M(AOT); M = Na, Co, Er and Yb), bis(2-ethylhexyl) amine (BEEA), bis(2-ethylhexy1) phosphoric acid (HDEHP) and a 1:1 BEEA/HDEHP mixture, doped with the red perylimide (ROT-300) have been prepared, and their optical properties have been tested by absorption spectroscopy and steady state and time-resolved fluorescence. Experimental results show spectral shifts of the typical ROT-300 absorption and fluorescence bands with respect to that in apolar solvent medium. Data analysis leads consistently to attribute this feature mainly to the freezing of the diffusive movement of the dye molecules confined in the nanodomains of the surfactant liquid crystals, whilst minor effects can be due to interaction with the surfactant polar groups. Potentialities of these novel luminescent nanostructured composites as dye lasers, optical amplifiers and solar concentrators have been highlighted. In particular, under optical pumping using a pulse laser, amplified spontaneous fluorescence emission of the ROT-300/HDEHP system above an excitation energy threshold value of about 725 mJ cm was observed. [ABSTRACT FROM AUTHOR]

Background: Few reports have elucidated the role of minimally invasive surgery (MIS) for pediatric malignancies. This study aimed to review the results of a multicenter study on the management of thoracic tumors in children using MIS.Methods: A 5-year retrospective review of all MIS procedures for the treatment of pediatric malignancies performed in seven centers belonging to the Italian Society of Videosurgey in Infancy is reported. The data from 145 pediatric oncologic patients (80 girls and 65 boys) ages 30 days to 17 years (median, 7.2 years) were analyzed. Of the procedures performed, 87 were laparoscopies (60%), 55 were thoracoscopies (38%), and 3 were lumboscopies (2%). This study focused only on the results of the 55 thoracoscopic procedures performed for diagnostic purposes in 19 cases (34.6%) and for therapeutic purposes in 36 cases (65.4%).Results: The duration of surgery was 15 to 180 min (median, 65 min). Metastasectomies were performed for various etiologies in 31 of the 55 cases. Of the 55 patients, 5 underwent resection of a mediastinal tumor, and 19 underwent a diagnostic thoracoscopy. During a mean follow-up period of 25.6 months, 2 (3.6%) of the 55 patients experienced perioperative complications.Conclusions: The role of MIS in tumor resection for children is currently limited, but may be used in individual cases when the preoperative workup shows it to be feasible. Its indication is strictly dependent on the thoracoscopic experience of the surgeon and the tumor site for preoperative imaging techniques. When the indication for thoracoscopy is correct, this approach has high therapeutic applicability (65.4% in our series). Our preliminary experience shows that careful patient selection and an appropriate level of technical skill make thoracoscopy a reasonable and safe option for the treatment of pediatric malignancies. [ABSTRACT FROM AUTHOR]

Background: The aim of this study was to evaluate the incidence and management of complications of videosurgical procedures that occurred during a 4-year period in eight Italian pediatric surgery centers.Methods: Between 1996 and 1999, 2305 videosurgical procedures were performed in 11 centers of pediatric surgery. The data from 3 centers, for a total of 616 procedures, were largely incomplete and were thus excluded from the study. We analyzed the data from 8 centers only, for a total of 1689 laparoscopic or thoracoscopic operations on patients aged between 15 days and 16 years. The type of operations performed ranged from basic videosurgical interventions, such as varicocelectomy and cryptorchidism, to advanced laparoscopic procedures, such as splenectomy, total colectomy, and esophageal achalasia. Each patient's file was examined for any complications that may have occurred during the surgical procedure and for a record of how these were managed.Results: We recorded 79 complications (4.6%) in our series. In 57 cases (72.2%) the problem was solved by videosurgery. Twenty-two cases (27.8%) required conversion to open surgery. There was no mortality in our series. At a maximum follow-up of 4 years, all children were alive and had no problems related to the videosurgical complications.Conclusions: We believe that the routine use of open laparoscopy in pediatric patients is a key factor to avoiding complications related to the Veress needle and blind introduction of the first trocar. Moreover, the surgeon's laparoscopic experience, the correct indications for laparoscopic surgery, and the verification of the laparoscopic equipment before surgery are also important rules to follow to reduce the incidence of complications. In the beginning, it is preferable to have the assistance of an expert laparoscopic surgeon to decrease the complications related to the learning curve period. [ABSTRACT FROM AUTHOR]

To meet the world's demands on the development of sunlight-powered renewable energy production, triplet-triplet annihilation-based photon upconversion (TTA-UC) has raised great expectations. However, an ideal highly efficient, low-power, and in-air TTA-UC has not been achieved. Here, we report a novel self-assembly approach to achieve this, which enabled highly efficient TTA-UC even in the presence of oxygen. A newly developed lipophilic 9,10-diphenylanthracene-based emitter molecule functionalized with multiple hydrogen-bonding moieties spontaneously coassembled with a triplet sensitizer in organic media, showing efficient triplet sensitization and subsequent triplet energy migration among the preorganized chromophores. This supramolecular light-harvesting system shows a high UC quantum yield of 30% optimized at low excitation power in deaerated conditions. Significantly, the UC emission largely remains even in an air-saturated solution, and this approach is facilely applicable to organogel and solid-film systems. [ABSTRACT FROM AUTHOR]