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The Berlin Grading System assesses clinical severity of moyamoya angiopathy (MMA) by combining MRI, DSA, and cerebrovascular reserve capacity (CVRC). Our aim was to validate this grading system using [15O]H2O PET for CVRC. We retrospectively identified bilateral MMA patients who underwent [15O]H2O PET examination and were treated surgically at our department. Each hemisphere was classified using the Suzuki and Berlin Grading System. Preoperative symptoms and perioperative ischemias were collected, and a logistic regression analysis was performed. A total of 100 hemispheres in 50 MMA patients (36 women, 14 men) were included. Using the Berlin Grading System, 2 (2.8%) of 71 symptomatic hemispheres were categorized as grade I, 14 (19.7%) as grade II, and 55 (77.5%) as grade III. The 29 asymptomatic hemispheres were characterized as grade I in 7 (24.1%) hemispheres, grade II in 12 (41.4%), and grade III in 10 (34.5%) hemispheres. Berlin grades were independent factors for identifying hemispheres as symptomatic and higher grades correlated with increasing proportion of symptomatic hemispheres (p < 0.01). The Suzuki grading did not correlate with preoperative symptoms (p = 0.26). Perioperative ischemic complications occurred in 8 of 88 operated hemispheres. Overall, complications did not occur in any of the grade I hemispheres, but in 9.1% (n = 2 of 22) and 9.8% (n = 6 of 61) of grade II and III hemispheres, respectively. In this study, we validated the Berlin Grading System with the use of [15O]H2O PET for CVRC as it could stratify preoperative symptomatology. Furthermore, we highlighted its relevance for predicting perioperative ischemic complications. [ABSTRACT FROM AUTHOR]

The gold drugs, gold sodium thiomalate (Myocrisin), aurothioglucose (Solganal), and the orally administered auranofin (Ridaura), are utilized in modern medicine for the treatment of inflammatory arthritis including rheumatoid and juvenile arthritis; however, new gold agents have been slow to enter the clinic. Repurposing of auranofin in different disease indications such as cancer, parasitic, and microbial infections in the clinic has provided impetus for the development of new gold complexes for biomedical applications based on unique mechanistic insights differentiated from auranofin. Various chemical methods for the preparation of physiologically stable gold complexes and associated mechanisms have been explored in biomedicine such as therapeutics or chemical probes. In this Review, we discuss the chemistry of next generation gold drugs, which encompasses oxidation states, geometry, ligands, coordination, and organometallic compounds for infectious diseases, cancer, inflammation, and as tools for chemical biology via gold–protein interactions. We will focus on the development of gold agents in biomedicine within the past decade. The Review provides readers with an accessible overview of the utility, development, and mechanism of action of gold-based small molecules to establish context and basis for the thriving resurgence of gold in medicine. [ABSTRACT FROM AUTHOR]

[Display omitted] • Redox neutral, oxidant-free gold catalysis. • Homogenous catalysis under aerobic conditions by distorted tri-coordinate Au(I) catalyst. • Air-, bench-stable gold catalysts. • Biaryl synthesis of aryl-iodide and C-H arene coupling partners providing moderate to high yields. The development of oxidant-free gold-catalyzed cross coupling reactions involving aryl halides have been hamstrung by the lack of gold catalysts capable of performing oxidative addition at Au(I) centers. Herein, we report the development of novel tricoordinate Au(I) catalysts supported by N,N-bidentate ligands and ligated by phosphine or arsine ligands for C-H functionalization without external oxidants to form biaryls with no homocoupling. The unsymmetrical character of the Au(I) catalyst is critical to facilitating this necessary orthogonal transformation. This study unveils yet another potential of Au(I) catalysis in biaryl synthesis. [ABSTRACT FROM AUTHOR]

Triple-negative breast cancer (TNBC) is associated with metabolic heterogeneity and poor prognosis with limited treatment options. New treatment paradigms for TNBC remains an unmet need. Thus, therapeutics that target metabolism are particularly attractive approaches. We previously designed organometallic Au(III) compounds capable of modulating mitochondrial respiration by ligand tuning with high anticancer potency in vitro and in vivo. Here, we show that an efficacious Au(III) dithiocarbamate (AuDTC) compound induce mitochondrial dysfunction and oxidative damage in cancer cells. Efficacy of AuDTC in TNBC mouse models harboring mitochondrial oxidative phosphorylation (OXPHOS) dependence and metabolic heterogeneity establishes its therapeutic potential following systemic delivery. This provides evidence that AuDTC is an effective modulator of mitochondrial respiration worthy of clinical development in the context of TNBC. Metabolic-targeting of triple-negative breast cancer by gold anticancer agent may provide efficacious therapy. [ABSTRACT FROM AUTHOR]

Imidazolium salts are common building blocks for functional materials and in the synthesis of N-heterocyclic carbene (NHC) as σ-donor ligands for stable metal complexes. The title salt, 1,3-bis­(4-hy­droxy­phen­yl)-1H-imidazol-3-ium chloride (IOH·Cl), C15H13N2O2+·Cl−, is a new imidazolium salt with a hy­droxy functionality. The synthesis of IOH·Cl was achieved in high yield via a two-step procedure involving a di­aza­butadiene precursor followed by ring closure using tri­methylchloro­silane and paraformaldehyde. The structure of IOH·Cl consists of a central planar imidazolium ring (r.m.s. deviation = 0.0015 Å), with out-of-plane phenolic side arms. The dihedral angles between the 4-hy­droxy­phenyl substituents and the imidazole ring are 55.27 (7) and 48.85 (11)°. In the crystal, O—H···Cl hydrogen bonds connect the distal hy­droxy groups and Cl− anions in adjacent asymmetric units, one related by inversion (−x + 1, −y + 1, −z + 1) and one by the n-glide (x − ½, −y + ½, z − ½), with donor–acceptor distances of 2.977 (2) and 3.0130 (18) Å, respectively. The phenolic rings are each π–π stacked with their respective inversion-related [(−x + 1, −y + 1, −z + 1) and (−x, −y + 1, −z + 1)] counterparts, with inter­planar distances of 3.560 (3) and 3.778 (3) Å. The only other noteworthy inter­molecular inter­action is an O...O (not hydrogen bonded) close contact of 2.999 (3) Å between crystallographically different hy­droxy O atoms on translationally adjacent mol­ecules (x + 1, y, x + 1). [ABSTRACT FROM AUTHOR]

The reactivity of bidentate AuIII–Cl species, [(C^N)AuCl2], with a bisphosphine or carbon donor ligands results in reductive elimination. Combined experimental and computational investigations lead to the first evidence of a direct intramolecular C(sp2)–N(sp2) bond formation from a monomeric [(C^N)AuCl2] gold(iii) complex. We show that bidentate ligated Au(iii) systems bypass transmetallation to form C(sp2)–N(sp2) species and NHC–Au–Cl. Mechanistic investigations of the reported transformation reveal a ligand-induced reductive elimination via a key AuIII intermediate. Kinetic studies of the reaction support a second-order rate process. [ABSTRACT FROM AUTHOR]

The reactivity of tetrachloroauric acid (HAuCl4) with readily accessible bidentate N-donor ligands affords N,N-ligated Au(iii) center complexes. These compounds are useful precursors of stable catalysts, anticancer agents, and building blocks for materials. This report provides detailed insight into intermediates, equilibria, the counter anion effect, and structural variability, using spectroscopy, crystallography and computational tools. Novel mixed-valence Au(i) and Au(iii) complexes [Au(o-phen)Cl2]2[AuCl2][AuCl4] and [Au(o-phen)Cl2][AuCl2] having AuCl2− and AuCl4− anions linearly arranged in the axial sites of the square-planar Au(o-phen)Cl2 cation were discovered. Other competing side products of the reaction studied revealed protonated N,N-bidentate ligands with AuCl4− anions. Quantitative variable temperature NMR studies reveal that for a mixture of target Au(iii) salt and the protonated ligand, the reaction favors the irreversible formation of the side product. Using a rapid (30 min) temperature controlled protocol, the desired coordinated species is accessible in respectable yields while avoiding side products. [ABSTRACT FROM AUTHOR]

Presents a study that proposed a theory for the junction capacitance of mathematically abrupt diodes. Derivation of a general junction capacitance formula; Information on a capacitance formula for an abrupt junction; Evaluation of the general capacitance formula for symmetrical and asymmetrical abrupt junction.

Adherence is now one of the major issues in the management of osteoporosis and several papers have suggested that vertebral fractures might be increased in patients who do not follow appropriately their prescriptions. This paper relates the strong relationship existing between adherence to anti-osteoporosis treatment and the risk of subsequent hip fracture. A study was performed to investigate adherence to bisphosphonate (BP) therapy and the impact of adherence on the risk of hip fracture (Fx). An exhaustive search of the Belgian national social security database was conducted. Patients enrolled in the study were postmenopausal women, naïve to BP, who received a first prescription of alendronate. Compliance at 12 months was quantified using the medication possession ratio (MPR). Persistence was calculated as the number of days from the initial prescription to a gap of more than 5 weeks after completion of the previous refill. A logistic regression model was used to estimate the impact of compliance on the risk of hip fracture. The impact of persistence on hip fracture risk was analysed using the Cox proportional hazards model. The mean MPR at 12 months was significantly higher among patients receiving weekly ( n = 15.021) compared to daily alendronate ( n = 14,136) (daily = 58.6%; weekly = 70.5%; p < 0.001). At 12 months, the rate of persistence was 39.45%. For each decrease of the MPR by 1%, the risk of hip Fx increased by 0.4% (OR: 0.996; CI95%:0.994–0.998; p < 0.001). The relative risk reduction for hip Fx was 60% (HR: 0.404;CI95%:0.357–0.457; p < 0.0001) for persistent compared to non-persistent patients. These results confirm that adherence to current therapeutic regimens remains suboptimal. [ABSTRACT FROM AUTHOR]

B/Nb and B/Nb2N bilayers and Nb/B/Nb trilayers of about 550 nm total thickness have been deposited on Si(100) wafers with 100 nm thermally grown oxide. Nb and B layers were deposited by magnetron sputtering. Nb2N layers were prepared by nitridation of Nb films via rapid thermal processing (RTP). The samples were annealed subsequently at temperatures between 600 and 1,200 °C in an RTP system under Ar or NH3 gas flow to study interdiffusion and reactivity of niobium, boron and nitrogen. Formation of phases was investigated by X-ray diffraction (XRD); surface morphology and roughness were studied via scanning electron microscopy (SEM) and atomic force microscopy (AFM), respectively. Elemental depth profiles of selected samples were recorded by secondary ion mass spectrometry (SIMS). Annealing of the B/Nb bilayers and Nb/B/Nb trilayers under Ar leads to the formation of Nb3B2 at 1,200 °C at the B/Nb interface. At lower temperatures the high oxygen content in the boron layer is supposed to hinder the formation of borides due to formation of glass-like boron oxides. In NH3 several niobium nitrides are formed but no boride phases. Here again the reactivity of boron with niobium is suppressed by the high oxygen content and boron oxide formation. During annealing of the B/Nb2N bilayers no borides were formed indicating that well-formed Nb2N is an effective diffusion barrier for B. [ABSTRACT FROM AUTHOR]

The increase of the electrical conductivity of the arylenevinylene (AV) system 1,4-bis[2-(3,4,5-trimethoxyphenyl)ethenyl] benzene was measured as a function of the doping level of iodine. Compressed powders and films blended with polystyrene (PS) containing up to 30 wt.% of the oligomer were used. At the highest doping level the conductivity of the compressed powder reaches a value of 3.3×10−4 Ω−1 cm−1. The conductivity, measured between 90 and 300 K on the powder with the highest conductivity, is thermally activated with an activation energy of ∼0.1 eV. The thermopower is positive in agreement with a charge transfer from the organic chain to an iodine atom. Its value is small (25 μV K−1) and temperature independent. The results are interpreted in terms of small-polaron hopping. [Copyright &y& Elsevier]

Amorphous AsxS100−x films were prepared by thermal evaporation and plasma-enhanced chemical vapour deposition (PECVD). Reversible photodarkening upon illumination with white light at 300 and 77 K was studied for both types of films. The magnitude of photodarkening increased with increasing As content, being somewhat larger for the evaporated films than for the PECVD ones. In agreement with our previous observations in the amorphous As–Se and Ge–Se systems, the shift of the optical absorption edge was not parallel but was always accompanied by a decrease in the slope of the Tauc curve, indicating an increase in disorder. The kinetics of the photoinduced optical shift could be best described by a stretched exponential law. This can be explained within Tanaka''s “single–double well model” with the addition that the process is most probably a kind of self-limiting process, whereby excitation to a quasi-stable state (photodarkening) and annealing (thermal and photoinduced) are simultaneously operative. [Copyright &y& Elsevier]

Cu(II)-dithiooxamide polymers were prepared by a direct deprotonation of the ligand with a Cu(II) salt. The polymers had a chain length of about 13 units. The undoped polymers showed low electrical conductivity with an Arrhenius-type temperature dependence. Doping of Cu(II)-N,N′-dimethyldithiooxamide was performed by iodine in the vapour phase and by FeCl3 in solution. In both cases, the oxidative doping resulted in highly increased conductivities. A thermopower measurement indicated p-type conduction. The infrared spectra of the undoped material and the one doped with FeCl3 were completely identical, indicating that charge transfer from the ligand to the dopant is small. The conductivity curves of the doped polymer did not show an Arrhenius-type behaviour. In order to find an explanation for the conduction mechanism different models were tested. The best fit of the experimental conductivity data of the FeCl3-doped polymers was obtained with the theoretical prediction of a variable-range hopping model. [Copyright &y& Elsevier]

A common side effect of chemotherapy is reversible or nonreversible nephrotoxicity. SDS polyacrylamide gel electrophoresis combined with laser densitometry was evaluated as a suitable method to analyze pathologic urine proteins. A total of 52 pediatric patients were followed during and 63 patients were followed after therapy. During therapy renal damage was recorded in 43% of the leukemia patients, in 56% of nephroblastoma patients, and 75% of patients with other tumors. Three or more months after therapy pathologic patterns were seen in 25% of acute lymphoblastic leukemia patients, in 35% of patients with nephroblastoma, and in 62% of other patients. Patients with persistent complete tubular proteinuria and mixed glomerular/tubular proteinuria were found to have a high risk for irreversible renal damage and should be controlled periodically. This method permits a rapid and reliable analysis of urine proteins and is suitable for follow-up tests of renal function during and after chemotherapy. [ABSTRACT FROM AUTHOR]

Unlabelled: Hepatic veno-occlusive disease (VOD) is a well-known complication of chemotherapy in Wilms tumor patients, particularly young children. Although this complication resolves uneventfully in most patients, fatal cases have been reported. Severe VOD after transplantation has a high mortality rate ranging from 45% to 98%. New hemostatic therapeutic strategies have significantly improved the prognosis of VOD. Chemotherapy-related VOD in Wilms tumor usually has a good prognosis. We describe two patients with Wilms tumor and one with acute lymphoblastic leukemia, who developed severe veno-occlusive disease of the liver according to the Baltimore criteria while undergoing chemotherapy; the symptoms were hepatomegaly, ascites, hyperbilirubinemia, weight gain and, in one patient, short-term lethargy. Elevated LDH levels of 872 to 12,000 U/l were observed in our patients. All patients had thrombocytopenia between 29,000 and 40,000/microl and decreased antithrombin (AT) and protein C levels; two patients had gastrointestinal bleeding. All patients developed a coagulopathy because of severe hepatic dysfunction. Two patients received low-dose heparin at the onset of VOD. The thrombolytic therapy was rapidly changed to AT supplementation (20-80 IU/kg bw 2x per day) without heparin when thrombocytes were very low or gastrointestinal bleeding occurred. Resolution of VOD was observed in all patients receiving AT alone. The chemotherapy was discontinued in a patient with accidental actinomycin D overdosage in view of the severity of symptoms. The remaining two patients received chemotherapy according to the therapy protocol after restitution. All patients survived without sequelae with a median follow-up of 28 months (range 8-48 months).Conclusion: Hepatic veno-occlusive disease is a rare but increasingly recognized complication in pediatric cancer patients receiving conventional chemotherapy. AT supplementation constitutes a good alternative treatment of severe VOD in comparison with other thrombolytic therapies, particularly in patients at high risk of bleeding. [ABSTRACT FROM AUTHOR]

Herein is reported the synthesis of two Au(III) complexes bearing the (R,R)-(–)-2,3-Bis(tert-butylmethylphosphino)quinoxaline (R,R-QuinoxP*) or (S,S)-(+)-2,3-Bis(tert-butylmethylphosphino)quinoxaline (S,S-QuinoxP*) ligands. By reacting two stoichiometric equivalents of HAuCl4.3H2O to one equivalent of the corresponding QuinoxP* ligand, (R,R)-(–)-2,3-Bis(tert-butylmethylphosphino)quinoxalinedichlorogold(III) tetrachloroaurates(III) (1) and (S,S)-(+)-2,3-Bis(tert-butylmethylphosphino)quinoxalinedichlorogold(III) tetrachloroaurates(III) (2) were formed, respectively, in moderate yields. The structure of (S,S)-(+)-2,3-Bis(tert-butylmethylphosphino)quinoxalinedichlorogold(III) tetrachloroaurates(III) (2) was further confirmed by X-ray crystallography. The antiproliferative activities of the two compounds were evaluated in a panel of cell lines and exhibited promising results comparable to auranofin and cisplatin with IC50 values between 1.08 and 4.83 µM. It is noteworthy that in comparison to other platinum and ruthenium enantiomeric complexes, the two enantiomers (1 and 2) do not exhibit different cytotoxic effects. The compounds exhibited stability in biologically relevant media over 48 h as well as inert reactivity to excess glutathione at 37 °C. These results demonstrate that the Au(III) atom, stabilized by the QuinoxP* ligand, can provide exciting compounds for novel anticancer drugs. These complexes provide a new scaffold to further develop a robust and diverse library of chiral phosphorus Au(III) complexes. [ABSTRACT FROM AUTHOR]

COVID-19 can induce neurological sequelae, negatively affecting the quality of life. Unravelling this illness's impact on structural brain connectivity, white-matter microstructure (WMM), and cognitive performance may help elucidate its implications. This cross-sectional study aimed to investigate differences in these factors between former hospitalised COVID-19 patients (COV) and healthy controls. Group differences in structural brain connectivity were explored using Welch-two sample t-tests and two-sample Mann–Whitney U tests. Multivariate linear models were constructed (one per region) to examine fixel-based group differences. Differences in cognitive performance between groups were investigated using Wilcoxon Rank Sum tests. Possible effects of bundle-specific FD measures on cognitive performance were explored using a two-group path model. No differences in whole-brain structural organisation were found. Bundle-specific metrics showed reduced fiber density (p = 0.012, Hedges' g = 0.884) and fiber density cross-section (p = 0.007, Hedges' g = 0.945) in the motor segment of the corpus callosum in COV compared to healthy controls. Cognitive performance on the motor praxis and digit symbol substitution tests was worse in COV than healthy controls (p < 0.001, r = 0.688; p = 0.013, r = 422, respectively). Associations between the cognitive performance and bundle-specific FD measures differed significantly between groups. WMM and cognitive performance differences were observed between COV and healthy controls. [ABSTRACT FROM AUTHOR]

An abstract of the article "Adherence to Biphosphonates and Hip Fracture Risk," by V. Rabenda, R. Mertens, V. Fabri, J. Vanoverloop, F. Sumkay, C. Vannecke, A. Deswaef, G.A. Verpooten and J.Y. Reginster is presented.

The altered posterior question-mark incision for decompressive hemicraniectomy (DHC) was proposed to reduce the risk of intraoperative injury of the superficial temporal artery (STA) and demonstrated a reduced rate of wound-healing disorders after cranioplasty. However, decompression size during DHC is essential and it remains unclear if the new incision type allows for an equally effective decompression. Therefore, this study evaluated the efficacy of the altered posterior question-mark incision for craniectomy size and decompression of the temporal base and assessed intraoperative complications compared to a modified standard reversed question-mark incision. The authors retrospectively identified 69 patients who underwent DHC from 2019 to 2022. Decompression and preservation of the STA was assessed on postoperative CT scans and CT or MR angiography. Forty-two patients underwent DHC with the standard reversed and 27 patients with the altered posterior question-mark incision. The distance of the margin of the craniectomy to the temporal base was 6.9 mm in the modified standard reversed and 7.2 mm in the altered posterior question-mark group (p = 0.77). There was no difference between the craniectomy sizes of 158.8 mm and 158.2 mm, respectively (p = 0.45), and there was no difference in the rate of accidental opening of the mastoid air cells. In both groups, no transverse/sigmoid sinus was injured. Twenty-four out of 42 patients in the modified standard and 22/27 patients in the altered posterior question-mark group had a postoperative angiography, and the STA was preserved in all cases in both groups. Twelve (29%) and 5 (19%) patients underwent revision due to wound-healing disorders after DHC, respectively (p = 0.34). There was no difference in duration of surgery. Thus, the altered posterior question-mark incision demonstrated technically equivalent and allows for an equally effective craniectomy size and decompression of the temporal base without increasing risks of intraoperative complications. Previously described reduction in wound-healing complications and cranioplasty failures needs to be confirmed in prospective studies to demonstrate the superiority of the altered posterior question-mark incision. [ABSTRACT FROM AUTHOR]

Background: Long-term sequelae of COVID-19 can result in reduced functionality of the central nervous system and substandard quality of life. Gaining insight into the recovery trajectory of admitted COVID-19 patients on their cognitive performance and global structural brain connectivity may allow a better understanding of the diseases' relevance. Objectives: To assess whole-brain structural connectivity in former non-intensive-care unit (ICU)- and ICU-admitted COVID-19 survivors over 2 months following hospital discharge and correlate structural connectivity measures to cognitive performance. Methods: Participants underwent Magnetic Resonance Imaging brain scans and a cognitive test battery after hospital discharge to evaluate structural connectivity and cognitive performance. Multilevel models were constructed for each graph measure and cognitive test, assessing the groups' influence, time since discharge, and interactions. Linear regression models estimated whether the graph measurements affected cognitive measures and whether they differed between ICU and non-ICU patients. Results: Six former ICU and six non-ICU patients completed the study. Across the various graph measures, the characteristic path length decreased over time (β = 0.97, p = 0.006). We detected no group-level effects (β = 1.07, p = 0.442) nor interaction effects (β = 1.02, p = 0.220). Cognitive performance improved for both non-ICU and ICU COVID-19 survivors on four out of seven cognitive tests 2 months later (p < 0.05). Conclusion: Adverse effects of COVID-19 on brain functioning and structure abate over time. These results should be supported by future research including larger sample sizes, matched control groups of healthy non-infected individuals, and more extended follow-up periods. [ABSTRACT FROM AUTHOR]

Abstract Hepatic veno-occlusive disease (VOD) is a well-known complication of chemotherapy in Wilms tumor patients, particularly young children. Although this complication resolves uneventfully in most patients, fatal cases have been reported. Severe VOD after transplantation has a high mortality rate ranging from 45% to 98%. New hemostatic therapeutic strategies have significantly improved the prognosis of VOD. Chemotherapy-related VOD in Wilms tumor usually has a good prognosis. We describe two patients with Wilms tumor and one with acute lymphoblastic leukemia, who developed severe veno-occlusive disease of the liver according to the Baltimore criteria while undergoing chemotherapy; the symptoms were hepatomegaly, ascites, hyperbilirubinemia, weight gain and, in one patient, short-term lethargy. Elevated LDH levels of 872 to 12,000 U/1 were observed in our patients. All patients had thrombocytopenia between 29,000 and 40,000/mu l and decreased antithrombin (AT) and protein C levels; two patients had gastrointestinal bleeding. All patients developed a coagulopathy because of severe hepatic dysfunction. Two patients received low-dose heparin at the onset of VOD. The thrombolytic therapy was rapidly changed to AT supplementation (20-80 IU/kg bw 2x per day) without heparin when thrombocytes were very low or gastrointestinal bleeding occurred. Resolution of VOD was observed in all patients receiving AT alone. The chemotherapy was discontinued in a patient with accidental actinomycin D overdosage in view of the severity of symptoms. The remaining two patients received chemotherapy according to the therapy protocol after restitution. All patients survived without sequelae with a median follow-up of 28 months (range 848 months). Conclusion Hepatic veno-occlusive disease is a rare but increasingly recognized complication... [ABSTRACT FROM AUTHOR]

The inlet patch is an area of heterotopic gastric mucosa most commonly located in the postcricoid portion of the esophagus at, or just below, the level of the upper esophageal sphincter. Esophageal and supraesophageal symptoms are commonly associated with inlet patch, while esophageal adenocarcinoma rarely complicates it. Laryngeal adenocarcinoma associated with inlet patch is not described in the literature. Herein, we present the first reported case of inlet patch associated with laryngeal carcinoma. A 33-year-old female with long-standing asthma and presumed gastroesophageal reflux developed laryngeal cancer at age 22 years that was treated with concomitant radiation and induction chemotherapy. Subsequently, she had refractory heartburn, dysphagia, and cough. These symptoms continued despite two Nissen fundoplications, glottic web division, and optimal medical management. Upper endoscopy at our institution revealed an upper esophageal stricture and a 1 cm inlet patch. Biopsies showed columnar mucosa (predominantly gastric cardiac/fundic type) consistent with inlet patch, with focal intestinal metaplasia. Subsequent endoscopic mucosal resection of the inlet patch resulted in an amelioration of throat and chest pain, cough, and hoarseness. Dysphagia and regurgitation were improved by serial dilatations of the upper esophageal stricture. This case reveals a number of clinical findings associated with inlet patch – chest pain, dysphagia, cough, and hoarseness – as well as a clinical finding that has not been previously associated with inlet patch: laryngeal cancer. Symptoms refractory to optimal medical management and/or surgical intervention should make the clinician and endoscopist more cognizant of the inlet patch. [ABSTRACT FROM AUTHOR]

We have studied the Cr7C3 phase by means of ab initio calculations and found covalent-ionic Cr–C–Cr chains in a metallic matrix. Furthermore, the structure of thin films, synthesized by RF magnetron sputtering, is shown to be in good agreement with our theoretical prediction. [Copyright &y& Elsevier]

Deals with a study of the dark current increase due to proton-induced displacement damage in a standard and a radiation-hardened complementary metal oxide semiconductor active pixel sensor. Experimental details; Dark current density histogram; Comparison to other solid-state sensors; Conclusion.

Discusses the random telegraph signal (RTS) behavior of the dark current in a radiation-hardened complementary metal oxide semiconductor active pixel sensor. Data on the dark current pedestal, RTS amplitudes, time constraints and temperature behavior; Discussion on a general model for the introduction probability of RTS behavior; Correlation between probability of RTS occurrence and dark current density.

Abstract. In atom lithography the conventional roles played by light and matter are reversed. Instead of using a solid mask to pattern a light beam, a mask of light is used to pattern a beam of neutral atoms. In this paper we report the production of different chromium dot arrays with quadratic symmetry. The lattice period depends on the relative polarization and the phase of the two standing waves generating the light mask. A small angular misalignment of the laser beams breaks the high symmetry and a chromium superlattice is written, that is a continuous periodic change between two different quadratic lattices. The structures exhibit lines with a FWHM below 50 nm and clearly separated chromium dots with a FWHM below 70 nm. [ABSTRACT FROM AUTHOR]

Abstract: This work presents the design and test result of a standard 0.7μm CMOS flash analog-to-digital converter (ADC) operational in an ultra wide temperature range (UWT, room temperature down to 4.2K). To maintain the circuit’s performance over the UWT range in the presence of temperature induced transistor anomalies, dedicated topology and switching schemes are utilized. Test results mentioned in this text are from a single process run, no design iterations were made. [Copyright &y& Elsevier]

A model to calculate the current voltage characteristics of organic thin film transistors is presented. The model takes into account the influence of high electric field on trap occupancy. The case of the traps at a single energy level is considered in detail. Relevant equations are solved numerically using an iteration method. The field dependent trap occupancy model is found to change free surface charge Q[sub sf] and drain saturation current I[sub d] significantly. The model is compared with the experimental data published by two different groups. There is good agreement between experimental data and our model. © 2003 American Institute of Physics. [ABSTRACT FROM AUTHOR]

The space charge limited currents J in conducting organic materials often show J∼V[sup m] (where m > 2) dependence on voltage V. Two models have been used extensively to understand this behavior. In one model, the mobility μ is assumed to be dependent on electric field F. In the other model, an exponential distribution of traps is assumed and the mobility is taken to be independent of field. In this model the influence of the high electric fields present in organic polymers has not been taken into account. We present a model to calculate the J(V) characteristics for single carrier organic polymers taking into account the change in the occupancy of the traps due to the high electrical fields present in these materials. We show that the field dependent trap occupancy (FDTO) model can effectively explain the current-voltage characteristics reported by several different groups. If the FDTO model is used, it is not necessary to use the two different models mentioned above. [ABSTRACT FROM AUTHOR]

We improve the trapping model of carrier transport in conducting polymers by integrating the coupled Poisson and continuity equations numerically. In the case of exponentially distributed traps calculated log J vs 1/T plots are straight lines indicating that the activation of carriers to the extended states can be described by one single activation energy, E[sub eff]. The improved trapping model agrees well with the recent experimental data at high temperatures (i.e., near room temperature). At low temperatures the trapping model does not work since the available thermal energy is not sufficient to ionize the traps. We use the hopping mobility model at low temperatures. The model explains the low-temperature J-V characteristics well. This mechanism of charge carrier transport is similar to that used for interpreting experiments on inorganic amorphous materials. [ABSTRACT FROM AUTHOR]

Focuses on a study which detailed the calculation of the interaction energy of arrays of dislocations with nonperiodic distribution. Reason for conducting the calculations; Focus of studies on strain relaxation in pseudomorphic epilayers; Situation in which the calculated rate of strain relaxation on annealing the metastable layers at higher temperatures is increased.

Presents a study that have grown epitaxial layers of silicon-doped indium-arsenic-antimony by molecular-beam epitaxy on gallium arsenide (GaAs) and GaAs-coated silicon substrates. Absorption coefficient; Use of the fitted value of the Fermi level; Electron concentration.

Focuses on a study which determined the properties of doped and undoped amorphous silicon films deposited by the homogenous chemical vapor deposition (HOMOCVD) technique. Information on HOMOCVD; Methodology of the study; Results and discussion.

Studies band-gap narrowing of gallium arsenide as a function of doping concentration using photoluminescence spectroscopy on samples grown by molecular epitaxy. Technique used in measuring the band gap energy; Details on the experiment; Discussion on the results of the study.

Provides information on a study which examined the infrared response of polycrystalline and epitaxial cobalt silicon[sub2]/silicon Schottky diodes as a function of the silicide thickness. Influence of grain boundary scattering on the silicide; Quantum efficiency of the polycrystalline diodes.

Presents a study that examined the fabrication of conventional and electromagnetically casted multicrystalline silicon solar cells using different passivation schemes. Implementation of plasma-enhanced chemical-vapor-deposition; Information on multicrystalline silicon; Discussion on hydrogen plasma passivation.

Space charge limited currents in organic semiconductors are frequently observed to obey the power law J-V[SUPm] and are attributed to an exponential distribution of traps having two parameters, namely the characteristic distribution energy E[SUBt] and the trap concentration H[SUBt]. We determine these parameters from the J(V) characteristics at two or more temperatures reported in literature. [ABSTRACT FROM AUTHOR]

According to the approximate theory of transport in a conducting organic material containing exponential traps, ln J versus In V plots are straight lines with slope l= T[sub C]/T, where T[sub c] is the characteristic temperature of the trap distribution. It is assumed in this theory that the concentration P[sub t] of trapped holes is much larger than the concentrationp of free holes. Our experiments and recent literature results show that at high applied voltages the observed In d versus In V plots deviate from the straight lines and bend down. The numerical solution presented in this article shows that at high voltages the contribution of p to the space charge does not remain negligible. Calculated In d versus In V plots do bend down consistent with our experimental results. The current approaches the trap-filled limit asymptotically as the applied voltage approaches infinity. [ABSTRACT FROM AUTHOR]

In this paper we propose a possible process simplification for pseudosquare 15.6×15.6 cm 2 Interdigitated Back Contact (IBC) CZ-Si solar cells. By using laser doping to create a selective BSF, one out of three diffusions and a wet etching step can be avoided, compared to a completely diffusion-based process flow. We show numerical optimization of this simplified cell structure in terms of: i) rear optics with additional SiN x capping layer, ii) contact fraction of the selective BSF. The results feature a top cell efficiency of 21.7% measured over the area of 239 cm 2 . Further characterization implies that cells were limited mainly by: i) FF losses attributed to lateral majority carrier transport in the BSF region and increased J 02 losses, ii) current loss which can be related to the BSF region. [ABSTRACT FROM AUTHOR]

In the future solar devices will be manufactured onto thin mono-crystalline silicon wafers (foils) potentially bonded to substrate carriers. In this study, the influence of the substrate carrier potential (grounded or floating) on the amorphous silicon a-Si:H surface passivation of the bonded foil is discussed for the cases of conductive and insulating substrate carriers. A conductive carrier leads to an increase in deposition rate and ion bombardment energy, which is detrimental for sample lifetime. An insulating carrier, e.g., a glass substrate, inverts the trend and improves the a-Si:H surface passivation. [ABSTRACT FROM AUTHOR]

We have investigated fine grained polycrystalline silicon thin films grown by direct chemical vapor deposition on oxidized silicon substrates. More specifically, we analyze the influence of the doping type on the properties of this model polycrystalline silicon material. This includes an investigation of defect passivation and benchmarking of minority carrier properties. In our investigation, we use a variety of characterization techniques to probe the properties of the investigated polycrystalline silicon thin films, including Fourier Transform Photoelectron Spectroscopy, Electron Spin Resonance, Conductivity Activation, and Suns-Voc measurements. Amphoteric silicon dangling bond defects are identified as the most prominent defect type present in these layers. They are the primary recombination center in the relatively lowly doped polysilicon thin films at the heart of the current investigation. In contrast with the case of solar cells based on Czochralski silicon or multicrystalline silicon wafers, we conclude that no benefit is found to be associated with the use of n-type dopants over p-type dopants in the active absorber of the investigated polycrystalline silicon thin-film solar cells. [ABSTRACT FROM AUTHOR]

Background: The authors report preliminary results from a prospective multicenter study (Nasopharyngeal Carcinoma [NPC] 2003 German Society of Pediatric Oncology and Hematology/German Children's Oncology Group [NPC-2003-GPOH/DCOG]). Methods: From 2003 to 2010, 45 patients (ages 8-20 years), including 1 patient with stage II NPC and 44 patients with stage III/IV NPC, were recruited to the study. The patient with stage II disease received radiotherapy (59.4 grays [Gy]). The patients with stage III/IV disease received 3 courses of neoadjuvant chemotherapy with cisplatin, 5-fluorouracil, and folinic acid. The cumulative irradiation dose was 54 Gy in 5 patients, who achieved complete remission after neoadjuvant chemotherapy, and 59.4 Gy in the remaining 40 patients. All patients received concomitant cisplatin during the first week and last week of irradiation. After irradiation, all patients received interferon beta for 6 months. Tumor response was evaluated by magnetic resonance imaging studies and positron emission tomography scans. Results: After the completion of treatment, 43 of 45 patients were in complete remission. In 2 patients, only a partial response was achieved, followed by distant metastases (1 patient) or local progression and distant metastases (1 patient), 6 months and 10 months after diagnosis, respectively. Another patient developed a solitary pelvic bone metastasis 21 months after diagnosis. After a median follow-up of 30 months (range, 6-95 months), the event-free survival rate was 92.4%, and the overall survival was 97.1%. Acute toxicity consisted mainly of leucopenia, mucositis, and nausea; and late toxicity consisted of hearing loss and hypothyroidism. Conclusions: Combined therapy with neoadjuvant chemotherapy, radiochemotherapy, and interferon beta was well tolerated and resulted in a very good outcome that was superior to the outcomes of published results from all other pediatric NPC study groups. [ABSTRACT FROM AUTHOR]

Abstract: Random Al back surface field (BSF) p-type Si solar cells are presented, where a stack of Al2O3 and SiN x is used as rear surface passivation layer containing blisters. It is shown that no additional contact opening step is needed, since during co-firing local Al BSFs are induced at the location of these blisters. The best fill factors and short circuit currents are obtained in the case of (i) a hydrophobic pre-passivation cleaning, since it leads to a small density of larger blisters, and (ii) 10nm of Al2O3, where the blistering size still increases during firing thanks to additional out-gassing. There is an apparent gain in Jsc and Voc of, respectively, 1.3mA/cm2 and 5mV for the best random Al BSF cells compared to full Al BSF reference cells, because of better rear internal reflection and rear surface passivation. [Copyright &y& Elsevier]

Aim Retrieval of a minimum of 12 lymph nodes has been recommended for adequately staging a node-negative colorectal cancer (CRC). This study was designed to determine whether the extra effort expended to recover more nodes for histological examination improves the accuracy of staging. Method Pathology reports, histology worklists, and haematoxylin and eosin (H&E) slides of 334 CRC resections were reviewed. The total number of nodes and the number of positive nodes harvested from the first and additional searches were recorded for each patient. Results The number of nodes retrieved from the 334 resections at the first search ranged from 0 to 57 (mean: 14.2), with 195 patients (58.4%) having ≥ 12 nodes. Nodal metastasis was found in 122 (33.6%) patients. Additional searches were performed on 115 patients, including 91 with < 12 nodes. The mean number of nodes recovered in these patients increased significantly, from 9.1 to 14.2 ( P < 0.0001). Thirty-one additional positive nodes were found in 19 patients following the further searches, and 12 (63.2%) of the 19 patients were upstaged using the American Joint Committee on Cancer (AJCC) 6th edition (2002) staging criteria. The total number of nodes retrieved and the probability of obtaining ≥ 12 nodes correlated negatively with the age of the patient and the rectosigmoid location of the tumours, but positively with the specimen length, the pericolic/perirectal fat width, female gender and tumour size. Conclusion Although a number of patient and specimen variables influence the number of lymph nodes retrieved, our observations support the importance of a thorough search for nodes in CRC specimens in order to achieve accurate tumour staging. [ABSTRACT FROM AUTHOR]

Abstract: In this paper, the degradation of a GaN-on-Si based RF power amplifier is investigated by means of electrical characterization. The reliability issues identified during this work are clearly related to the high thermal resistance between the device and the heat sink, which causes gate-leakage current and output power degradation. Moreover, we have demonstrated a low cost thermal optimization approach by increasing the thermal dissipation area and reducing the device carrier thickness. Measurement results show that the saturated output power can be increased from 1W up to 5W without device degradation at 3.8GHz. [Copyright &y& Elsevier]

Abstract: In this work, the degradation of a GaN power amplifier (PA) integrated in a thin film multi-chip module (MCM-D) interconnect technology is investigated by means of DC and RF measurements. Failure analysis has demonstrated that improper thermal contact may cause the PA module performance degradation. Moreover, we have experimentally studied the thermal effects on the RF performance of MCM-D and low-temperature co-fired ceramic (LTCC) PAs. It shows that the device exhibits a higher output power density on a thinned MCM-D substrate than on an LTCC substrate with thermal vias, and also that the output power density can be further improved by reducing the heat spread distance between active devices and heat sink. [Copyright &y& Elsevier]

Abstract: In this work, the impact of 1000h thermal storage test at 325°C on the performance of gallium nitride high electron mobility transistors grown on Si substrates (GaN-on-Si HEMTs) is investigated. The extensive DC- and pulse-characterization performed before, during and after the stress did not reveal degradation on the channel conduction properties as well as formation of additional trapping states. The failure investigation has shown that only the gate and drain leakage currents were strongly affected by the high temperature storage test. The physical failure analysis revealed a Au inter-diffusion phenomenon with Ni at the gate level, resulting in a worsening of the gate–AlGaN interface. It is speculated that this phenomenon is at the origin of the gate and drain leakage current increasing. [Copyright &y& Elsevier]

Abstract: This paper presents a simple and robust process for fabrication of functional electrostatic RF-MEMS switching devices with lifetimes easily exceeding 108 cycles by unipolar actuation at 100Hz. The device implements a switchable air gap capacitor and is therefore not limited in lifetime by dielectric charging as opposed to contact-type capacitive switches implementing high-k dielectrics. Even though these switched air gap capacitors have a rather low capacitance ratio of around 5–6, they can still form adequate switching devices and RF-circuits by making use of properly designed transmission lines and when combined with high-Q inductors. Examples described include tunable notch band filters designed for the 2GHz and 20GHz range and a tunable stop band filter. The novelty of the proposed process is that it combines a sacrificial layer consisting of a single layer with a single dry etching step for the dimples which define the height of the air gap in the down-state. This air gap is switched by electrostatic actuation of a thick (7μm) electroplated nickel bridge structure. The device is realized in a 4 lithographic steps process with low complexity and high robustness. [Copyright &y& Elsevier]

Abstract: More than a decade of research in the field of thermal, motion, vibration and electromagnetic radiation energy harvesting has yielded increasing power output and smaller embodiments. Power management circuits for rectification and DC–DC conversion are becoming able to efficiently convert the power from these energy harvesters. This paper summarizes recent energy harvesting results and their power management circuits. [Copyright &y& Elsevier]