N,N-Dimethyl-4-amino-2,1,3-benzothiadiazole: Synthesis and Luminescent Solvatochromism

N,N-Dimethyl-4-amino-2,1,3-benzothiadiazole (BTDNMe2) was synthesized from the commercially available 2,1,3-benzothiadiazole (BTD) by nitration in a sulfonitric mixture, followed by a reduction of the nitro group and subsequent methylation with iodomethane. BTDNMe2 was fully characterized by means of nuclear magnetic resonance (NMR) and infrared spectroscopy. The solutions of BTDNMe2 in common organic solvents revealed to be appreciably luminescent in the visible range. The electronic transitions related to the absorption and emission properties were associated with the HOMO–LUMO energy gap by means of electrochemical measurements and DFT calculations. Finally, BTDNMe2 was successfully used to prepare luminescent-doped poly(methyl methacrylate) samples

N,N-dimethyl-4-amino-2,1,3-benzothiadiazole: synthesis and luminescent solvatochromism

2,1,3-benzothiadiazole (BTD) derivatives were widely applied as herbicides, fungicides and antibacterial agents. The strong withdrawing ability of BTD and its fluorescent properties make it appealing also for the preparation of luminescent materials. Polymers containing the BTD fragment were successfully exploited for advances applications such as organic light-emitting diodes (OLEDs), dyes, solar and photovoltaic cells, as recently reported by B.A.D. Neto et al. [Eur. J. Org. Chem. (2013) 228]. To the best of our knowledge, a complete synthetic procedure for N,N-dimethyl-4-amino-2,1,3-benzothiadiazole (BTDNMe2) from the commercially available 2,1,3-benzothiadiazole was never reported. The only reference available dates back to 1976 and describes the thermal decomposition of the corresponding ammonium salt [N.M. Slavachevskaja et al., Pharm. Chem. J. 10 (1976) 327]. The synthetic route here proposed involves nitration of BTD in sulfonitric mixture, followed by reduction of the nitro-group and subsequent methylation with iodomethane. BTDNMe2 was isolated as dark red oil and it was fully characterized by means of nuclear magnetic resonance (NMR) and infrared spectroscopy. Solutions of BTDNMe2 in common organic solvents revealed to be appreciably luminescent in the visible range. The increase of dielectric constant caused a non-linear red shift of the absorption and emission maxima, an increase of the Stokes shift and a reduction of the photoluminescence quantum yield. The electronic transitions related to the absorption and emission properties were associated to the HOMO-LUMO energy gap by means of electrochemical measurements and DFT calculations. Finally, BTDNMe2 was successfully used for the preparation of luminescent doped polymethylmethacrylate samples with intense orange emission

Valutazione di schemi di trasmissione basati su SR-ARQ

Questa tesi propone uno studio di alcune tecniche di correzione degli errori, basate sul meccanismo Selective Repeat – Automatic Repeat reQuest (SR-ARQ), per analizzare le prestazioni degli schemi, con particolare riferimento al caso di lunghi tempi di propagazione. Mettiamo a confronto l’SR-ARQ con 2 varianti dello stesso, Double Selective Repeat (2SR-ARQ) e Second Replica Selective Repeat (SR2-ARQ). Facciamo così uno studio approssimato sul ritardo medio di consegna (delivery delay, mdelay) di un pacchetto in particolare, quello centrale rispetto a una finestra di larghezza m slots (spazi). La valutazione si basa su uno studio analitico originale, nel quale vengono ricavati risultati numerici che vengono discussi e illustrat

Analisi della resistenza di strutture in lega leggera saldata con effetto del trattamento termico post saldatura

Nel documento si sono indagati gli effetti di un trattamento termico effettuato dopo la saldatura di leghe di alluminio al fine di migliorare le proprietà meccaniche dei giunti saldati. Si sono svolte delle prove sperimentali in modo da quantificare tali miglioramenti e si sono applicati i risultati ottenuti alla ottimizzazione di una struttura in alluminio già esistent

Intense millisecond-long red luminescence from heteroleptic Cu(I) 2,1,3-benzothiadiazole complexes

Intense red-emitting heteroleptic Cu(I) complexes were isolated using 2,1,3-benzothiadiazole (BTD) as N-donor ligand and triphenylphosphine, bis[(2-diphenylphosphino)phenyl] ether (DPEphos) or bis(diphenylphosphino)methane (dppm) as P-donors. The structures of two mononuclear and one dinuclear derivatives with one nitrogen and two phosphorus atoms in the Cu(I) coordination sphere were ascertained by means of X-ray diffraction, revealing an overall tetrahedral geometry at the solid state due to the direct interaction of the counterion with Cu(I). Upon excitation with UV and violet-blue light, the Cu(I) complexes exhibited emissions centred between 623 and 683 nm with photoluminescence quantum yields up to 46%. Lifetimes in the tens-thousands millisecond range were observed. The values resulted affected by the choice of the counterion, and an increase of up to 15% was observed passing from tetrafluoroborate to perchlorate in the mononuclear BTD complex with two PPh3 ligands. DFT calculations indicated that the lowest energy absorptions have charge transfer nature, from the {CuP2} fragments with the contributions of the P-bonded aryl substituents to an unoccupied π* orbital of BTD. The triplet→singlet emissions involve the metal centre, the phosphine ligands, and the occupied and empty orbitals of BTD

Validation of the Norwegian pain sensitivity questionnaire

Background and purpose: There is a large variation in people’s reactions to painful stimuli. Although some conditions are more painful, the variation between people is larger than the reaction to pain across conditions. Induced experimental pain is one way to assess some aspects of these differences in pain perception. Experimental nociceptive testing is time consuming and not always feasible in a clinical setting. In order to overcome the obstacles of assessing pain sensitivity using experimental stimulation, the Pain Sensitivity Questionnaire (PSQ) was developed. The purpose of this study is to validate the Norwegian version of the PSQ. Methods: Construct validity was examined through an exploratory principal component factor analysis with varimax rotation. Internal consistency was measured by Cronbach’s alpha reliability for subscales and the total PSQ. As confounding variables such as age and gender may contribute to the experience of pain, a regression analysis was performed with demographic variables and PSQ scores as independent variables and the experimental measures of pain as the dependent variable. Results: The factor analysis yielded at two factor solution, with an eigenvalue greater than one, explain 58% of the variance. Cronbach’s alpha for the PSQ was 0.92. In the regression analysis, only PSQ scores contributed to explain the experimental pain intensity and tolerance. Gender only influenced the experimental pain threshold, as men had statistically significant higher heat pain threshold than women. Conclusion: This study shows that PSQ is a valid and reliable questionnaire and might be a promising instrument for assessing pain sensitivity in Norwegian clinical settings. Further studies are needed to examine whether the PSQ can be used in clinical settings to predict postoperative pain and the development of chronic pain

Odontostomatological Traits in North-Eastern Italy’s Isolated Populations: An Epidemiological Cross-Sectional Study

Malocclusions and temporomandibular disorders (TMDs) are oral health problems that are spread worldwide. To date, few studies focused on their prevalence and associated risk factors are available. This study aims to define the prevalence and distribution of odontostomatological traits and evaluate specific risk factors in isolated villages in north-eastern Italy, taking advantage of their environmental homogeneity. Nine hundred and forty-four participants aged six to eighty-nine years were enrolled. Thirty-one odontostomatological phenotypes, classified into five domains (airways, bad habits, extraoral and intraoral parameters, TMDs, and teeth), were evaluated. A descriptive statistical analysis was performed; mixed logistic models were used to test the relationships among the traits. According to the study’s findings, Angle’s class I was prevalent (65.3%) followed by class II malocclusion (24.3%); class III and reversed overjet were the least frequent malocclusions (10.4% and 1.8%, respectively). Temporomandibular joint (TMJ) click/noise was prevalent among TMDs (34.7%). The statistically significant (p-value < 0.05) risk factors were ankyloglossia for phonetic issues (OR 1.90) and bruxism for TMJ click/noise (OR 1.70) and pain (OR 2.20). Overall, this work provides a picture of the prevalence of malocclusions and TMDs in a large Italian sample and reveals risk factors to take into account in the development of preventive strategies and treatments

The effects of passive leg raising may be detected by the plethysmographic oxygen saturation signal in critically ill patients

Abstract Background A passive leg raising (PLR) test is positive if the cardiac index (CI) increased by > 10%, but it requires a direct measurement of CI. On the oxygen saturation plethysmographic signal, the perfusion index (PI) is the ratio between the pulsatile and the non-pulsatile portions. We hypothesised that the changes in PI could predict a positive PLR test and thus preload responsiveness in a totally non-invasive way. Methods In patients with acute circulatory failure, we measured PI (Radical-7) and CI (PiCCO2) before and during a PLR test and, if decided, before and after volume expansion (500-mL saline). Results Three patients were excluded because the plethysmography signal was absent and 3 other ones because it was unstable. Eventually, 72 patients were analysed. In 34 patients with a positive PLR test (increase in CI ≥ 10%), CI and PI increased during PLR by 21 ± 10% and 54 ± 53%, respectively. In the 38 patients with a negative PLR test, PI did not significantly change during PLR. In 26 patients in whom volume expansion was performed, CI and PI increased by 28 ± 14% and 53 ± 63%, respectively. The correlation between the PI and CI changes for all interventions was significant (r = 0.64, p  9%, a positive response of CI (≥ 10%) was diagnosed with a sensitivity of 91 (76–98%) and a specificity of 79 (63–90%) (area under the receiver operating characteristics curve 0.89 (0.80–0.95), p < 0.0001). Conclusion An increase in PI during PLR by 9% accurately detects a positive response of the PLR test. Trial registration ID RCB 2016-A00959-42. Registered 27 June 2016

MOESM1 of Carotid and femoral Doppler do not allow the assessment of passive leg raising effects

Additional file 1: Table S1. Ability of different Doppler variable to detect a positive passive leg raising test. Table S2. Diagnostic ability of changes in carotid and femoral blood flows to detect changes in cardiacindex ≥ 10% and ≥ 15%. Figure S1. Study design. Figure S2. Correlation between absolute values of carotid blood flow (measured by TAMEAN) and of cardiac index, n = 135 (n = 38 before PLR, 38 during passive leg raising (PLR), 38 after PLR and 21 after volume expansion = 135 in total). Figure S3. Correlation between absolute values of femoral blood flow and of cardiac index, n = 45 ( n = 14 before PLR, 14 during passive leg raising (PLR), 14 after PLR and 3 after volume expansion = 45 in total)