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We demonstrate devices and architectures enabling applications such as light detection and ranging (LiDAR) and optical switches, including dispersive optical phased array (OPA) architectures, a hybrid silicon nitride - lithium niobate on insulator (SiN - LNOI) optical phase modulator, and scalable architectures for optical switches., 2021 IEEE 17th International Conference on Group IV Photonics (GFP), December 7-10, 2021, Malaga, Spain

The Green Chemistry Initiative (GCI) is a student-led group founded in 2012 with the primary mission of promoting green chemistry education at the University of Toronto. In order to achieve this, the GCI’s activities have included undergraduate curriculum development, arrangement of an external speaker seminar series, and organization of an annual three-day symposium along with biweekly trivia challenges. To broaden education beyond the Department of Chemistry, a successful YouTube video campaign articulating the Twelve Principles of Green Chemistry in an accessible manner has also been undertaken (acquiring over 40,000 views), in addition to monthly blog posts and conference/outreach presentations. Descriptions of these activities are discussed in this paper, along with the resulting impact they have had. Through such efforts, undergraduate and graduate students are showing a growing understanding of the relevance of green chemistry in today’s world, with the GCI serving as a platform for similar groups to build upon across Canada., Green Chemistry Letters and Reviews, 12 (2)

Basing on multivariate statistical methods, text and sentiment analysis, and profitability analysis, a study is performed, with the aim to define the role of Community-based cooperatives in the development process of the inner areas of the Italian region of Molise. Census data, direct interviews data, and balance sheets data are employed to identify a new model of local development based on cooperative principles.

In this paper, we analyze six published algorithms that evaluate environmental and hazard impact green metrics. The methods are compared and contrasted on a common set of chemical reactions and synthesis plans. The relative greenness of four reaction procedures to prepare iron(II)oxalate dihydrate and three industrial preparations of aniline are examined. We also examine the organic syntheses preparations of 2,2-diethoxy-1-isocyanoethane, thiete 1,1-dioxide, and ethyl phenylcyanopyruvate that we previously evaluated by material efficiency. We discuss the merits and limitations of all algorithms with respect to quality of calculation outputs, visualization, and ease of use.

The ever-increasing demand for integrated, low power interconnect systems is pushing the bandwidth density of CMOS photonic devices. Taking advantage of the strong Franz-Keldysh effect in the C and L communication bands, electro-absorption modulators in Ge and GeSi are setting a new standard in terms of device footprint and power consumption for next generation photonics interconnect arrays. In this paper, we present a compact, low power electro-absorption modulator (EAM) Si/GeSi hetero-structure based on an 800 nm SOI overlayer with a modulation bandwidth of 56 GHz. The device design and fabrication tolerant process are presented, followed by the measurement analysis. Eye diagram measurements show a dynamic ER of 5.2 dB at a data rate of 56 Gb/s at 1566 nm, and calculated modulator power is 44 fJ/bit.

A detailed investigation examines how the size of allylbenzene-capped silicon nanocrystals (ncSi:AB) affects their chemical reactivity with gaseous O2, H2O, and O2/H2O as probed by in situ luminescence spectroscopy. Specifically, changes in the photoluminescence (PL) of size-separated ncSi:AB are monitored through alterations of their PL absolute quantum yield (AQY) as well as the wavelength and intensity of their PL spectra over time. These experiments, conducted under both continuous and intermittent illumination, help elucidate the roles of O2, H2O, and mixtures of O2/H2O, with respect to oxidation of ncSi:AB as a function of their size, providing vital information for any perceived application in advanced materials and biomedical devices.

The size-dependence of the absolute luminescence quantum yield of size-separated silicon nanocrystals reveals a "volcano" behavior, which switches on around 5 nm, peaks at near 3.7-3.9 nm, and decreases thereafter. These three regions respectively define: i) the transition from bulk to strongly quantum confined emissive silicon, ii) increasing confinement enhancing radiative recombination, and iii) increasing contributions favoring non-radiative recombination.

Here we describe for the first time the synthesis of colloidally stable, brightly luminescent perfluorodecyl-capped silicon nanocrystals and compare the properties of solutions and films made from them with those of their perhydrodecyl-capped relatives. The perfluorodecyl capping group compared to the perhydrodecyl capping group yields superior hydrophobicity and much greater resistance to air oxidation, the enhanced electron-withdrawing character induces blue shifts in the wavelength of photoluminescence, and the lower-frequency carbon-fluorine stretching modes disfavor non-radiative relaxation pathways and boost the absolute photoluminescence quantum yield. Together these attributes bode well for advanced materials and biomedical applications founded upon perfluorodecyl-protected silicon nanocrystals.

Objective: Veterans evaluated at the WRIISC present with multiple and chronic health conditions such as posttraumatic stress disorder (PTSD), pain, and fatigue. These patients often experience poor symptom relief. A pilot project was designed to determine whether such veterans would practice yoga as an adjunct to conventional medical care. We also used a range of standard screening measures to examine the health profile of individuals. Methods: Veterans were referred by VA clinicians to a WRIISC yoga clinic established in 2009. Two classes were offered per week. Veterans were assessed at baseline and after 12 classes with the PTSD Ch ecklist (PCL), Short F orm McGill Pain Questionnaire (SF-12), and the Flinders Fatigue Scale (FFS). Results: There have been 293 patient referrals so far and more than 1,824 yoga contact hours. Detailed data were collected on 10 veterans age 53–85 yrs (6 males). The screening instruments revealed nonsignificant benefits of yoga across the classes (p > .05). Furthermore, the PCL scores showed that four patients (40%) screened positive for PTSD (mean severity score = 40.9, range = 18–70). In addition, the PCL showed positive correlations with measures of pain (FS-12; Spearman’s rho = .76, p < .01), and chronic fatigue (FFS; Spearman’s rho = .94, p < .001). Similar results were found for equivalent correlations after 12 yoga classes. Conclusion: This pilot study demonstrates that veterans accept yoga as a complementary treatment to their regular medical care. Of possible significance is the observation that 40% of the patients screened positive for PTSD. The reasons for this are not clear but may be because such patients were referred at a higher rate. It is also possible that PTSD patients seek out yoga classes as an effective means of treating their symptoms. The strong correlations between measures of PTSD, pain, and fatigue suggest far-reaching implications for the integration of yoga in the treatment of veterans with a broad array of disorders exacerbated by stress. 2. Yoga-based Psychotherapy Group With Urban Youth Exposed to Trauma

Specific size, shape and surface chemistry influence the biological activity of nanoparticles. In the case of lipophilic nanoparticles, which are widely used in consumer products, there is evidence that particle size and formulation influences skin permeability and that lipophilic particles smaller than 6 nm can embed in lipid bilayers. Since most nanoparticle synthetic procedures result in mixtures of different particles, post-synthetic purification promises to provide insights into nanostructure-function relationships. Here we used size-selective precipitation to separate lipophilic allyl-benzyl-capped silicon nanoparticles into monodisperse fractions within the range of 1 nm to 5 nm. We measured liposomal encapsulation and cellular uptake of the monodisperse particles and found them to have generally low cytotoxicities in Hela cells. However, specific fractions showed reproducibly higher cytotoxicity than other fractions as well as the unseparated ensemble. Measurements indicate that the cytotoxicity mechanism involves oxidative stress and the differential cytotoxicity is due to enhanced cellular uptake by specific fractions. The results indicate that specific particles, with enhanced suitability for incorporation into lipophilic regions of liposomes and subsequent in vitro delivery to cells, are enriched in certain fractions.

Background: Neurofibrillary tangles and senile plaques are hallmarks of Alzheimer’s disease (AD) although the molecular basis of their coexistence remains elusive. The peptidyl-prolyl cis/trans isomerase Pin1 acts on both tau and amyloid precursor protein to regulate their functions by influencing tau phosphorylation and amyloid precursor protein processing. Objective: In order to identify potential biomarkers for AD in easily accessible cells and to gain insight into the relationship between the brain and peripheral compartments in AD pathology, we investigated Pin1 expression and activity in the peripheral blood mononuclear cells of subjects with late-onset AD (LOAD) and age-matched controls (CT). Methods: Gene and protein expression, promoter methylation, Ser16 phosphorylation and activity of Pin1 were evaluated in 32 samples from subjects with LOAD and in 28 samples from CT. Results: In LOAD subjects, there was a statistically significant reduction in Ser16 phosphorylation (–30%; p = 0.041) and promoter methylation (–8%; p = 0.001), whereas Pin1 expression was significantly increased (+74%; p = 0.018). Conclusion: The modifications of Pin1 found in LOAD subjects support its involvement in the pathogenesis of the disease with an important role being played by epigenetic mechanisms.

The role of ethylene in promoting metathesis of acetylenic enynes is probed within the context of ring-closing enyne metathesis, using first- and second-generation Grubbs catalysts. Under inert atmosphere, rapid catalyst deactivation is observed by calibrated GC-FID analysis for substrates with minimal propargylic bulk. MALDI-TOF mass spectra reveal a Ru(enyne)(2) derivative that exhibits very low reactivity toward both enyne and ethylene. Under ethylene, formation of this species is suppressed. Enynes with bulky propargylic groups are not susceptible to this catalyst deactivation pathway, even under N(2) atmosphere.

We report the preparation of monodisperse silicon nanocrystals (ncSi) by size-separation of polydisperse alkyl-capped ncSi using organic density gradient ultracentrifugation. The ncSi were synthesized by thermal processing of trichlorosilane-derived sol-gel glasses followed by HF etching and surface passivation with alkyl chains and were subsequently fractionated by size using a self-generating density gradient of 40 wt % 2,4,6-tribromotoluene in chlorobenzene. The isolated monodisperse fractions were characterized by photoluminescence spectroscopy and high-angle annular dark-field scanning transmission electron microscopy and determined to have polydispersity index values between 1.04 and 1.06. The ability to isolate monodisperse ncSi will allow for the quantification of the size-dependent structural, optical, electrical, and biological properties of silicon, which will undoubtedly prove useful for tailoring property-specific optoelectronic and biomedical devices.

In the last two decades, the child welfare system has undergone a series of dramatic changes. We have moved from a broad concern for the social welfare of children and families to a restricted focus on detecting, investigating and assessing instances of child physical and sexual abuse and neglect. Spiraling reports of suspected or actual abuse and neglect, higher caseloads, reduced resources and lack of support for both families and workers, have all contributed to narrowing the focus of contemporary child welfare to one more aptly characterized as child protection. Child protection discourse is concerned with the nature and extent of state intervention into family life for the purpose of protecting children at risk of harm. While much attention has been given to boundaries and procedures for state intervention, it is less common to critically examine the actual activities involved in protection of children. An exception to this is the feminist scholarship on the topic, illustrating that protection is ver...

Hydrosilylation kinetics of hydride-capped silicon nanocrystals with 1-decene are reported for the first time. In a side-by-side comparison, it is found that microwave heating has no evident acceleration effect on the hydrosilylation rate relative to conventional thermal heating.

Nanomaterials are becoming increasingly widespread in consumer technologies, but there is global concern about the toxicity of nanomaterials to humans and the environment as they move rapidly from the research laboratory to the market place. With this in mind, it makes sense to intensify the nanochemistry community's global research effort on the synthesis and study of nanoparticles that are purportedly "green". One potentially green nanoparticle that seems to be a most promising candidate in this context is silicon, whose appealing optical, optoelectronic, photonic, and biomedical attributes are recently gaining much attention. In this paper, we outline some of our recent contributions to the development of the growing field of silicon nanocrystals (ncSi) in order to stress the importance of continued study of ncSi as a green alternative to the archetypal semiconductor nanocrystals like CdSe, InAs, and PbS. While a variety of developments in synthetic methods, characterization techniques, and applications have been reported in recent years, the ability to prepare colloidally-stable monodisperse ncSi samples may prove to have the largest impact on the field, as it opens the door to study and access the tunable size-dependent properties of ncSi. Here, we summarize our recent contributions in size-separation methods to achieve monodisperse samples, the characterization of size-dependant property trends, the development of ncSi applications, and their potential impact on the promising future of ncSi.

Nanomaterials are becoming increasingly widespread in consumer technologies, but there is global concern about the toxicity of nanomaterials to humans and the environment as they move rapidly from the research laboratory to the market place. With this in mind, it makes sense to intensify the nanochemistry community's global research effort on the synthesis and study of nanoparticles that are purportedly "green". One potentially green nanoparticle that seems to be a most promising candidate in this context is silicon, whose appealing optical, optoelectronic, photonic, and biomedical attributes are recently gaining much attention. In this paper, we outline some of our recent contributions to the development of the growing field of silicon nanocrystals (ncSi) in order to stress the importance of continued study of ncSi as a green alternative to the archetypal semiconductor nanocrystals like CdSe, InAs, and PbS. While a variety of developments in synthetic methods, characterization techniques, and applications have been reported in recent years, the ability to prepare colloidally-stable monodisperse ncSi samples may prove to have the largest impact on the field, as it opens the door to study and access the tunable size-dependent properties of ncSi. Here, we summarize our recent contributions in size-separation methods to achieve monodisperse samples, the characterization of size-dependant property trends, the development of ncSi applications, and their potential impact on the promising future of ncSi.

The synthesis of highly luminescent, colloidally-stable and organically-capped silicon nanocrystals (ncSi) and their incorporation into a visible wavelength organic light-emitting diode (OLED) is reported. By substituting decyl chains with aromatic allylbenzene capping ligands and size-selecting visible emitting ncSi, superior packing density, enhanced charge transport, and an improved photoluminescence absolute quantum yield of the ncSi is obtained in the active layer of an OLED.

Size-selective precipitation was used to successfully separate colloidally stable allylbenzene-capped silicon nanocrystals into several visible emitting monodisperse fractions traversing the quantum size effect range of 1–5 nm. This enabled the measurement of the absolute quantum yield and lifetime of photoluminescence of allylbenzene-capped silicon nanocrystals as a function of size. The absolute quantum yield and lifetime are found to monotonically decrease with decreasing nanocrystal size, which implies that nonradiative vibrational and surface defect effects overwhelm spatial confinement effects that favor radiative relaxation. Visible emission absolute quantum yields as high as 43% speak well for the development of “green” silicon nanocrystal color-tunable light emitting diodes that can potentially match the performance of their toxic heavy metal chalcogenide counterparts.

Adenosine suppresses immune responses through the A2Areceptor (A2AR). This study investigated the interleukin 10 (IL-10) genetic profile and the expression of A2AR in peripheral blood mononuclear cells (PBMCs) of patients with mild cognitive impairment (MCI), Alzheimer disease (AD), and age-matched controls to verify, if they may help distinguish different forms of cognitive decline. We analyzed the IL-10 genotype and the expression of A2AR in 41 subjects with AD, 10 with amnestic MCI (a-MCI), 49 with multiple cognitive domain MCI (mcd-MCI), and 46 controls. There was a significant linear increase in A2AR mRNA levels and A2AR density from mcd-MCI to a-MCI, with intermediate levels being found in AD. The IL-10 AA genotype frequency was 67% in a-MCI, 46% in AD, 35% in mcd-MCI, and 20% in controls. These data suggest that the assessment of the IL-10 genotype and the expression of A2AR in PBMCs may be a valuable means of differentiating between a-MCI and mcd-MCI.

Specific proinflammatory alleles are associated with higher risk of Alzheimer disease (AD) in different onset age. The homozygosis for the A allele of −1082 polymorphism (G/A) of interleukin-10 (IL-10) promotes a higher risk of AD and reduced IL-10 generation in peripheral cells after amyloid stimulation. In this paper we analysed genotype and allele frequencies of this polymorphism in 138 subjects with mild cognitive impairment (MCI) diagnosed, respectively, as amnestic (a-MCI) and multiple impaired cognitive domains (mcd-MCI). The genotype frequencies were similar in a-MCI and AD subjects, whereas in mcd-MCI comparable to controls (AA genotype: 50% in a-MCI, 49.2% in AD, 28.7% in mcd-MCI and 31.8% in controls). Consequently, both allele and genotype distributions were significantly different between a-MCI and mcd-MCI (allele: 𝑃 = . 0 2 , genotype: 𝑃 < . 0 5 ). These results support the theory that polymorphisms of cytokine genes can affect neurodegeneration and its clinical progression. IL-10 may partly explain the conversion of a-MCI to AD or be a genetic marker of susceptibility.

Futaleufu hydropower plant has 4 Francis turbines rated 118 MW and it is connected to the power system by 2times330 kV lines. Studies carried out in the past did not predict the instable operation of Futaleufu after a 330 kV line fault, when some Futaleufu turbines are automatically disconnected as a consequence of the faulted line tripping. Load rejection caused by disconnected turbines generate large transients in the remaining turbines due to hydraulic coupling through the common conduits. Then, to improve related models and, therefore, to improve studies results of such a line fault it was necessary to make several tests in Futaleufu power plant. Finally, these models were used to conduct studies to design a new automatism, like the gate partial closing of the remaining turbines, to obtain a dynamically stable operation of Futaleufu after the disconnection by fault of a line of 330 kilovolts.

The balance between T helper (h)1 and Th2 responsiveness seems to represent a key event in the evolution of hepatitis C virus (HCV) infection. In particular, Th1 cytokines [interleukin (IL-2) and interferon (IFN-gamma)] have been demonstrated to mediate the antiviral immune response. Serum levels of Th1 cytokines (IL-2 and IFN-gamma) as well as of Th2 products (IL-4 and IL-10) were determined in a group of HCV-positive patients before and after treatment with IFN-alpha and Ribavirin (RIB). Results indicate that responder patients exhibited increased levels of IFN-gamma and IL-10, while this enhancement was not observed in non-responder patients. In this respect, the major effect exerted by the combined therapy with IFN-alpha/RIB could be represented by the attainment of a re-equilibrium between inflammatory (Th1) and antiinflammatory (Th2) mechanisms. In this framework, according to current literature, novel therapeutical approaches to treat HCV infection are represented by administration of recombinant IL-2 and IL-10.

Between April, 1992 and December, 1995, forty consecutive patients with a cerebral malignant glioma (WHO Grade III and IV) were enrolled in a trial consisting in surgery and post-operative administration of radiotherapy (4500-6000 cGy), carboplatin (CBDCA; dose of 450-600 mg/m2), and oral tamoxifen (TAM; at doses of 40, 80 or 120 mg/day). Two patients of the TAM group died in the postoperative period from a pulmonary embolism and myocardial infarction, respectively. The patients (all dosages combined) had a median survival time of 13 months from the time of diagnosis. The 12-month and 24-month survival rates were 52% and 32%, respectively. The median relapse-free survival time was 7 months. Patients treated with higher doses of TAM (80-120 mg/day) demonstrated a longer median survival rate (13 months both) and a longer 12-month survival result (58% and 76%, respectively). Patients who assumed TAM for a period longer than 3 months (group +3) have a higher median survival rate (16 months) and better 12-month and 24-month results (62% and 40%, respectively). Moreover, the median relapse-free survival time was 10 months (versus 6 months in group -3; p = 0.0038). However, it is not possible to exclude that patients of group +3 had a slower growing or a stable tumor and were well enough to assume TAM for a longer period. The results observed in the TAM-group have been compared with those of 40 matched controls treated with surgery, radiotherapy and CBDCA. These patients had a median survival time of 9 months (p = 0.04) and the 12-month and 24-month survival rates were 30% and 0%, respectively. The median relapse-free survival time was 4 months (p = 0.0014). These data suggest a potential role for combinational TAM-CBDCA therapy in the post-operative treatment of cerebral malignant gliomas; further clinical phase III trials, especially those with higher dosages of TAM are warranted.

The case of a patient with a right atypical trigeminal neuralgia caused by a metastatic tumor involving the Meckel's cave is reported. His medical history was significant for colon-rectal adenocarcinoma. The preoperative diagnosis of Meckel's cave neoplasm was made by MR. The patient underwent surgery, consisting of total removal of tumor and peeling of the ganglion and of the branches of the nerve, obtaining a histological diagnosis and a resolution of pain. The clinical, radiological findings and the treatment of this rare entity are discussed.

Abnormal fibrinolysis and thrombotic complications have been often observed in patients who had undergone surgery for meningioma. Fourteen patients, affected by meningioma, were studied before surgery, during surgery and 24 h after surgery in order to evaluate the modifications of the fibrinolysis system and the coagulation physiological inhibitors. Before surgery, no patient showed hyperfibrinolysis and/or modifications of coagulation physiological inhibitors. During surgery, an activation of fibrinolysis with pathological levels of tissue plasminogen activator activity (x = 6.33 U/dl, SD = 7.9, p = 0.02) and increased levels of fibrin degradation products (x = 0.21, SD = 0.18, p = 0.002) was noted. Modifications of the fibrinolysis parameters occurred only in 9/14 patients (64%). These patients presented a more vascularized tumour, revealed before surgery by computerized tomography scan and cerebral arteriography and directly confirmed during the resection. Twenty-four hours after surgery no patient presented fibrinolysis activation. There was no evidence of disseminated intravascular coagulation in our patients. None of them presented pathological decrease of the physiological coagulation inhibitors or thrombotic complications. In conclusion, during surgery, fibrinolysis parameters show important modifications in patients with vascularized meningioma suggesting an ongoing tumour-host interaction. These variations must be taken in account, in order to plan timely a correct therapeutic approach.

The general availability of cerebral computed tomographic and magnetic resonance imaging scans makes the observation of symptomatic intracranial meningiomas in very elderly patients (aged 80 yr or more) relatively frequent. A few authors have reported on patients who have undergone surgery for intracranial meningiomas in their 9th decade of life, without providing indications regarding the surgical criteria and the prognostic factors. We report on a series of 17 patients who have received surgery for intracranial meningiomas in their 9th decade of life, with the goal of determining some surgical criteria for general physicians and neurosurgeons. Patients with severe systemic disease and definite functional limitations (American Society of Anesthesiology Class III) had a major postoperative morbidity (P = 0.020) and mortality (P = 0.005), especially if they scored low (70) on the preoperative Karnofsky Rating Scale (P = 0.010). The risk of postoperative morbidity was higher when the maximum diameter of the tumor was5 cm (P = 0.031).

Of 144 cases of pituitary adenoma operated on in the period 1981-1985, 53 underwent angiography and two of these had an associated intracranial aneurysm. The aetiological hypotheses are viewed in the light of these two cases and of the 60 published cases of this association. The most convincing hypotheses involve mechanical, microcirculatory and hormonal factors. On the hormonal front, GH seems to have a predisposing influence on intracranial aneurysm formation.

Previous research on long-term memory has shown that the number of items retrieved is a power function of the number presented. An application of this power law to the prediction of anagram solution times as a function of word length was, in general, successful. It was also found that giving semantic cues decreased solution time more than did giving graphemic cues.

A simple surgical procedure for the repair of cerebrospinal otorrhoea using human fibrin glue has proved safe and successful in two patients with post-surgical fistula. The procedure, which requires only mild sedation, is recommended for open or closed cerebrospinal otorrhoea accompanied by severe neurosensory hearing loss, as long as the fistula has not been caused by chronic inflammatory processes or given rise to intracranial infectious complications.

Of 144 cases of pituitary adenoma operated on in the period 1981-1985, 53 underwent angiography and two of these had an associated intracranial aneurysm. The aetiological hypotheses are viewed in the light of these two cases and of the 60 published cases of this association. The most convincing hypotheses involve mechanical, microcirculatory and hormonal factors. On the hormonal front, GH seems to have a predisposing influence on intracranial aneurysm formation.

Twenty-two cases of unusual intracranial meningioma associated with a cyst are reported and 144 published cases reviewed. The complex mechanisms leading to the formation of the cyst within the meningioma are analyzed on the basis of the surgical and histopathological evidence. The neuroradiological features (Computed Tomography and Angiography) which supply a correct preoperative diagnosis are discussed. It is clear from the literature how difficult preoperative diagnosis is, being possible only in 38% of cases with CT scanning and in 13% with angiography. It is necessary to remove not only the solid portion of the meningioma but also the cyst wall in order to prevent a recurrence. This is technically difficult for the type II intratumoural variety of Nauta's classification.