Optical and electrical measurements on UV sensitive photodiodes

The optical and electrical characteristics of the various types of photodiodes potentially useful for UV radiometers were studied. It was concluded that both GaAsP and GaP photodiodes have advantages over silicon photodiodes in terms of spectral response and UV stability. Both GaAsP and GaP have excellent electrical characteristics for low frequency radiometers, although their high capacitance could be inconvenient for high frequency applications. GaAsP is particularly good with respect to dynamic range

Review of \u3ci\u3eDivining Margaret Laurence: A Study of Her Complete Writings\u3c/i\u3e By Nora Foster Stovel

Neil Besner is right to judge Nora Foster Stovel\u27s Divining highly: it ranges across all of Laurence\u27s work ... intelligently and accessibly, as he says on the jacket. Before I augment his praise I must note a couple of blemishes, if Stovel will accept the soft impeachment of an admirer. Malcolm Ross did not teach the future Margaret Laurence or anyone else at United College (now the University of Winnipeg): I was a student with Peggy Wemyss in Ross\u27s stunning Seventeenth-Century Thought on the Fort Garry campus of the University of Manitoba (and in spite of the uncorrected typo of photo #18, following p. 124, of my Alien Heart: The Life and Work of Margaret Laurence [2003]). More serious, Stovel repeats Donez Xiques\u27s misreading (in Margaret Laurence: The Making of a Writer [2005]) of Laurence\u27s early and impressive poem Pagan Point, where one notes the evident opposition of the unearthly paganism of Old Neptune ... and the ancient battle-voice of Thor to what replaced them. Peggy\u27s pagan gods are associated with the cry, / raucous and heathen, of a far-off loon, anticipating the loons heard by Piquette in A Bird in the House. Piquette belongs to the family Tonnerre (some Canadiens recognize that as the family of Thor) and might have been the only one, after all, who had heard the crying of the loons, also heard by Allie Chorniuk in Dance on the Earth who thinks but tonight their voices are silent -Homo sapiens is driving them away from the lakes, or killing them off . .. The thought ... hurts unbearably (quoted in Alien Heart, 449). The opposition here (which Stovel discerns) is also that of Pagan Point : the raucous and heathen loon versus the dim cathedral-full of rest, .... where Man may [sic] find his God. This is like the opposition to Tennyson\u27s meek and mild Lotos Eaters posed by Ulysses, whose aim was echoed in the motto of Peggy Wemyss\u27s high school: To strive, to seek, to find, and not to yield. The attitude of Blake ( Was Jesus gentle ... ? ), was familiar as well to Hagar\u27s creator. This misreading is almost as regrettable as identifying Henry James\u27s definition of the novel as a loose, baggy monster (Divining, 247), a phrase James used in his preface to The Tragic Muse as a critique of certain novels, not as a definition of the genre

Review of \u3ci\u3eDivining Margaret Laurence: A Study of Her Complete Writings\u3c/i\u3e By Nora Foster Stovel

Neil Besner is right to judge Nora Foster Stovel\u27s Divining highly: it ranges across all of Laurence\u27s work ... intelligently and accessibly, as he says on the jacket. Before I augment his praise I must note a couple of blemishes, if Stovel will accept the soft impeachment of an admirer. Malcolm Ross did not teach the future Margaret Laurence or anyone else at United College (now the University of Winnipeg): I was a student with Peggy Wemyss in Ross\u27s stunning Seventeenth-Century Thought on the Fort Garry campus of the University of Manitoba (and in spite of the uncorrected typo of photo #18, following p. 124, of my Alien Heart: The Life and Work of Margaret Laurence [2003]). More serious, Stovel repeats Donez Xiques\u27s misreading (in Margaret Laurence: The Making of a Writer [2005]) of Laurence\u27s early and impressive poem Pagan Point, where one notes the evident opposition of the unearthly paganism of Old Neptune ... and the ancient battle-voice of Thor to what replaced them. Peggy\u27s pagan gods are associated with the cry, / raucous and heathen, of a far-off loon, anticipating the loons heard by Piquette in A Bird in the House. Piquette belongs to the family Tonnerre (some Canadiens recognize that as the family of Thor) and might have been the only one, after all, who had heard the crying of the loons, also heard by Allie Chorniuk in Dance on the Earth who thinks but tonight their voices are silent -Homo sapiens is driving them away from the lakes, or killing them off . .. The thought ... hurts unbearably (quoted in Alien Heart, 449). The opposition here (which Stovel discerns) is also that of Pagan Point : the raucous and heathen loon versus the dim cathedral-full of rest, .... where Man may [sic] find his God. This is like the opposition to Tennyson\u27s meek and mild Lotos Eaters posed by Ulysses, whose aim was echoed in the motto of Peggy Wemyss\u27s high school: To strive, to seek, to find, and not to yield. The attitude of Blake ( Was Jesus gentle ... ? ), was familiar as well to Hagar\u27s creator. This misreading is almost as regrettable as identifying Henry James\u27s definition of the novel as a loose, baggy monster (Divining, 247), a phrase James used in his preface to The Tragic Muse as a critique of certain novels, not as a definition of the genre

Review of \u3ci\u3eDivining Margaret Laurence: A Study of Her Complete Writings\u3c/i\u3e By Nora Foster Stovel

Neil Besner is right to judge Nora Foster Stovel\u27s Divining highly: it ranges across all of Laurence\u27s work ... intelligently and accessibly, as he says on the jacket. Before I augment his praise I must note a couple of blemishes, if Stovel will accept the soft impeachment of an admirer. Malcolm Ross did not teach the future Margaret Laurence or anyone else at United College (now the University of Winnipeg): I was a student with Peggy Wemyss in Ross\u27s stunning Seventeenth-Century Thought on the Fort Garry campus of the University of Manitoba (and in spite of the uncorrected typo of photo #18, following p. 124, of my Alien Heart: The Life and Work of Margaret Laurence [2003]). More serious, Stovel repeats Donez Xiques\u27s misreading (in Margaret Laurence: The Making of a Writer [2005]) of Laurence\u27s early and impressive poem Pagan Point, where one notes the evident opposition of the unearthly paganism of Old Neptune ... and the ancient battle-voice of Thor to what replaced them. Peggy\u27s pagan gods are associated with the cry, / raucous and heathen, of a far-off loon, anticipating the loons heard by Piquette in A Bird in the House. Piquette belongs to the family Tonnerre (some Canadiens recognize that as the family of Thor) and might have been the only one, after all, who had heard the crying of the loons, also heard by Allie Chorniuk in Dance on the Earth who thinks but tonight their voices are silent -Homo sapiens is driving them away from the lakes, or killing them off . .. The thought ... hurts unbearably (quoted in Alien Heart, 449). The opposition here (which Stovel discerns) is also that of Pagan Point : the raucous and heathen loon versus the dim cathedral-full of rest, .... where Man may [sic] find his God. This is like the opposition to Tennyson\u27s meek and mild Lotos Eaters posed by Ulysses, whose aim was echoed in the motto of Peggy Wemyss\u27s high school: To strive, to seek, to find, and not to yield. The attitude of Blake ( Was Jesus gentle ... ? ), was familiar as well to Hagar\u27s creator. This misreading is almost as regrettable as identifying Henry James\u27s definition of the novel as a loose, baggy monster (Divining, 247), a phrase James used in his preface to The Tragic Muse as a critique of certain novels, not as a definition of the genre

Stop, think SCORTCH: rethinking the traditional 'TORCH' screen in an era of re-emerging syphilis

BACKGROUND: The epidemiology of congenital infections is ever changing, with a recent resurgence in syphilis infection rates seen in the UK. Identification of congenital infection is often delayed; early recognition and management of congenital infections is important. Testing modalities and investigations are often limited, leading to missed diagnostic opportunities. METHODS: The SCORTCH (syphilis, cytomegalovirus (CMV), 'other', rubella, toxoplasmosis, chickenpox, herpes simplex virus (HSV) and blood-borne viruses) acronym increases the awareness of clinicians to the increased risk of congenital syphilis, while considering other infectious aetiologies including: zika, malaria, chagas disease, parvovirus, enterovirus, HIV, hepatitis B and C, and human T-lymphotropic virus 1, in addition to the classic congenital infections recognised in the 'TORCH screen' (toxoplasmosis, 'other', rubella, CMV, HSV). The SCORTCH diagnostic approach describes common signs present in infants with congenital infection, details serological testing for mother and infant and important direct diagnostics of the infant. Direct diagnostic investigations include: radiology, ophthalmology, audiology, microbiological and PCR testing for both the infant and placental tissue, the latter also warrants histopathology. CONCLUSION: The traditional 'TORCH screen' focuses on serology-specific investigations, often omits important direct diagnostic testing of the infant, and fails to consider emerging and re-emerging congenital infections. In recognition of syphilis as a re-emerging pathogen and the overlapping clinical presentations of various infectious aetiologies, we advocate for a broader outlook using the SCORTCH diagnostic approach

Precise multimodal optical control of neural ensemble activity.

Understanding brain function requires technologies that can control the activity of large populations of neurons with high fidelity in space and time. We developed a multiphoton holographic approach to activate or suppress the activity of ensembles of cortical neurons with cellular resolution and sub-millisecond precision. Since existing opsins were inadequate, we engineered new soma-targeted (ST) optogenetic tools, ST-ChroME and IRES-ST-eGtACR1, optimized for multiphoton activation and suppression. Employing a three-dimensional all-optical read-write interface, we demonstrate the ability to simultaneously photostimulate up to 50 neurons distributed in three dimensions in a 550 × 550 × 100-µm3 volume of brain tissue. This approach allows the synthesis and editing of complex neural activity patterns needed to gain insight into the principles of neural codes

The influence of paediatric HIV infection on circulating B cell subsets and CXCR5+ T helper cells

Antiretroviral therapy (ART) only partially restores HIV-induced alterations in lymphocyte populations. We assessed B and T cell phenotypes in a cohort of children from a single centre in the United Kingdom with perinatally acquired HIV compared to healthy controls. The majority of HIV infected children (44 of 56) were on fully suppressive combination ART. Children with perinatally acquired HIV had significantly lower memory B and CD4(+) CD45RO(+) CXCR5(+) [follicular T helper cell (Tfh)-like] T cell percentages. Detectable viraemia was associated with higher CD21(-) (activated and exhausted/tissue-like memory) B cells. A greater proportion of life spent on suppressive ART was associated with higher memory B cell percentages. These results suggest that early and sustained suppressive ART may preserve B and T cell phenotypes in perinatally acquired HIV and limit deficits in humoral immunity. A lower proportion of circulating Tfh-like cells in HIV infected children appears to be independent of HIV treatment history and ongoing HIV viraemia and warrants further investigation

Congenital Cytomegalovirus and Autoimmune Neutropenia: Cause or Coincidence?

BACKGROUND: Congenital cytomegalovirus (CCMV) accounts for high rates of infant morbidity and mortality. Neutropenia is a common finding in CCMV infection, of which the age of presentation overlaps with autoimmune neutropenia (AIN). AIN represents one of the most common forms of chronic neutropenia in childhood. METHODS: A literature search exploring biological associations between CCMV and AIN was conducted: PubMed (MEDLINE), Ovid and Web of Science. We further describe 2 cases of concurrent CCMV and AIN. Both cases were confirmed with the indirect granulocyte immunofluorescence test and alternative etiologies for neutropenia excluded. RESULTS: Our 2 patients represent confirmed cases of AIN in infants with CCMV. One patient demonstrated neutropenia while undergoing treatment with Valganciclovir, while the other was never treated. With interruption of Valganciclovir in infant A, neutrophil counts (ANC) did not improve and upon resumption of treatment ANC remained static. CONCLUSIONS: Further studies examining a possible biologic link between CCMV and AIN are advocated for. We encourage clinicians to actively consider AIN in the differential diagnosis of all infants with CCMV presenting with neutropenia

Tissue Doppler imaging following paediatric cardiac surgery : early patterns of change and relationship to outcome

In this study, tissue Doppler imaging (TDI) was used to assess changes in ventricular function following repair of congenital heart defects. The relationship between TDI indices, myocardial injury and clinical outcome was explored. Forty-five children were studied; 35 withcardiac lesions and 10 controls. TDI was performed preoperatively, on admission to paediatric intensive care unit (PICU) and day 1. Regional myocardial Doppler signals were acquired from the right ventricle (RV), left ventricle (LV) and septum. TDI indices included: peak systolicvelocities, isovolumetric velocities (IVV) and isovolumetric acceleration (IVA). Preoperatively, bi-ventricular TDI velocities in the study groupwere reduced compared with normal controls. Postoperatively, RV velocities were significantly reduced and this persisted to day-1 (PreOp vs. PICU and day-1: 7.7+2.2 vs. 3.4+1.0, P < 0.0001 and 3.55+1.29, P < 0.0001). LV velocities initially declined but recovered towards baseline by day-1 (PreOp vs. PICU: 5.31+1.50 vs. 3.51+1.23, P < 0.0001). Isovolumetric parameters in all regions were reduced throughout the postoperative period. Troponin-I release correlated with longer X-clamp times (r=0.82, P < 0.0001) and reduced RV velocities (r=0.42, P=0.028). Reduced pre- and postoperative LV velocities correlated with longer ventilation (PreOp: r=0.54, P=0.002; PostOp: r=0.42, P=0.026). This study identified reduced postoperative RV velocities correlated with myocardial injury while reduced LV TDI correlated with longer postoperative ventilation

Malignancy and all-cause mortality; incidence in adolescents and young adults living with perinatally acquired HIV.

Background: Adults living with HIV have an increased risk of malignancy yet there is a paucity of data for adolescents and young adults (AYA) with perinatally acquired HIV (PaHIV). Methods: Retrospective cohort analysis of all-cause mortality and malignancies in AYA with PaHIV aged 10-24 years attending a tertiary unit from 01 January 2004 to 31 December 2017, assessing cancer presentation, immunology and comparing mortality and malignancy incidence to age-matched UK general population rates. Results: A total of 290 AYA with PaHIV contributed 2644 person-years of follow up. Six (2.0%) died within the study period at a median age of 17 years (interquartile range [IQR]15-19), 3 of malignancy, 2 with end-stage HIV and 1 with cryptococcal meningitis. Overall mortality rate was 2.3/1000 person-years, with an age-matched general population rate of 0.2/1000 person-years. Eight (2.8%) were diagnosed with a malignancy; 6 with lymphoma (n=3 Hodgkin's, n=1 Burkitt's, n=2 B-cell) and one each with hepatocellular carcinoma and gastrointestinal adenocarcinoma. At cancer diagnosis the median age was 19 years (IQR 14-23), median CD4 T cell count was 453 cells/mm3 (IQR 231-645) and median length of HIV viremia was 15 years (IQR 12-17). The incidence rate of a malignancy was 3.0/1000 person-years in AYA with PaHIV, whilst that in the age-matched general population is 0.2/1000 person-years. Conclusion: AYA living with PaHIV had an increased risk of all-cause mortality and of malignancy compared to their uninfected peers, with the excess in malignancy driven by lymphomas. It is hoped that earlier access to antiretroviral therapy will mitigate some of the AIDS-defining and non-AIDS defining risks for future generations