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Collaborative working arrangements between public agencies and vendors yield greater quality than adversarial relationships. What should the relationship be between government and its contractors? 'Business on a handshake' appears obsolete, [...]

Abstract The COVID-19 pandemic has posed enormous challenges for existing diagnostic tools to detect and monitor pathogens. Therefore, there is a need to develop point-of-care (POC) devices to perform fast, accurate, and accessible diagnostic methods to detect infections and monitor immune responses. Devices most amenable to miniaturization and suitable for POC applications are biosensors based on electrochemical detection. We have developed an impedimetric immunosensor based on an interdigitated microelectrode array (IMA) to detect and monitor SARS-CoV-2 antibodies in human serum. Conjugation chemistry was applied to functionalize and covalently immobilize the spike protein (S-protein) of SARS-CoV-2 on the surface of the IMA to serve as the recognition layer and specifically bind anti-spike antibodies. Antibodies bound to the S-proteins in the recognition layer result in an increase in capacitance and a consequent change in the impedance of the system. The impedimetric immunosensor is label-free and uses non-Faradaic impedance with low nonperturbing AC voltage for detection. The sensitivity of a capacitive immunosensor can be enhanced by simply tuning the ionic strength of the sample solution. The device exhibits an LOD of 0.4 BAU/ml, as determined from the standard curve using WHO IS for anti-SARS-CoV-2 immunoglobulins; this LOD is similar to the corresponding LODs reported for all validated and established commercial assays, which range from 0.41 to 4.81 BAU/ml. The proof-of-concept biosensor has been demonstrated to detect anti-spike antibodies in sera from patients infected with COVID-19 within 1 h. Photolithographically microfabricated interdigitated microelectrode array sensor chips & label-free impedimetric detection of COVID-19 antibody.

The article discusses the International Symposium for Testing and Failure Analysis (ISTFA 2012) that was held from November 11 to 15, 2012 in the U.S.

Information about several topics discussed at the 46th annual meeting by the International Reliability Physics Symposium (IRPS) on April 27 to May 1, 2008 in Phoenix, Arizona is presented. The symposium concentrates on the physics of failure and reliability, encompassing a host of microelectronics topics including electrostatic discharge/electrical overstress and latchup. It features the speech of Michael Pecht on the problem of products that fail in the field but pass qualification tests.

Information about the fourth Advance Materials and Failure Analysis (AMFA) workshop, which was held in Santa Clara, California on April 3, 2009 is presented. The workshop was aimed to provide a forum for the presentation and active discussion of technical issues and trends. The discussion was focused on materials characterization and failure analysis topics.

Information about the 47th annual International Reliability Physics Symposium (IRPS), which was held in Montreal, Quebec from April 26 to 30, 2009 is presented. The event includes two pre-symposium days of tutorials, an evening poster session, evening workshop sessions and vendor exhibits. The discussion was focused on topics that included high-k dielectrics, product reliability, interconnect reliability and reliability challenges for solar energy.

The article reports that Electronic Device Failure Analysis Society (EDFAS) members can retrieve EDFA magazine articles electronically. The members are encouraged to visit EDFAS' Web site, www.edfas.org, and log in to their MyEDFAS membership account. The members are advised to click on the EDFA Issues sub-button to get a listing of newsletters and EDFA magazines.

Background: Optical coherence tomography angiography (OCTA) has demonstrated good utility in qualitative analysis of retinal and choroidal vasculature and therefore may be relevant in the diagnostic and treatment efforts surrounding nonarteritic anterior ischemic optic neuropathy (NAION)., Methods: Retrospective, cross-sectional study of 10 eyes of 9 patients with a previous or new diagnosis of NAION that received imaging with OCTA between November 2015 and February 2016. Two independent readers qualitatively analyzed the retinal peripapillary capillaries (RPC) and peripapillary choriocapillaris (PCC) for flow impairment. Findings were compared with automated visual field and structural optical coherence tomography (OCT) studies., Results: Flow impairment seen on OCTA in the RPC corresponded to structural OCT deficits of the retinal nerve fiber layer (RNFL) and ganglion cell layer complex (GCC) in 80% and 100% of eyes, respectively, and to automated visual field deficits in 90% of eyes. Flow impairment seen on OCTA in the PCC corresponded to structural OCT deficits of the RNFL and GCC in 70% and 80% of eyes, respectively, and to visual field deficits in 60%-80% of eyes., Conclusions: OCTA can noninvasively visualize microvascular flow impairment in patients with NAION.

Background: Central vision loss in diabetic retinopathy is commonly related to diabetic macular edema (DME). The objective of this study was to describe changes between consecutive visits on optical coherence tomography angiography (OCTA) of the foveal avascular zone (FAZ) in eyes with DME., Methods: 20 eyes from 14 patients with DME were imaged on 2 successive clinic visits separated by at least 1 month. The mean interval between visits was 3.2 months. The only intervention used was intravitreal anti-VEGF in 11 eyes; the others were observed over time without treatment. Two different readers measured FAZ area using a pseudo-automated tool in comparison to a manual tracing tool. Qualitative changes in the appearance of the vasculature surrounding the FAZ were also recorded. The retinal capillary plexus was segmented into deep and superficial plexuses, and FAZ measurements were done on the superficial, deep, and summated plexuses., Results: Pseudo-automated and manual measurements of FAZ area decreased significantly ( p  < 0.05) between visits in the deep, superficial, and summated plexuses. Qualitative analysis of vasculature surrounding the FAZ showed that most of the vascular changes (65%) over time were visible in the deep plexus, compared to 30 and 20% in the superficial and summated plexuses, respectively., Conclusions: The most significant differences in FAZ size over time were in the summated plexus ( p  < 0.001), while changes in FAZ appearance were most prominent in the deep plexus. Absolute decrease in FAZ size over visits was largest in the deep plexus. Our results demonstrate that OCTA can effectively be used to measure FAZ area in patients with DME, visualize qualitative changes in retinal vasculature, and visualize the segmentation levels at which these changes can be best appreciated. However, larger studies are needed to evaluate the reproducibility of manual and pseudo-automated measuring techniques.

Background: To investigate the choroidal thickness in older patients with central serous chorioretinopathy (CSCR) compared to age-matched normal subjects., Methods: Fifteen patients (30 eyes) with CSCR, all aged ≥60 years, and 21 age-matched normal subjects (21 eyes) underwent high-definition raster scanning using SD-OCT. Both eyes from CSCR patients were included in the analysis. The eyes in patients with CSCR were divided into two groups: active CSCR (17 eyes) if there was foveal-involving subretinal fluid and inactive contralateral eye group (13 eyes). Choroidal thickness was measured from the posterior edge of the retinal pigment epithelium to the choroidal-scleral junction at 500 µm intervals up to 2500 µm temporal and nasal to the fovea (11 locations)., Results: The mean age of the patients with CSCR was 68.87 ± 6.83 years (mean ± standard deviation). Reliable measurements of choroidal thickness were obtainable in 70.6 % of eyes examined. The choroid was statistically significantly thicker in eyes with both active CSCR ( P  < 0.001) and inactive contralateral eyes ( P  < 0.01) when compared to normal age-matched eyes. The subfoveal choroid was 95 µm ( P  < 0.01) thicker in eyes with active CSCR (338.05 ± 31.42 µm) compared with normal eyes (243.05 ± 13.39 µm). The subfoveal choroid thickness in the inactive contralateral eyes was numerically greater than normal, and it was not statistically significantly thicker compared to the normal eyes (difference-55.68 µm, P  > 0.05)., Conclusion: Choroid in older patients with active CSCR was thicker than the choroid in age-matched normal eyes. It is important to consider CSCR as a differential diagnosis of serous retinal detachment in elderly patients with thickened choroid and to consider SD-OCT as an imaging modality by which to evaluate the choroidal thickness.

Purpose: To utilize optical coherence tomography (OCT) and OCT angiography (OCTA) to describe alterations in the retinal and choriocapillaris vasculature following remote laser photocoagulation. Lesions are classified on the basis of choriocapillaris alteration as evaluated on en face OCTA., Methods: This was a retrospective, cross-sectional study analyzing 28 laser photocoagulation scars from 8 patients treated for diabetic macular edema. All eyes were analyzed using a combination of OCTA, en face and cross-sectional OCT, and fundus photography. Two masked readers scored images for alterations at the level of the retinal pigment epithelium (RPE), choroid, and choriocapillaris. Laser photocoagulation lesions were classified as deep if choriocapillaris alteration was present on OCTA; lesions were classified as superficial if no choriocapillaris alteration was present on OCTA., Results: Optical coherence tomography angiography was found to be useful for evaluation of choriocapillaris alteration underlying regions of laser scarring. Of the 28 analyzed laser scars, 13 were classified as superficial and 15 were classified as deep., Conclusions: Optical coherence tomography angiography can be used to visualize choriocapillaris alterations associated with focal laser photocoagulation treatment.

Purpose: To investigate the appearance of choriocapillaris (CC) flow under drusen by comparing long-wavelength (1050 nm) swept-source optical coherence tomography (SS-OCT) angiography with shorter-wavelength (840 nm) spectral-domain (SD) OCT angiography., Methods: Patients with drusen imaged on both devices on the same day were selected and graded. Ambiguous OCT angiography (OCTA) signal loss was defined as low OCTA signal on the en face OCTA CC image that also had low OCT signal in the corresponding area on the en face OCT CC image and OCT B-scans. Unambiguous OCTA signal loss was defined as low OCTA signal on the en face OCTA CC image that did not have low OCT signal in the corresponding area on the en face OCT CC image and OCT B-scans. False-positive flow impairment on SS-OCTA was defined as ambiguous OCTA signal loss on SS-OCTA but no OCTA signal loss on SD-OCTA. False-positive flow impairment on SD-OCTA was defined as ambiguous OCTA signal loss on SD-OCTA but no OCTA signal loss on SS-OCTA., Results: Nine eyes from seven patients were enrolled, 23 drusen were analyzed. On 840-nm SD-OCTA, 17 drusen (73.9%) exhibited OCTA signal loss. Fourteen (82.4%) were classified as ambiguous, and three (17.6%) were classified as unambiguous; 10 (58.8%) were classified as having false-positive flow impairment. On 1050-nm SS-OCTA, seven drusen (30.4%) exhibited OCTA signal loss and were classified as unambiguous; none were classified as having false-positive flow impairment., Conclusions: Results showed that 1050-nm SS-OCTA appears less prone to producing areas of false-positive flow impairment under drusen.