intermediate distance
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Molecules ◽  
2021 ◽  
Vol 26 (24) ◽  
pp. 7690
Author(s):  
Robert Alan Aitken ◽  
Andrew D. Harper ◽  
Alexandra M. Z. Slawin

Three isomeric (benzyloxythienyl)oxazolines 9, 11 and 13 have been prepared and are found, upon treatment with a strong base, to undergo either Wittig rearrangement or intramolecular attack of the benzylic anion on the oxazoline function to give products derived from cleavage of the initially formed 3-aminothienofuran products. This pattern of reactivity is directly linked to the distance between the two reactive groups as determined by X-ray diffraction, with the greatest distance in 11 leading to exclusive Wittig rearrangement, the shortest distance in 13 giving exclusively cyclisation-derived products, and the intermediate distance in 9 leading to both processes being observed. The corresponding N-butyl amides were also obtained in two cases and one of these undergoes efficient Wittig rearrangement leading to a thieno[2,3-c]pyrrolone product.


2021 ◽  
Vol 11 (1) ◽  
Author(s):  
Marco Bassanello ◽  
Luciano Pasini ◽  
Marco Senzolo ◽  
Andrea Gambaro ◽  
Marco Roman ◽  
...  

AbstractThe emergence of severe acute respiratory syndrome type 2 coronavirus (SARS-CoV-2) and its complications have demonstrated the devastating impact of a new infectious pathogen. The organisational change promulgated by the isolation of affected communities is of extreme importance to achieve effective containment of the contagion and good patient care. The epidemiological study of the population of a small rural community in the North East of Italy revealed how much the virus had circulated during Spring, 2020, and how contagion has evolved after a prolonged lockdown. In the 1st phase, NAAT (Nucleic Acid Amplification Testing) was performed in cases with more or less severe symptoms and a study was performed to trace the infection of family members. Only 0.2% of the population tested positive on NAAT, via nasopharyngeal swab during this 1st phase. In the 2nd phase a random sample of the general population were tested for circulating anti-Sars-Cov-2 immunoglobulins. This showed that approximately 97.9% of the population were negative, while 2.1% (with positive IgG at a distance) of the population had contracted the virus in a mildly symptomatic or asymptomatic form. The main symptom in subjects who developed immunity was fever. Antibodies were found in subjects with forced coexistence with quarantined or infected subjects. The mutual spatial distance by categories has shown higher relative prevalence of IgG positive and IgM negative cases in close proximity but also far from the infected, with respect to an intermediate distance. This suggests that subjects living in thinly populated areas could come in contact with the virus more likely due to intentional/relational proximity, while those living nearby could also be infected through random proximity.


PLoS ONE ◽  
2021 ◽  
Vol 16 (9) ◽  
pp. e0253768
Author(s):  
Sergio Fagherazzi ◽  
Luca Baticci ◽  
Christine M. Brandon ◽  
Maria Cristina Rulli

The Labyrinth in the McMurdo Dry Valleys of Antarctica is characterized by large bedrock channels emerging from beneath the margin of Wright Upper Glacier. To study the morphodynamics of large subglacial channels cut into bedrock, we develop herein a numerical model based on the classical theory of subglacial channels and recent results on bedrock abrasion by saltating bed load. Model results show that bedrock abrasion in subglacial channels with pressurized flow reaches a maximum at an intermediate distance up-ice from the glacier snout for a wide range of sediment grain sizes and sediment loads. Close to the snout, the velocity is too low and the sediment particles cannot be mobilized. Far from the snout, the flow accelerates and sediment is transported in suspension, thus limiting particle impacts at the channel bottom and reducing abrasion. This non-monotonic relationship between subglacial flow and bedrock abrasion produces concave up bottom profiles in subglacial channels and potential cross-section constrictions after channel confluences. Both landforms are present in the bedrock channels of the Labyrinth. We therefore conclude that these geomorphic features are a possible signature of bedrock abrasion, rather than glacial scour, and reflect the complex interplay between transport rate, sediment load, and transport capacity in subglacial channels.


Author(s):  
Gagan Kalra ◽  
Parul Ichhpujani ◽  
Sahil Thakur ◽  
Urvashi Sharma

Purpose: Ophthalmology has seen numerous novel uses for smartphones over the years including fundus photography, telemedicine, and operative videography. However, anterior segment photography for assessing and documenting trabeculectomy bleb morphology using a smartphone has not been explored in detail. With the current study, we aim to characterize ideal illumination for the anterior segment smartphone photography in trabeculectomy patients. Methods: Thirty status post-trabeculectomy patients were enrolled in this study. Native camera application and FiLMiC pro camera application were used on iPhone X to compare bleb images using yellow and white pen-torches as illumination source. Measured bleb area was compared using ImageJ software from the two apps in different illumination settings by charting boxplots and using one-way ANOVA test using R software to establish consistency. Bland-Altman interoperability for repeatability of blebarea measurements was analyzed by plotting Bland-Altman plots. Signal-to-noise ratio was calculated using ImageJ for native camera images using slit-lamp camera images as reference. Subjective rating of these images was then performed by two experienced ophthalmologists and kappa coefficient was calculated for inter-operator repeatability. Statistical analysis was performed. Results: The measured bleb area from images taken from both apps showed no significant difference, thereby establishing consistency, and Bland-Altman analysis indicated good repeatability and reproducibility. It was noted that SNR was lower for images shot in close illumination as compared to the ones shot in intermediate and distant illumination. Cohen’s kappa coefficient was 0.7 for images with distant illumination using white light and 0.65 for images clicked with illumination at an intermediate distance using yellow light, suggesting substantial agreement between the observers. Conclusion: Smartphone photography is a reliable tool for morphological assessment trabeculectomy blebs. Optimal illumination helps achieve results free from digital noise and better delineation of specific morphological features. Intermediate illumination and distant illumination provides much better results in terms of high SNR while avoiding overexposure and clipping of highlight information in the images.


2021 ◽  
pp. 112067212110294
Author(s):  
Gerardo Valvecchia ◽  
Guadalupe Cervantes-Coste ◽  
Oscar Asis ◽  
Federico Pereyra ◽  
Manuel Garza-León ◽  
...  

Purpose: Evaluate the clinical outcomes of the secondary piggyback add-on IOL implantation in the ciliary sulcus for pseudophakic patients previously implanted with a monofocal IOL, who pursue a spectacle-free option after IOL surgery. Methods: A prospective case series including seven pseudophakic patients who underwent an in-the-bag monofocal IOL implantation. All eyes underwent a piggyback IOL implantation of the new sulcus designed A4 AddOn IOL in the ciliary sulcus as a secondary procedure for pseudophakic patients pursuing a spectacle-free option for near and intermediate distance after IOL surgery. Results: Seven eyes from six patients were included in this study, from which 4 (71.43%) were female, with a mean age of 58.33 ± 3.5 years (range 54–63; 95% CI 54.66, 62.01). The postoperative spherical equivalent at the 3-month visit was −0.10 m ± 0.82. Also, the UDVA was 0.11 ± 0.08 logMAR, the UIVA 0.01 ± 0.03, and the UNVA 0.01 ± 0.03 3 months after their surgical procedure. Conclusions: The A4 AddOn multifocal IOL’s secondary piggyback implant is an efficient alternative for monofocal pseudophakic patients seeking presbyopia solutions. This sulcus-designed IOL provides an optimal visual outcome for near and distance vision.


Author(s):  
Timothy Mast ◽  
Yu Pan ◽  
Carvel Holton ◽  
Mehdi Ahmadian

Abstract The primary intent of this study is to evaluate the effectiveness and utility of a laser-based measurement unit for qualitative assessment of the presence and amount of Top-of-Rail Friction Modifier (TOR or TORFM), at reasonably high speeds and over long distances in the field. As a capstone to this phase of development, a series of field tests were conducted on revenue service track in partnership with a local Class 1 railroad. For these tests, the Third Generation Rail Lubricity Sensor was mounted on a Remote-Controlled Rail Cart and tested continuously over several miles of track. This longer window is able to cover the domain of multiple wayside applicators over a distance of more than 3 miles, the expected carry distance of TORFM. The results of this testing demonstrate the capacity of optical sensors to measure and evaluate track lubricity. The signal characteristics at or near wayside applicators demonstrate a clear impulse from the heavy lubricant close to the applicator. Further, by collecting continuous data down track from a wayside applicator it is possible to observe several novel ways in which the TORFM and flange grease carries beyond the point of application. One such example is a clear spike in track lubricity when entering or exiting curves caused by the lateral shift of the wheelsets drawing fresh lubricant previously out of contact with the rail into contact creating a “phantom applicator” effect. These observations are crucial to understanding in detail the way the TORFM and flange grease is carried down track. They are also essential to creating predictive models for most effective application of friction modifiers to specific track geometries.


2021 ◽  
pp. 112067212199534
Author(s):  
Diogo Lopes ◽  
Tomás Loureiro ◽  
Rita Carreira ◽  
Sandra Rodrigues Barros ◽  
João Nobre Cardoso ◽  
...  

Purpose: To assess the clinical outcomes and patient satisfaction of the Tecnis Eyhance, an advanced monofocal intraocular lens (IOL), compared to a conventional monofocal IOL. Design: Retrospective case-control study. Methods: This study included 120 eyes of 60 patients (30 patients in each group) who underwent bilateral cataract surgery either with the implantation of conventional monofocal IOLs (Tecnis PCB00), as a control group, or advanced monofocal IOLs (Tecnis Eyhance ICB00). Ophthalmological evaluation included the measurement of binocular corrected distance visual acuity (CDVA), monocular and binocular uncorrected distance visual acuity (UDVA), and uncorrected intermediate VA (UIVA). In addition the binocular defocus curve was analyzed. Furthermore a subjective questionnaire (Catquest-9SF) was used to assess vision and life quality. Results: The average binocular UDVA was 20/22 in the ICB00 group and 20/20 in the PCB00 model ( p = 0.62). The average monocular UIVA was 20/32 in the ICB00 group and 20/40 in the control group ( p < 0.001). We found the binocular UIVA, had a mean value of 20/30 in the ICB00, compared to 20/40 in the control group ( p < 0.001). The reported dysphotopsia was not significantly different between both groups ( p = 0.56). Regarding the life quality questionnaire, the ICB00 group showed less difficulty in activities requiring intermediate vision. Conclusion: Our results demonstrated a significant improvement in visual acuity for intermediate distance in the ICB00 group compared to the control group, without compromising distance visual acuity. We also found a greater capability for intermediate distance activities (namely for computer use and reading price tags) when comparing ICB00 patients with the control group.


2020 ◽  
Vol 1 (4) ◽  
pp. 213-217
Author(s):  
Ji-Lin Tan ◽  
◽  
Shi-Man Yuan ◽  
Hao Du ◽  
Xia-Lu Liu ◽  
...  

AIM: To evaluate the clinical outcomes in terms of vision across distances (near, intermediate, and far), contrast sensitivity and subjective patient satisfaction after femtosecond laser-assisted cataract surgery (FLACS) with implantation of an extended range of vision (ERV) intraocular lens (IOL). METHODS: Forty patients (55 eyes) undergoing bilateral or monocular FLACS with implantation of the ERV IOL TECNIS Symfony (Johnson & Johnson Vision) were enrolled. Uncorrected distance (UDVA), intermediate (UIVA) and near visual acuities (UNVA) were evaluated at 3mo after surgery, as well the defocus curve, contrast sensitivity, patient satisfaction and spectacle independence. RESULTS: No severe complications occurred. All eyes showed a central position of the IOL in the capsular bag without tilting at 3mo after surgery. 3mo postoperative mean logMAR visual acuity at 5 m, 67 cm and 40 cm were -0.04 ±0.08, -0.17±0.22, 0.37±0.17, respectively. All patients obtained satisfactory UDVA and UIVA, as well as functional UNVA, meeting the needs of daily life. Spectacle independence rate was 94.55%. Contrast sensitivity results did not differ from those obtained with monofocal aspheric lenses. Likewise, no moderate and severe photic phenomena were reported. Mean patient satisfaction scores with distance, intermediate and near vision were 9.0, 9.0, and 7.0, respectively. CONCLUSION: FLACS with implantation of the ERV IOL TECNIS Symfony provides a successful visual restoration at far, intermediate distance and a functional-range near vision acuity, with minimal level of disturbing photic phenomena, and high rates of spectacle independence and patient satisfaction.


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