bluuebunny/crossref_metadata_2025_split huggingface dataset:
Merkel Cell Carcinoma: Changing Practice Patterns and Impact on Recurrence-Free and Overall Survival at a Single Institution and Nationally
Authors: Esposito Andrew , Jacobs Daniel , Ariyan Stephan , Galan Anjela , Kluger Harriet , Clune James , Weiss Sarah , Tran Thuy , Olino Kelly 
Published: September 2021

Abstract
Background
Merkel cell carcinoma (MCC) is an aggressive neuroendocrine carcinoma of the skin. Our report describes the evolution of management and characteristics associated with recurrence, disease-specific survival (DSS) and overall survival (OS) in the treatment of MCC.

Methods
A single institution retrospective review of MCC and SEER data to determine factors associated with RFS, DSS, and OS using a multivariable Cox regression on inverse-probability weighted cohorts.

Results
One hundred fifty-nine patients were identified with a median age of 75. Of these, 96% were Caucasian and 60% male. Fifty-eight out of 159 (36%) of all patients were deceased with 21/58 (36%) dead from MCC with a median follow-up of 3.1 years. Institutionally, trends over time demonstrated an increased use of immunotherapy with a concomitant decrease in chemotherapy and decreased use of radiotherapy alone. Institutionally and nationally, there has been increased surgical nodal staging. Institutionally, factors associated with shorter DSS included advanced age, active cigarette smoker (p = 0.002), cT2 disease (p = 0.007), and MCC with unknown primary (p < 0.001). Institutionally, factors associated with shorter OS included ages ≥ 75 years (p < 0.001), an immunocompromised state (p < 0.001), truncal primary site (p = 0.002), and cT2 disease (HR 9.59, p < 0.001).

Conclusion
Changing practice patterns in MCC management have been driven by the adoption of immunotherapy. Our study highlights that competing risks of mortality in MCC patients likely prevents OS from being an accurate surrogate outcome measure to understand factors associated with DSS.
Emergency CT misdiagnosis in acute aortic syndrome
Authors: Dreisbach John G , Rodrigues Jonathan CL , Roditi Giles 
Published: September 2021

Objectives:
This cross-sectional study assessed the accuracy of emergency CT reports at presentation in acute aortic syndrome (AAS).

Methods:
Retrospective identification of cases of AAS presenting within a large health board with three acute hospitals receiving adult patients between January 2013 and December 2016. CT studies and reports at presentation were reviewed for discrepancies related to diagnosis, complications and classification by two cardiovascular radiologists. The specialist interest of the original reporters, clinically suspected diagnosis at referral for CT and technical adequacy of the scans were also assessed. False-positive diagnoses were identified and evaluated separately.

Results:
Among 88 consecutive confirmed cases of AAS at least one discrepancy was identified in 31% (n = 27), including failure to identify or misinterpretation of the AAS itself in 15% (n = 13), haemorrhage in 13% (n = 11), branch involvement in 9% (n = 8), and misclassification in 3% (n = 3). All discrepancies occurred among the 80% (n = 70) of cases reported by radiologists without specialist cardiovascular interest. 26% (n = 23/88) of AAS cases were not clinically suspected at referral for CT and although this was associated with suboptimal protocols, only 51% of CT scans among suspected cases were technically adequate. Seven false-positive diagnoses were identified, three of which related to motion artefact.

Conclusion:
Significant discrepancies are common in the emergency CT assessment of positive cases AAS and this study highlights important pitfalls in CT technique and interpretation. The absence of discrepancies among radiologists with specialist cardiovascular interest suggests both suspected and confirmed cases warrant urgent specialist review.

Advances in knowledge:
CT angiography is central to the diagnosis of AAS; however, significant radiology discrepancies are common among non-specialists. This study highlights important pitfalls in both CT technique as well as interpretation and supports routine specialist cardiovascular imaging input in the emergency assessment of AAS.
Functional magnetic resonance imaging for distinguishing type of papillary renal cell carcinoma: a preliminary study
Authors: Zhu Qingqiang , Ye Jing , Zhu Wenrong , Wu Jingtao , Chen Wenxin , Ling Jun 
Published: September 2021

Objective:
To investigate the feasibility of magnetic resonance diffusion kurtosis imaging (DKI) and intravoxel incoherent motion (IVIM) for distinguishing Type 1 and 2 of papillary renal cell carcinoma (PRCC).

Methods:
A total of Type 1 (n = 20) and Type 2 (n = 16) of PRCC were examined by pathology. For DKI and IVIM, mean diffusivity (MD), fractional anisotropy (FA), mean kurtosis (MK), kurtosis anisotropy (KA), radial kurtosis (RK), diffusivity (D), pseudodiffusivity (D*) and perfusion fraction (f) were performed in assessment of type of PRCC.

Results:
The mean SNRs of IVIM and DKI images at b = 1500 and 2000 s/mm2 were 8.6 ± 0.8 and 7.8 ± 0.6. Statistically significant differences were observed in MD and D values (1.11 ± 0.23 vs 0.73 ± 0.13, 0.91 ± 0.24 vs 0.49 ± 0.13, p &lt; 0.05) between Type 1 and Type 2 of PRCC, while comparable FA, RK, D* and f values were found between Type 1 and Type 2 of PRCC (p &gt; 0.05). Statistically significant differences were observed in MK and KA values (1.23 ± 0.16 vs 1.91 ± 0.26, 1.49 ± 0.19 vs 2.36 ± 0.39, p &lt; 0.05) between Type 1 and Type 2 of PRCC. Areas of MD, MK, KA and D values under ROC curves for differentiating Type 1 and Type 2 of PRCC were 0.836, 0.818, 0.881 and 0.766, respectively. Using MD, MK, KA and D values of 0.93, 1.64, 1.94, 0.68 as the threshold value for differentiating Type 1 from Type 2 of PRCC, the best result obtained had a sensitivity of 85.0%, 80.0%, 90.0%, 85.0%, a specificity 75.0%, 68.7%, 87.5%, 81.2%, and an accuracy of 83.3%, 80.5%, 88.9%, 86.1%, respectively.

Conclusion:
DKI and IVIM are feasible techniques for distinguishing type of PRCC, given an adequate SNR of IVIM and DKI images.

Advances in knowledge:
1. MD and D values are higher for Type 1 of PRCC and lower for Type 2 of PRCC.
2. MK and KA values are higher for Type 2 of PRCC and lower for Type 1 of PRCC.
3. DKI and IVIM can be used as clinical biomarker for PRCC type’s differential diagnosis, given an adequate SNR.
Axillary ultrasonography combined with pre-operative wire localisation of clipped node in nodal restaging after neoadjuvant chemotherapy in node positive breast cancer patients: a pilot study
Authors: Pulappadi Vishnu Prasad , Paul Shashi , Hari Smriti , Dhamija Ekta , Manchanda Smita , Kataria Kamal , Mathur Sandeep , Mani Kalaivani , Gogia Ajay , Deo SVS 
Published: September 2021

Objective: To evaluate the role of axillary ultrasonography (axUS) and ultrasound-guided pre-operative wire localisation of pre-treatment positive clipped node (CN) for prediction of nodal response to neoadjuvant chemotherapy (NACT) in node positive breast carcinoma patients. Methods and materials: A prospective study was conducted between June 2018 and August 2020 after Ethics Committee approval. Breast carcinoma patients (cT1-cT4b) with palpable axillary nodes (cN1-cN3) and suitable for NACT were recruited after written informed consent. Single, most suspicious node was biopsied and clipped. Nodal response to NACT was assessed on axUS. Wire localisation of CN was performed prior to axillary lymph node dissection (ALND). Diagnostic performances of axUS and CN excision were assessed. Results: Of the 69 patients evaluated, 32 patients (mean age, 43.5 ± 11.8 years; females, 31/32 [97%]; pre-menopausal, 18/32 [56.3%]) with metastatic nodes who received NACT were included. Nodal pathological complete response rate was 34.4% (11/32) overall and 70% (7/10) in patients with ≤2 suspicious nodes on pre-NACT axUS. False-negative rates (FNRs) of axUS and CN excision were 4.8% and 28.6% respectively. Combination of post-NACT axUS and CN excision had an FNR of 4.8% overall and 0% in patients with ≤2 suspicious nodes on pre-NACT axUS. Conclusion: Combination of AxUS and ultrasound-guided wire localisation of pre-treatment positive CN has high diagnostic accuracy for nodal restaging after NACT in node positive breast cancer patients. Advances in knowledge: Addition of axUS assessment to wire localisation of CN reduces its FNR for detecting residual metastasis after NACT.
The role of Vitamin D in orthopaedic infection: a systematic literature review
Authors: Zargaran Alexander , Zargaran David , Trompeter Alex J. 
Published: September 2021

Aims Orthopaedic infection is a potentially serious complication of elective and emergency trauma and orthopaedic procedures, with a high associated burden of morbidity and cost. Optimization of vitamin D levels has been postulated to be beneficial in the prevention of orthopaedic infection. This study explores the role of vitamin D in orthopaedic infection through a systematic review of available evidence. Methods A comprehensive search was conducted on databases including Medline and Embase, as well as grey literature such as Google Scholar and The World Health Organization Database. Pooled analysis with weighted means was undertaken. Results Pooled analysis of four studies including 651 patients found the mean 25(OH)D level to be 50.7 nmol/l with a mean incidence of infection of 70%. There was a paucity of literature exploring prophylactic 25(OH)D supplementation on reducing orthopaedic infection, however, there was evidence of association between low 25(OH)D levels and increased incidence of orthopaedic infection. Conclusion The results indicate a significant proportion of orthopaedic patients have low 25(OH]D levels, as well as an association between low 25(OH)D levels and orthopaedic infection, but more randomized controlled trials need to be conducted to establish the benefit of prophylactic supplementation and the optimum regimen by dose and time. Cite this article: Bone Jt Open 2021;2(9):721–727.
Telemedicine in orthopaedic surgery during the COVID-19 pandemic
Authors: Yakkanti Ramakanth R. , Sedani Anil B. , Baker Lauren C. , Owens Patrick W. , Dodds Seth D. , Aiyer Amiethab A. 
Published: September 2021

Aims This study assesses patient barriers to successful telemedicine care in orthopaedic practices in a large academic practice in the COVID-19 era. Methods In all, 381 patients scheduled for telemedicine visits with three orthopaedic surgeons in a large academic practice from 1 April 2020 to 12 June 2020 were asked to participate in a telephone survey using a standardized Institutional Review Board-approved script. An unsuccessful telemedicine visit was defined as patient-reported difficulty of use or reported dissatisfaction with teleconferencing. Patient barriers were defined as explicitly reported barriers of unsatisfactory visit using a process-based satisfaction metric. Statistical analyses were conducted using analysis of variances (ANOVAs), ranked ANOVAs, post-hoc pairwise testing, and chi-squared independent analysis with 95% confidence interval. Results The survey response rate was 39.9% (n = 152). The mean age of patients was 51.1 years (17 to 85), and 55 patients (38%) were male. Of 146 respondents with completion of survey, 27 (18.5%) reported a barrier to completing their telemedicine visit. The majority of patients were satisfied with using telemedicine for their orthopaedic appointment (88.8%), and found the experience to be easy (86.6%). Patient-reported barriers included lack of proper equipment/internet connection (n = 13; 8.6%), scheduling difficulty (n = 2; 1.3%), difficulty following directions (n = 10; 6.6%), and patient-reported discomfort (n = 2; 1.3%). Barriers based on patient characteristics were age > 61 years, non-English primary language, inexperience with video conferencing, and unwillingness to try telemedicine prior to COVID-19. Conclusion The barriers identified in this study could be used to screen patients who would potentially have an unsuccessful telemedicine visit, allowing practices to provide assistance to patients to reduce the risk of an unsuccessful visit. Cite this article: Bone Jt Open 2021;2(9):745–751.
Perspective: Agricultural Aerial Application with Unmanned Aircraft Systems: Current Regulatory Framework and Analysis of Operators in the United States
Authors: Rodriguez Roberto 
Published: September 2021

HighlightsThe FAA has used two exemptions (17261 and 18009) as precedents for approval of numerous agricultural operations for unmanned aircraft systems (UAS).While many operators have received exemptions, a significant portion have not received an agricultural aircraft operator certificate (AAOC), despite the need for both to operate UAS in agricultural operations.Operators who have both an exemption and an AAOC tend to be clustered in geographic areas, with many states without a single such operator.Abstract. Unmanned aircraft systems (UAS) have seen rapid growth in many industries in the U.S. since the introduction of small UAS regulations (14 CFR § 107). However, adoption of UAS for agricultural aerial application has been limited. Two landmark regulatory exemptions by the Federal Aviation Administration (FAA) have laid the foundation for commercial agricultural aerial application with UAS. Since the initial introduction of these exemptions, the pace of new exemptions for agricultural aerial application with UAS has remained steady. By the end of 2019, 64 operators had received exemptions in which the FAA cited one of the two landmark exemptions as a precedent. This study analyzed these exemptions to determine geographic distribution, aircraft manufacturer, number of employees, and time to operator certification. Results indicate that less than half of operators who received an exemption from the FAA became certified for aerial application. Additionally, certified operators were not evenly distributed throughout the U.S. despite the broader distribution of exemption holders. Two UAS manufacturers dominated the market, with over 80% of exemptions requesting UAS from one or both manufacturers. While regulatory hurdles for agricultural aerial application with UAS have been substantially reduced through the introduction of standardized exemptions, this has not resulted in the anticipated influx of certified operators. There are additional impediments preventing operator certification, including technological limitations of currently available UAS, which need to be addressed to improve the rate of UAS integration into agricultural aerial application. Keywords: Chemical applications, Drone, Precision agriculture, UAS, UAV, Unmanned aerial vehicle, Unmanned aircraft systems.
Beobachtungen zur diachronischen Entwicklung der Verbal-periphrase GEHEN + PARTIZIP PERFEKT im italienisch-spanischen Sprachvergleich
Authors: Mayr Paul 
Published: September 2021

The verbal periphrases constitute a typological feature of the Romance languages and they are especially frequent in the Iberoromanic languages. In the context of this paper the diachronic evolution of the Italian periphrase andare + participio passato, which has a diathetic, modal and resultative function, and its formal, but not functional equivalent in Spanish, ir + participio pasado, will be analysed. The study will focus on the analysis of semantic and functional values of these verbal constructions in different historical phases of the Italian and (European) Spanish language in order to investigate the convergences and divergences which arise between the two languages. In addition, some equivalent constructions in other Romance languages, e. g. Catalan and Portuguese, will occasionally be taken in consideration.
Unsupervised feature learning and clustering of particles imaged in raw holograms using an autoencoder
Authors: Liu Zonghua , Thevar Thangavel , Takahashi Tomoko , Burns Nicholas , Yamada Takaki , Sangekar Mehul , Lindsay Dhugal , Watson John , Thornton Blair 
Published: September 2021

Digital holography is a useful tool to image microscopic particles. Reconstructed holograms give high-resolution shape information that can be used to identify the types of particles. However, the process of reconstructing holograms is computationally intensive and cannot easily keep up with the rate of data acquisition on low-power sensor platforms. In this work, we explore the possibility of performing object clustering on holograms that have not been reconstructed, i.e., images of raw interference patterns, using the latent representations of a deep-learning autoencoder and a self-organizing mapping network in a fully unsupervised manner. We demonstrate this concept on synthetically generated holograms of different shapes, where clustering of raw holograms achieves an accuracy of 94.4%. This is comparable to the 97.4% accuracy achieved using the reconstructed holograms of the same targets. Directly clustering raw holograms takes less than 0.1 s per image using a low-power CPU board. This represents a three-order of magnitude reduction in processing time compared to clustering of reconstructed holograms and makes it possible to interpret targets in real time on low-power sensor platforms. Experiments on real holograms demonstrate significant gains in clustering accuracy through the use of synthetic holograms to train models. Clustering accuracy increased from 47.1% when the models were trained only on the real raw holograms, to 64.1% when the models were entirely trained on the synthetic raw holograms, and further increased to 75.9% when models were trained on the both synthetic and real datasets using transfer learning. These results are broadly comparable to those achieved when reconstructed holograms are used, where the highest accuracy of 70% achieved when clustering raw holograms outperforms the highest accuracy achieved when clustering reconstructed holograms by a significant margin for our datasets.
Pose-varied swing arm profilometer test for off-axis aspheric surfaces with strong asphericity
Authors: Xiong Ling , Luo Xiao , Zhang Xuejun , Qi Erhui , Hu Haixiang , Liu Zhenyu , Zhang Feng 
Published: September 2021

The swing arm profilometer (SAP) has been widely used to test large aspheric optics by measuring the asphericity from its best-fitting sphere (BFS). To further improve the test accuracy, we propose a pose-varied test mode for the SAP with a shorter-range probe to measure off-axis aspheric surfaces with stronger asphericity. In contrast to the classical SAP mode in which the air-table is fixed in a stationary position during measurement, we adjust the pose of each scan arc to match the local BFS and the measurement range of the probe decreases to half that of the global asphericity. To verify the effectiveness, we conduct experiments on an off-axis asphere with a diameter of 3 and 2 m. Compared with a classical SAP mode, it achieved an improved performance of 50% higher repeatability and 32% higher accuracy.
On-chip optical levitation with a metalens in vacuum
Authors: Shen Kunhong , Duan Yao , Ju Peng , Xu Zhujing , Chen Xi , Zhang Lidan , Ahn Jonghoon , Ni Xingjie , Li Tongcang 
Published: September 2021

Optical levitation of dielectric particles in vacuum is a powerful technique for precision measurements, testing fundamental physics, and quantum information science. Conventional optical tweezers require bulky optical components for trapping and detection. Here, we design and fabricate an ultrathin dielectric metalens with a high numerical aperture of 0.88 at 1064 nm in vacuum. It consists of 500-nm-thick silicon nano-antennas, which are compatible with an ultrahigh vacuum. We demonstrate optical levitation of nanoparticles in vacuum with a single metalens. The trapping frequency can be tuned by changing the laser power and polarization. We also transfer a levitated nanoparticle between two separated optical tweezers. Optical levitation with an ultrathin metalens in vacuum provides opportunities for a wide range of applications including on-chip sensing. Such metalenses will also be useful for trapping ultracold atoms and molecules.
SARS-CoV-2 infections among Australian passengers on the Diamond Princess cruise ship: A retrospective cohort study
Authors: Walker Liz J. , Codreanu Tudor A. , Armstrong Paul K. , Goodwin Sam , Trewin Abigail , Spencer Emma , Colquhoun Samantha M. , Stephens Dianne M. , Baird Rob W. , Douglas Nicholas M. , Cribb Danielle , Owen Rhonda , Kelly Paul , Kirk Martyn D. 
Published: September 2021

Background
Prolonged periods of confined living on a cruise ship increase the risk for respiratory disease transmission. We describe the epidemiology and clinical characteristics of a SARS-CoV-2 outbreak in Australian passengers on the Diamond Princess cruise ship and provide recommendations to mitigate future cruise ship outbreaks.

Methods
We conducted a retrospective cohort study of Australian passengers who travelled on the Diamond Princess from 20 January until 4 February 2020 and were either hospitalised, remained in Japan or repatriated. The main outcome measures included an epidemic curve, demographics, symptoms, clinical and radiological signs, risk factors and length of time to clear infection.

Results
Among 223 Australian passengers, 56 were confirmed SARS-CoV-2 positive. Forty-nine cases had data available and of these over 70% had symptoms consistent with COVID-19. Of symptomatic cases, 17% showed signs and symptoms before the ship implemented quarantine and a further two-thirds had symptoms within one incubation period of quarantine commencing. Prior to ship-based quarantine, exposure to a close contact or cabin mate later confirmed SARS-CoV-2 positive was associated with a 3.78 fold (95% CI, 2.24–6.37) higher risk of COVID-19 acquisition compared to non-exposed passengers. Exposure to a positive cabin mate during the ship’s quarantine carried a relative risk of 6.18 (95% CI, 1.96–19.46) of developing COVID-19. Persistently asymptomatic cases represented 29% of total cases. The median time to the first of two consecutive negative PCR-based SARS-CoV-2 assays was 13 days for asymptomatic cases and 19 days for symptomatic cases (p = 0.002).

Conclusion
Ship based quarantine was effective at reducing transmission of SARS-CoV-2 amongst Australian passengers, but the risk of infection was higher if an individual shared a cabin or was a close contact of a confirmed case. Managing COVID-19 in cruise ship passengers is challenging and requires enhanced health measures and access to onshore quarantine and isolation facilities.