COVID-19, lockdowns and international trade: evidence from firm-level data.

The COVID-19 pandemics and the lockdowns imposed to mitigate the rise of infections beyond manageable levels strongly affected international trade. Although the health crisis and the mobility restrictions associated with lockdowns are closely related, their impacts on international trade have a different nature. This paper uses monthly firm-level trade data for Portuguese firms to measure the impact of partner countries' lockdowns on nominal export and import flows during 2020 and the first half of 2021, while also assessing the impact of the health crisis. The high time frequency and granularity of the data contribute to the identification of the impact of these obstacles on trade. We conclude that the detrimental impact of lockdowns is sizeable and broadly similar in exports and imports, and the impact of the health conditions is slightly stronger in exports. There is evidence that the detrimental impact of lockdowns was stronger for larger firms, for those with higher geographical concentration of trade, more integrated in global value chains and in the upper quartiles of the trade unit value distribution. The negative impact is also estimated to be larger for industries with high import content and for trade partners that are more important as sources of value added to be embodied in Portuguese exports. Results also suggest that exports adapted to the prevailing circumstances as of June 2020, but such an effect is not clear in imports.

Towards a Uniform Metrological Assessment of Grating-Based Optical Fiber Sensors: From Refractometers to Biosensors.

A metrological assessment of grating-based optical fiber sensors is proposed with the aim of providing an objective evaluation of the performance of this sensor category. Attention was focused on the most common parameters, used to describe the performance of both optical refractometers and biosensors, which encompassed sensitivity, with a distinction between volume or bulk sensitivity and surface sensitivity, resolution, response time, limit of detection, specificity (or selectivity), reusability (or regenerability) and some other parameters of generic interest, such as measurement uncertainty, accuracy, precision, stability, drift, repeatability and reproducibility. Clearly, the concepts discussed here can also be applied to any resonance-based sensor, thus providing the basis for an easier and direct performance comparison of a great number of sensors published in the literature up to now. In addition, common mistakes present in the literature made for the evaluation of sensor performance are highlighted, and lastly a uniform performance assessment is discussed and provided. Finally, some design strategies will be proposed to develop a grating-based optical fiber sensing scheme with improved performance.

Advanced Glycation End Products Evolution after Pancreas-Kidney Transplantation: Plasmatic and Cutaneous Assessments.

Diabetes mellitus leads to increased Advanced Glycation End Products (AGE) production, which has been associated with secondary diabetic complications. Type 1 diabetic patients undergoing pancreas-kidney transplantation (SPKT) can restore normoglycemia and renal function, eventually decreasing AGE accumulation. We aimed to prospectively study AGE evolution after SPKT. Circulating AGE were assessed in 20 patients, at time 0 (T0), 3 months (T3), 6 months (T6), and 12 months (T12) after successful SPKT. Global AGE and carboxymethyllysine (CML) were analyzed, as well as advanced oxidation protein products (AOPP). Skin biopsies were obtained at T0 and T12. Immunohistochemistry with anti-AGE antibody evaluated skin AGE deposition. AGE mean values were 16.8 ± 6.4 µg/mL at T0; 17.1 ± 3.8 µg/mL at T3; 17.5 ± 5.6 µg/mL at T6; and 16.0 ± 5.2 µg/mL at T12. CML mean values were 0.94 ± 0.36 ng/mL at T0; 1.11 ± 0.48 ng/mL at T3; 0.99 ± 0.42 ng/mL at T6; and 0.78 ± 0.38 ng/mL at T12. AOPP mean values were 130.1 ± 76.8 µMol/L at T0; 137.3 ± 110.6 µMol/L at T3; 116.4 ± 51.2 µMol/L at T6; and 106.4 ± 57.9 µMol/L at T12. CML variation was significant (P = 0.022); AOPP variation was nearly significant (P = 0.076). Skin biopsies evolved mostly from a cytoplasmic diffuse to a peripheral interkeratinocytic immunoreaction pattern; in 7 cases, a reduction in AGE immunoreaction intensity was evident at T12. In conclusion, glycoxidation markers decrease, plasmatic and on tissues, may start early after SPKT. Studies with prolonged follow-up may confirm these data.

Biosensor for label-free DNA quantification based on functionalized LPGs.

A label-free fiber optic biosensor based on a long period grating (LPG) and a basic optical interrogation scheme using off the shelf components is used for the detection of in-situ DNA hybridization. A new methodology is proposed for the determination of the spectral position of the LPG mode resonance. The experimental limit of detection obtained for the DNA was 62±2nM and the limit of quantification was 209±7nM. The sample specificity was experimentally demonstrated using DNA targets with different base mismatches relatively to the probe and was found that the system has a single base mismatch selectivity.

Monocarboxylate transporter 2 (MCT2) as putative biomarker in prostate cancer.

BACKGROUND: Monocarboxylate transporter 2 (MCT2) is a transmembrane protein involved in the transport of monocarboxylates such as pyruvate and lactate. In a previous study we described overexpression of MCT2 in prostate carcinoma raising the hypothesis of using MCT2 as a possible biomarker in prostate cancer. With the present study we aimed to compare the pattern of expression of MCT2 and alpha-methylacyl-CoA racemase (AMACR), in prostate carcinoma, PIN lesions, non-neoplastic prostate tissue, and normal prostate and compare their sensitivity and specificity. Also, we wanted to evaluate the value of using MCT2 in combination with AMACR and the negative markers 34ßE12 or p63 to detect prostate cancer. METHODS: A total of 349 cases, including prostate carcinoma, non-neoplastic prostate tissue and PIN lesions, from radical prostatectomies were examined by immunohistochemistry for AMACR, MCT2, p63, and 34ßE12, using tissue microarrays (TMAs). Normal prostate from radical cystoprostatectomy was also studied. RESULTS: Our study revealed that MCT2, similarly to AMACR, was consistently expressed in prostate cancer regardless of the Gleason score. In combination with AMACR and p63 or 34ßE12, MCT2 helped to improve the diagnosis of prostate carcinoma. Also, overexpression of MCT2 as well as AMACR in PIN lesions may indicate the involvement of these two proteins in prostate cancer initiation. CONCLUSIONS: We provided evidence for the presence of MCT2 in prostate cancer, selectively labeling malignant glands. Importantly, assessment of MCT2 together with AMACR, along with the negative markers, highly increases the accuracy in prostate cancer diagnosis.

Fiber optic-based refractive index sensing at INESC Porto.

A review of refractive index measurement based on different types of optical fiber sensor configurations and techniques is presented. It addresses the main developments in the area, with particular focus on results obtained at INESC Porto, Portugal. The optical fiber sensing structures studied include those based on Bragg and long period gratings, on micro-interferometers, on plasmonic effects in fibers and on multimode interference in a large spectrum of standard and microstructured optical fibers.