Assessment of dual frequency GNSS observations from a Xiaomi Mi 8 android smartphone and positioning performance analysis

On May 2018 the world’s first dual-frequency Global Navigation Satellite System (GNSS) smartphone produced by Xiaomi equipped with a Broadcom BCM47755 chip was launched. It is able to receive L1/E1/ and L5/E5 signals from GPS, Galileo, Beidou, and GLONASS (GLObal NAvigation Satellite System) satellites. The main aim of this work is to achieve the phone’s position by using multi-constellation, dual frequency pseudorange and carrier phase raw data collected from the smartphone. Furthermore, the availability of dual frequency raw data allows to assess the multipath performance of the device. The smartphone’s performance is compared with that of a geodetic receiver. The experiments were conducted in two different scenarios to test the smartphone under different multipath conditions. Smartphone measurements showed a lower C/N0 and higher multipath compared with those of the geodetic receiver. This produced negative effects on single-point positioning as showed by high root mean square error (RMS). The best positioning accuracy for single point was obtained with the E5 measurements with a DRMS (horizontal root mean square error) of 4.57 m. For E1/L1 frequency, the 2DRMS was 5.36 m. However, the Xiaomi Mi 8, thanks to the absence of the duty cycle, provided carrier phase measurements used for a static single frequency relative positioning with an achieved 2DRMS of 1.02 and 1.95 m in low and high multipath sites, respectively

Precise point positioning with single and dual-frequency multi-GNSS android smartphones

The new generation of Android smartphones is equipped with high performance Global Navigation Satellite System (GNSS) chips capable of tracking dual frequency multi-constellation data. Moreover, starting from version 9 of Android users can disable the duty cycle power saving option thus good quality pseudorange and carrier phase raw data are available thus the application of Precise Point Positioning (PPP) algorithm becomes more and more interesting. The main aim of this work is to assess the PPP performance of the first dual-frequency GNSS smartphone produced by Xiaomi equipped with a Broadcom BCM47755. The advantage of acquire dual frequency data is highlighted by comparing the performance obtained by Xiaomi with that of a single frequency smartphone the Samsung S8. The horizontal and vertical accuracy achieved by Xiaomi are of 0.51 m and 6 m respectively while those achieved by Samsung are 5.64 m for 15 m for horizontal and vertical

Analytic philosophy for biomedical research: the imperative of applying yesterday's timeless messages to today's impasses

The mantra that "the best way to predict the future is to invent it" (attributed to the computer scientist Alan Kay) exemplifies some of the expectations from the technical and innovative sides of biomedical research at present. However, for technical advancements to make real impacts both on patient health and genuine scientific understanding, quite a number of lingering challenges facing the entire spectrum from protein biology all the way to randomized controlled trials should start to be overcome. The proposal in this chapter is that philosophy is essential in this process. By reviewing select examples from the history of science and philosophy, disciplines which were indistinguishable until the mid-nineteenth century, I argue that progress toward the many impasses in biomedicine can be achieved by emphasizing theoretical work (in the true sense of the word 'theory') as a vital foundation for experimental biology. Furthermore, a philosophical biology program that could provide a framework for theoretical investigations is outlined

Use of the sensors of a latest generation mobile phone for the three-dimensional reconstruction of an archaeological monument: the survey of the Intihuatana stone in Machu Picchu (Peru’)

Abstract The survey of archaeological monuments presents particular needs and difficulties. Such surveys must in fact be as complete, geometrically correct and accurately geo-referenced as possible. These needs, however, often face problems of difficult accessibility, the need for rapid timing and complex logistical conditions. The latest generation of mobile phones are equipped with ultra-high resolution cameras up to 100 megapixel. Although they do not have the geometric characteristics of professional cameras, they can be used advantageously for the reconstruction of three-dimensional models using Structure from Motion methodologies . At the same time, the latest mobile phones are equipped with GPS/GNSS chips that allow a postprocessing of their positioning allowing to reach decimetric/centimetric accuracies. The use of sensors integrated in a mobile phone greatly simplify the survey both in terms of transportability but also in terms of authorizations by the competent authorities as the equipment is exactly the same that most tourists who visit the sites themselves bring with them. The approach proposed and made possible by these combined features in a latest generation mobile phone have been tested for a rapid survey of the Intihuatana stone in Machu Picchu (Peru), a site with considerable logistical and organizing complexity

Ex vivo characterization of acute myeloid leukemia patients undergoing hypomethylating agents and venetoclax regimen reveals a venetoclax-specific effect on non-suppressive regulatory T cells and bona fide PD-1+TIM3+ exhausted CD8+ T cells

Acute myeloid leukemia (AML) is an aggressive heterogeneous disease characterized by several alterations of the immune system prompting disease progression and treatment response. The therapies available for AML can affect lymphocyte function, limiting the efficacy of immunotherapy while hindering leukemia-specific immune reactions. Recently, the treatment based on Venetoclax (VEN), a specific B-cell lymphoma 2 (BCL-2) inhibitor, in combination with hypomethylating agents (HMAs) or low-dose cytarabine, has emerged as a promising clinical strategy in AML. To better understand the immunological effect of VEN treatment, we characterized the phenotype and immune checkpoint (IC) receptors' expression on CD4(+) and CD8(+) T cells from AML patients after the first and second cycle of HMA in combination with VEN. HMA and VEN treatment significantly increased the percentage of na & iuml;ve CD8(+) T cells and TIM-3(+) CD4(+) and CD8(+) T cells and reduced cytokine-secreting non-suppressive T regulatory cells (Tregs). Of note, a comparison between AML patients treated with HMA only and HMA in combination with VEN revealed the specific contribution of VEN in modulating the immune cell repertoire. Indeed, the reduction of cytokine-secreting non-suppressive Tregs, the increased TIM-3 expression on CD8(+) T cells, and the reduced co-expression of PD-1 and TIM-3 on both CD4(+) and CD8(+) T cells are all VEN-specific. Collectively, our study shed light on immune modulation induced by VEN treatment, providing the rationale for a novel therapeutic combination of VEN and IC inhibitors in AML patients

Solutions and limitations of the geomatic survey of an archaeological site in hard to access areas with a latest generation smartphone: the example of the Intihuatana stone in Machu Picchu (Peru)

Archaeological remains need to be geometrically surveyed and set in absolute reference systems in order to allow a "virtual visit" and to create "digital twins" useful in case of deterioration for proper restoration. Some countries (e.g., Peru) have a vast archaeological heritage whose survey requires optimized procedures that allow high productivity while maintaining high standards of geometric accuracy. A large part of Peru's cultural heritage is located in remote areas, at high altitudes and not easily accessible. For this reason, it is of great interest to study the possible applications of easily transportable instruments. In this study it was verified how the capabilities of the latest smartphones in terms of absolute differential positioning and photogrammetric acquisition can allow the acquisition of a geometrically correct and georeferenced three-dimensional model. The experimentation concerned a new survey of the Intihuatana stones at Machu Picchu and its comparison with a previous survey carried out with a much more complex laser scanning instrumentation. It is important to note that both the photogrammetric survey and the GPS/GNSS survey were carried out with the same smartphone taking full advantage of both features of the same mobile phone. Relative comparison to an existing point cloud provided differences of 2 millimeters in mean with an RMSE of 2 cm. The absolute positioning accuracy compared to a very large-scale cartography appears to be of the order of one metre as was expected mainly due to the high distance of the GPS/GNSS permanent stations

Prexasertib, a Chk1/Chk2 inhibitor, increases the effectiveness of conventional therapy in B-/T- cell progenitor acute lymphoblastic leukemia

During the last few years many Checkpoint kinase 1/2 (Chk1/Chk2) inhibitors have been developed for the treatment of different type of cancers. In this study we evaluated the efficacy of the Chk 1/2 inhibitor prexasertib mesylate monohydrate in B-/T- cell progenitor acute lymphoblastic leukemia (ALL) as single agent and in combination with other drugs. The prexasertib reduced the cell viability in a dose and time dependent manner in all the treated cell lines. The cytotoxic activity was confirmed by the increment of apoptotic cells (Annexin V/Propidium Iodide staining), by the increase of \u3b3H2A.X protein expression and by the activation of different apoptotic markers (Parp-1 and pro-Caspase3 cleavage). Furthermore, the inhibition of Chk1 changed the cell cycle profile. In order to evaluate the chemo-sensitizer activity of the compound, different cell lines were treated for 24 and 48 hours with prexasertib in combination with other drugs (imatinib, dasatinib and clofarabine). The results from cell line models were strengthened in primary leukemic blasts isolated from peripheral blood of adult acute lymphoblastic leukemia patients. In this study we highlighted the mechanism of action and the effectiveness of prexasertib as single agent or in combination with other conventional drugs like imatinib, dasatinib and clofarabine in the treatment of B-/T-ALL

Prevention of incisional hernia post emergency laparotomy: A time to change? A case series.

Introduction: Complicated acute diverticulitis (CAD) is a surgical challenge in which a mini-invasive approach may be offered. Laparoscopic peritoneal lavage (LPL) was introduced as an alternative to sigmoid resection. However, the role of LPL is still under debate. Aim of this study was to evaluate which surgical strategy between LPL and Laparoscopic Sigmoidectomy (LS) could give better outcomes in CAD. Materials and methods: This prospective, observational, multicenter study lasted from 2015 until to 2018. Inclusion criteria: left colonic or sigmoid CAD (modified Hinchey’’s classification: grade II not responder to conservative treatment and grade III). Exclusion criteria: septic shock, immunodepression, previous multiple surgical operations, modified Hinchey’’s grade I and IV,\15 and[85 years. Comparisons were made between LPL and LS groups. Results: 66 patients were enrolled: 28 (42%) had LPL and 38 (58%) LS. Following sigmoidectomy, 24 pts (63%) had a primary anastomosis and 14 pts (37%) an end-colostomy (Hartmann’’s procedure). There were no significant differences regarding age, male gender rate and mean BMI (p = 0.314, p = 0.07, p = 0.129, respectively). ASA score [2 was significantly higher in LPL (p = 0.05). The number of previous episodes of diverticulitis and the mean C-Reactive Protein dosage were similar (p = 0.756 and 0.846). Mannheim Peritonitis Index was significantly higher in LPL (0.004). No differences were found regarding to the distribution of Hinchey’’s grades II and III (p = 0.727). 1 (4%) patient in LPL and 5 pts (13%) in LS needed a conversion to open surgery (p = 0.181). Overall, the morbidity rates were 33% in LPL and 18% in LS (p = 0.169). Organ space infection (30% vs 3%, p = 0.002) and the re-operation rates (18.5% vs 0; p = 0.006) resulted significantly higher in the LPL group. Mortality was nihil. Mean post-op length of stay was 11.4 days in LPL and 8.23 days in LS (p = 0.088). Diverticular recurrence was significantly increased in LPL (p = 0.003). Conclusions: Compared to LS, LPL is associated with increased ongoing sepsis, emergency re-intervention and recurrence of acute diverticulitis. The role of LPL for patients with CAD remains questionabl