Capacitive vs piezoresistive MEMS gyroscopes: a theoretical and experimental noise comparison

AbstractThis work aims both at theoretically formalizing a comparison between piezoresistive (PZR) and capacitive (CAP) gyroscopes in terms of resolution limits, and at validating the predictions through experimental measurements on MEMS devices of both types. As predicted by the developed theory, PZR gyroscopes, well immune to parasitic capacitances and void of feedback resistance noise, show 10-fold better angle random walk (ARW) than CAP gyroscopes for the same nominal mode-split value, the same drive-motion amplitude and the same electronic noise density

Fotografiar(se): relatos de un taller de comunicación comunitaria y fotografía con niñes de una escuela primaria de La Plata

En el contexto de una cotidianeidad escolar signada por las dificultades de encontrarse “sin escuela” se desarrolló un taller de comunicación comunitaria y fotografía. El objetivo de este trabajo es relatar esa experiencia presentando sucesivamente la escuela, las inquietudes que guiaron la propuesta y su desarrollo. Describimos a lo largo del escrito algunas dificultades suscitadas en el proceso como así también ciertos hallazgos que nos posibilitan repensar lo transitado para forjar a partir de allí, nuevos espacios en la escuela con sus estudiantes y trabajadores. Este texto, que versa sobre el taller, habla también de la escuela, el barrio y las personas que les habitan. En ese sentido, se incorpora a la trama de relatos que vienen comunicando desde una pluralidad de voces -e imágenes- sobre cómo es la escuela (hoy “itinerante”) del barrio.Eje temático 4: Gestión de las políticas públicas e intervenciones profesionales.Grupo de trabajo 27: La cultura en el entramado de lo social. Reflexiones en torno a saberes y experiencias de intervención, enseñanza e investigación en/desde la dimensión cultural.Facultad de Trabajo Socia

Fotografiar(se): relatos de un taller de comunicación comunitaria y fotografía con niñes de una escuela primaria de La Plata

En el contexto de una cotidianeidad escolar signada por las dificultades de encontrarse “sin escuela” se desarrolló un taller de comunicación comunitaria y fotografía. El objetivo de este trabajo es relatar esa experiencia presentando sucesivamente la escuela, las inquietudes que guiaron la propuesta y su desarrollo. Describimos a lo largo del escrito algunas dificultades suscitadas en el proceso como así también ciertos hallazgos que nos posibilitan repensar lo transitado para forjar a partir de allí, nuevos espacios en la escuela con sus estudiantes y trabajadores. Este texto, que versa sobre el taller, habla también de la escuela, el barrio y las personas que les habitan. En ese sentido, se incorpora a la trama de relatos que vienen comunicando desde una pluralidad de voces -e imágenes- sobre cómo es la escuela (hoy “itinerante”) del barrio.Eje temático 4: Gestión de las políticas públicas e intervenciones profesionales.Grupo de trabajo 27: La cultura en el entramado de lo social. Reflexiones en torno a saberes y experiencias de intervención, enseñanza e investigación en/desde la dimensión cultural.Facultad de Trabajo Socia

Oligodendroglia are particularly vulnerable to oxidative damage after neurotrauma in vivo

Loss of function following injury to the central nervous system is worsened by secondary degeneration of neurons and glia surrounding the injury and initiated by oxidative damage. However, it is not yet known which cellular populations and structures are most vulnerable to oxidative damage in vivo Using Nanoscale secondary ion mass spectrometry (NanoSIMS), oxidative damage was semi-quantified within cellular subpopulations and structures of optic nerve vulnerable to secondary degeneration, following a partial transection of the optic nerve in adult female PVG rats. Simultaneous assessment of cellular subpopulations and structures revealed oligodendroglia as the most vulnerable to DNA oxidation following injury. 5-ethynyl-2'-deoxyuridine (EdU) was used to label cells that proliferated in the first 3 days after injury. Injury led to increases in DNA, protein and lipid damage in OPCs and mature oligodendrocytes at 3 days, regardless of proliferative state, associated with a decline in the numbers of OPCs at 7 days. O4+ pre-oligodendrocytes also exhibited increased lipid peroxidation. Interestingly, EdU+ mature oligodendrocytes derived after injury demonstrated increased early susceptibility to DNA damage and lipid peroxidation. However, EdU- mature oligodendrocytes with high 8OHdG immunoreactivity were more likely to be caspase3+. By day 28, newly derived mature oligodendrocytes had significantly reduced MYRF mRNA indicating that the myelination potential of these cells may be reduced. The proportion of caspase3+ oligodendrocytes remained higher in EdU- cells. Innovative use of NanoSIMS together with traditional immunohistochemistry and in situ hybridisation have enabled the first demonstration of subpopulation specific oligodendroglial vulnerability to oxidative damage, due to secondary degeneration in vivo. SIGNIFICANCE STATEMENT. Injury to the central nervous system is characterised by oxidative damage in areas adjacent to the injury. However, the cellular subpopulations and structures most vulnerable to this damage remain to be elucidated. Here we use powerful NanoSIMS techniques to show increased oxidative damage in oligodendroglia and axons and to demonstrate that cells early in the oligodendroglial lineage are the most vulnerable to DNA oxidation. Further immunohistochemical and in situ hybridisation investigation reveals that mature oligodendrocytes derived after injury are more vulnerable to oxidative damage than their counterparts existing at the time of injury and have reduced MYRF mRNA, yet pre-existing oligodendrocytes are more likely to die

Oligodendroglia Are Particularly Vulnerable to Oxidative Damage After Neurotrauma In Vivo.

In the paper "Oligodendroglia are particularly vulnerable to oxidative damage after neurotrauma in vivo," we determined the extent of oxidative damage to specific cellular subpopulations and structures within regions vulnerable to secondary degeneration and assessed the effect this had on oligodendroglial function. Comparative assessment of oxidative damage demonstrated selective vulnerability of oligodendroglia, specifically oligodendrocyte progenitor cells (OPCs) to DNA oxidation in vivo. Immunohistochemical fate mapping along the oligodendroglial lineage showed a transient susceptibility of these cells to DNA oxidation, protein nitration, and lipid peroxidation, with mature oligodendrocytes derived immediately after injury more vulnerable to DNA oxidation than their counterparts existing at the time of injury or later derived. In situ hybridization demonstrated a reduction in myelin regulatory factor (MyRF) messenger RNA (mRNA) fluorescence in newly derived mature oligodendrocytes, suggesting a compromise in the production and maintenance of the myelin sheath in these cells. The data imply a deficit in the normal differentiation of OPCs to myelinating oligodendrocytes, associated with a transient increase in oxidative damage, which may contribute to the dysmyelinating phenotype seen at chronic time points after injury. Identifying and understanding the sources of this oxidative damage is integral for the development of therapeutic interventions for neurotrauma

Comparative assessment of phototherapy protocols for reduction of oxidative stress in partially transected spinal cord slices undergoing secondary degeneration

Background: Red/near-infrared light therapy (R/NIR-LT) has been developed as a treatment for a range of conditions, including injury to the central nervous system (CNS). However, clinical trials have reported variable or sub-optimal outcomes, possibly because there are few optimized treatment protocols for the different target tissues. Moreover, the low absolute, and wavelength dependent, transmission of light by tissues overlying the target site make accurate dosing problematic. Results: In order to optimize light therapy treatment parameters, we adapted a mouse spinal cord organotypic culture model to the rat, and characterized myelination and oxidative stress following a partial transection injury. The ex vivo model allows a more accurate assessment of the relative effect of different illumination wavelengths (adjusted for equal quantal intensity) on the target tissue. Using this model, we assessed oxidative stress following treatment with four different wavelengths of light: 450 nm (blue); 510 nm (green); 660 nm (red) or 860 nm (infrared) at three different intensities: 1.93 × 10¹⁶ (low); 3.85 × 10¹⁶ (intermediate) and 7.70 × 10¹⁶ (high) photons/cm²/s. We demonstrate that the most effective of the tested wavelengths to reduce immunoreactivity of the oxidative stress indicator 3-nitrotyrosine (3NT) was 660 nm. 860 nm also provided beneficial effects at all tested intensities, significantly reducing oxidative stress levels relative to control (p ≤ 0.05). Conclusions: Our results indicate that R/NIR-LT is an effective antioxidant therapy, and indicate that effective wavelengths and ranges of intensities of treatment can be adapted for a variety of CNS injuries and conditions, depending upon the transmission properties of the tissue to be treated.12 page(s

Endoscopic surgical procedures for cervical cancer treatment: a literature review

Cervical cancer remains the leading cause of death by gynecologic cancer worldwide, comprising 15% of all cancers in women younger than 40 years. Standard treatments of invasive cancer in early stages are radical hysterectomy and pelvic radiotherapy, both of which are almost reliable by minimal invasive surgery, so as traditional laparoscopy and robotic-assisted surgery. Moreover, 45% of reproductive-age women are diagnosed with stage IB1 disease, making the fertility-sparing procedure, radical trachelectomy, a viable option for most patients for treatment of early-stage cervical cancer and maintenance of future fertility. This chapter focuses on emerging surgical techniques, including the laparoscopic and robotic approach, are improving perioperative outcomes for these patients. A manual and computer-aided search was carried out for all reviews related to this topic, randomized controlled trials, prospective observational studies, retrospective studies and case reports published between 1980 and 2012, assessing robotic surgery, Search strings were: laparoscopic surgery; robot or robot-assisted surgery; radical hysterectomy; cervical cancer, minimally invasive surgery. Robotic-assisted gynecologic surgery has increased worldwide, considering the number of scientific articles dedicated to it though few retrospective and prospective studies have demonstrated the feasibility of robotic-assisted surgery in radical hysterectomy. In general, robot-assisted gynecologic surgery is often associated with longer operating room time but generally similar clinical outcomes, decreased blood loss, and shorter hospital stay. Robotic-assisted procedures are not, however, without their limitations: the equipment is still very large, bulky, and expensive, the staff must be trained, specifically on draping and docking the apparatus to maintain efficient operative times. Functional limitations include lack of haptic feedback, limited vaginal access, limited instrumentation, and larger port incisions. Exchanging instruments becomes more cumbersome and requires a surgical assistant to change the instruments. Additionally, the current robotic instruments do not include endoscopic staplers or vessel sealing devices. Finally, laparoscopic radical hysterectomy is a feasible and safe procedure that is associated with fewer intraoperative and postoperative complications than abdominal radical hysterectomy. The role of robotic-assisted surgery is continuing to expand, but well-designed, prospective studies with well-defined clinical, long-term outcomes, including complications, cost, pain, return to normal activity, and quality of life, are needed to fully assess the value of this new technology in radical hysterectomy. Scientific literature has shown the feasibility of a radical resection by minimally invasive oncological surgery and documented an equivalent number of pelvic nodes harvested by laparoscopy and open surgery. Women with a tumor size 2 cm or smaller and stage IA1 with lymphovascular space involvement (LVSI), IA2, or IB1 disease may be offered fertility-sparing treatment after thorough evaluation by an oncologist trained in this management

A water-filled garment to protect astronauts during interplanetary missions tested on board the ISS

Abstract As manned spaceflights beyond low Earth orbit are in the agenda of Space Agencies, the concerns related to space radiation exposure of the crew are still without conclusive solutions. The risk of long-term detrimental health effects needs to be kept below acceptable limits, and emergency countermeasures must be planned to avoid the short-term consequences of exposure to high particle fluxes during hardly predictable solar events. Space habitat shielding cannot be the ultimate solution: the increasing complexity of future missions will require astronauts to protect themselves in low-shielded areas, e.g. during emergency operations. Personal radiation shielding is promising, particularly if using available resources for multi-functional shielding devices. In this work we report on all steps from the conception, design, manufacturing, to the final test on board the International Space Station (ISS) of the first prototype of a water-filled garment for emergency radiation shielding against solar particle events. The garment has a good shielding potential and comfort level. On-board water is used for filling and then recycled without waste. The successful outcome of this experiment represents an important breakthrough in space radiation shielding, opening to the development of similarly conceived devices and their use in interplanetary missions as the one to Mars

Inflammation and blood-brain barrier breach remote from the primary injury following neurotrauma

Background: Following injury to the central nervous system, increased microglia, secretion of pro- and anti-inflammatory cytokines, and altered blood-brain barrier permeability, a hallmark of degeneration, are observed at and immediately adjacent to the injury site. However, few studies investigate how regions remote from the primary injury could also suffer from inflammation and secondary degeneration. Methods: Adult female Piebald-Viral-Glaxo (PVG) rats underwent partial transection of the right optic nerve, with normal, age-matched, unoperated animals as controls. Perfusion-fixed brains and right optic nerves were harvested for immunohistochemical assessment of inflammatory markers and blood-brain barrier integrity; fresh-frozen brains were used for multiplex cytokine analysis. Results: Immediately ventral to the optic nerve injury, immunointensity of both the pro-inflammatory biomarker inducible nitric oxide synthase (iNOS) and the anti-inflammatory biomarker arginase-1 (Arg1) increased at 7 days post-injury, with colocalization of iNOS and Arg1 immunoreactivity within individual cells. CD11b+ and CD45+ cells were increased 7 days post-injury, with altered BBB permeability still evident at this time. In the lower and middle optic tract and superior colliculus, IBA1+ resident microglia were first increased at 3 days; ED1+ and CD11b+ cells were first increased in the middle and upper tract and superior colliculus 7 days post-injury. Increased fibrinogen immunoreactivity indicative of altered BBB permeability was first observed in the contralateral upper tract at 3 days and middle tract at 7 days post-injury. Multiplex cytokine analysis of brain homogenates indicated significant increases in the pro-inflammatory cytokines, IL-2 and TNFa, and anti-inflammatory cytokine IL-10 1 day post-injury, decreasing to control levels at 3 days for TNFa and 7 days for IL-2. IL-10 was significantly elevated at 1 and 7 days post-injury with a dip at 3 days post-injury. Conclusions: Partial injury to the optic nerve induces a complex remote inflammatory response, characterized by rapidly increased pro- and anti-inflammatory cytokines in brain homogenates, increased numbers of IBA1+ cells throughout the visual pathways, and increased CD11b+ and ED1+ inflammatory cells, particularly towards the synaptic terminals. BBB permeability can increase prior to inflammatory cell infiltration, dependent on the brain region