Physicists have long wondered whether the gravitational interactions between matter and antimatter might be different from those between matter and itself. Although there are many indirect ...indications that no such differences exist and that the weak equivalence principle holds, there have been no direct, free-fall style, experimental tests of gravity on antimatter. Here we describe a novel direct test methodology; we search for a propensity for antihydrogen atoms to fall downward when released from the ALPHA antihydrogen trap. In the absence of systematic errors, we can reject ratios of the gravitational to inertial mass of antihydrogen >75 at a statistical significance level of 5%; worst-case systematic errors increase the minimum rejection ratio to 110. A similar search places somewhat tighter bounds on a negative gravitational mass, that is, on antigravity. This methodology, coupled with ongoing experimental improvements, should allow us to bound the ratio within the more interesting near equivalence regime.
The hydrogen atom is one of the most important and influential model systems in modern physics. Attempts to understand its spectrum are inextricably linked to the early history and development of ...quantum mechanics. The hydrogen atom's stature lies in its simplicity and in the accuracy with which its spectrum can be measured and compared to theory. Today its spectrum remains a valuable tool for determining the values of fundamental constants and for challenging the limits of modern physics, including the validity of quantum electrodynamics and--by comparison with measurements on its antimatter counterpart, antihydrogen--the validity of CPT (charge conjugation, parity and time reversal) symmetry. Here we report spectroscopy of a pure antimatter atom, demonstrating resonant quantum transitions in antihydrogen. We have manipulated the internal spin state of antihydrogen atoms so as to induce magnetic resonance transitions between hyperfine levels of the positronic ground state. We used resonant microwave radiation to flip the spin of the positron in antihydrogen atoms that were magnetically trapped in the ALPHA apparatus. The spin flip causes trapped anti-atoms to be ejected from the trap. We look for evidence of resonant interaction by comparing the survival rate of trapped atoms irradiated with microwaves on-resonance to that of atoms subjected to microwaves that are off-resonance. In one variant of the experiment, we detect 23 atoms that survive in 110 trapping attempts with microwaves off-resonance (0.21 per attempt), and only two atoms that survive in 103 attempts with microwaves on-resonance (0.02 per attempt). We also describe the direct detection of the annihilation of antihydrogen atoms ejected by the microwaves.
The bioartificial kidney (BAK) aims at improving dialysis by developing 'living membranes' for cells-aided removal of uremic metabolites. Here, unique human conditionally immortalized proximal tubule ...epithelial cell (ciPTEC) monolayers were cultured on biofunctionalized MicroPES (polyethersulfone) hollow fiber membranes (HFM) and functionally tested using microfluidics. Tight monolayer formation was demonstrated by abundant zonula occludens-1 (ZO-1) protein expression along the tight junctions of matured ciPTEC on HFM. A clear barrier function of the monolayer was confirmed by limited diffusion of FITC-inulin. The activity of the organic cation transporter 2 (OCT2) in ciPTEC was evaluated in real-time using a perfusion system by confocal microscopy using 4-(4-(dimethylamino)styryl)-N-methylpyridinium iodide (ASP(+)) as a fluorescent substrate. Initial ASP(+) uptake was inhibited by a cationic uremic metabolites mixture and by the histamine H2-receptor antagonist, cimetidine. In conclusion, a 'living membrane' of renal epithelial cells on MicroPES HFM with demonstrated active organic cation transport was successfully established as a first step in BAK engineering.
Sequence similarity and profile searching tools were used to analyze the genome sequences of Arabidopsis thaliana, Saccharomyces cerevisiae, Schizosaccharomyces pombe, Caenorhabditis elegans and ...Drosophila melanogaster for genes encoding three families of histone deacetylase (HDAC) proteins and three families of histone acetyltransferase (HAT) proteins. Plants, animals and fungi were found to have a single member of each of three subfamilies of the GNAT family of HATs, suggesting conservation of these functions. However, major differences were found with respect to sizes of gene families and multi‐domain protein structures within other families of HATs and HDACs, indicating substantial evolutionary diversification. Phylogenetic analysis identified a new class of HDACs within the RPD3/HDA1 family that is represented only in plants and animals. A similar analysis of the plant‐specific HD2 family of HDACs suggests a duplication event early in dicot evolution, followed by further diversification in the lineage leading to Arabidopsis. Of three major classes of SIR2‐type HDACs that are found in animals, fungi have representatives only in one class, whereas plants have representatives only in the other two. Plants possess five CREB‐binding protein (CBP)‐type HATs compared with one to two in animals and none in fungi. Domain and phylogenetic analyses of the CBP family proteins showed that this family has evolved three distinct types of CBPs in plants. The domain architecture of CBP and TAFII250 families of HATs show significant differences between plants and animals, most notably with respect to bromodomain occurrence and their number. Bromodomain‐containing proteins in Arabidopsis differ strikingly from animal bromodomain proteins with respect to the numbers of bromodomains and the other types of domains that are present. The substantial diversification of HATs and HDACs that has occurred since the divergence of plants, animals and fungi suggests a surprising degree of evolutionary plasticity and functional diversification in these core chromatin components.
Abstract Hypersensitivity reactions (HSR) are frequently reported in patients rechallenged with carboplatin for recurrent ovarian cancer (ROC) and represent a critical issue, since discontinuation of ...the platinum-based therapy could affect prognosis. Several strategies to allow platinum rechallenge have been described, with controversial outcomes. The aim of this study is to illustrate a 10-year experience with cisplatin in patients with a previous HSR to carboplatin or at risk for allergy. A retrospective review of all patients with platinum sensitive ROC retreated with carboplatin was performed between January 2007 and May 2016 at the Istituto Nazionale Tumori, Fondazione “G. Pascale”, Naples. Among 183 patients, 49 (26.8%) presented HSR to carboplatin, mainly during second line therapy. Mean number of cycles before HSR was 8 (range 3–17). G2, G3 and G4 reaction were detected in 83%, 15% and 2% of patients, respectively. In a multivariate analysis including age, hystotype, BRCA status, previous known HSR, and combination drug administered, only the type of carboplatin-based doublet used as 2nd line therapy was found to significantly affect HSR development, with a protective effect of PLD (pegylated liposomal doxorubicin) (p = 0.014, OR = 0.027). Thirty seven patients (77%) with a previous HSR to carboplatin were rechallenged with cisplatin. Treatment was generally well tolerated. 5 patients (13.1%) experienced mild HSR to cisplatin, successfully managed in all cases. 14 patients were treated with cisplatin even without a carboplatin-related HSR due to other allergies. Among these, only one developed HSR (7.1%). Cisplatin rechallenge is a feasible approach in patients experiencing HSR to carboplatin to maintain the beneficial effect of platinum while reducing hypersensitivity-related risks.
The properties of antihydrogen are expected to be identical to those of hydrogen, and any differences would constitute a profound challenge to the fundamental theories of physics. The most commonly ...discussed antiatom-based tests of these theories are searches for antihydrogen-hydrogen spectral differences (tests of CPT (charge-parity-time) invariance) or gravitational differences (tests of the weak equivalence principle). Here we, the ALPHA Collaboration, report a different and somewhat unusual test of CPT and of quantum anomaly cancellation. A retrospective analysis of the influence of electric fields on antihydrogen atoms released from the ALPHA trap finds a mean axial deflection of 4.1 ± 3.4 mm for an average axial electric field of 0.51 V mm(-1). Combined with extensive numerical modelling, this measurement leads to a bound on the charge Qe of antihydrogen of Q=(-1.3 ± 1.1 ± 0.4) × 10(-8). Here, e is the unit charge, and the errors are from statistics and systematic effects.
This study describes the synthesis of Cu/Nb
2
O
5
, Fe/Nb
2
O
5
, and Cu-Fe/Nb
2
O
5
catalysts obtained by incorporating copper and/or iron metals into niobium pentoxide (Nb
2
O
5
). The new ...materials were characterized by the following techniques: Thermogravimetric Analysis (TA), surface and pore analysis, X-ray diffractometry (XRD), and Fourier Transform Infrared Spectroscopy (FT-IR). The catalyst was applied in the photocatalytic degradation of salicylic acid (SA). The influence of different parameters (calcined temperature, pH, and metal addition) on the photocatalytic reaction was evaluated. The results indicated that catalysts containing copper were more active and pH influenced the SA degradation process. SA removal results indicated that Cu/Nb
2
O
5
photocatalyst presented a 1.5 fold higher degradation after 120 min in comparison to Cu-Fe/Nb
2
O
5
and 4.6 fold higher than Fe/Nb
2
O
5
catalyst, all them calcined at 400 °C. In tests carried out in the presence of formic acid, increasing the pH from about 3 to 7 allowed an almost 3.4-fold increase in SA degradation for the Cu-Fe/Nb
2
O
5
catalyst calcined at 400 °C.
In patients with recurrent ovarian cancer, the choice of second-line therapy is complex. Several factors have to be considered, such as platinum-free interval (PFI), residual toxicity from the ...previous treatments, BRCA1/2 gene mutation status. Trebectedin is a minor groove DNA binder derived from a marine organism that has shown efficacy in different settings in ovarian cancer therapy. It has been approved in the treatment of partially platinum sensitive (PPS) (PFI between 6 and 12 months) relapsed ovarian cancer according to the statistically significant progression-free survival (7.3 versus 5.8 months) and overall survival (22.2 versus 18.9 months) benefit compared with single-agent pegylated liposomal doxorubicin (PLD) in the OVA 301 phase III trial. This drug has been shown to prolong the time to first subsequent treatment and improve the efficacy of further platinum-based chemotherapy. The role of trabectedin/PLD followed by platinum combination compared with the reverse sequence in PPS is actually in evaluation in the INOVATYON phase III study, which will clarify the best sequence to be adopted in this setting. Trabectedin has been shown to be active in patient carriers of BRCA mutations, probably for its mechanism of action directly affecting DNA and it is actually tested as a single agent in some phase III trials in BRCA mutated and BRCAness ovarian cancer patients. Trabectedin is also active on the immune system. There is, therefore, the rational for new trials of a combination with immune checkpoint inhibitors.
MITO-8 showed that prolonging platinum-free interval by introducing non-platinum-based chemotherapy (NPBC) does not improve prognosis of patients with partially platinum-sensitive recurrent ovarian ...cancer. Quality of life (QoL) was a secondary outcome.
Ovarian cancer patients recurring or progressing 6–12months after previous platinum-based chemotherapy (PBC) were randomized to receive PBC or NPBC as first treatment. QoL was assessed at baseline, third and sixth cycles, with the EORTC C-30 and OV-28 questionnaires. Mean changes and best response were analysed. Progression-free survival, response rate, and toxicity are also reported for proper interpretation of data. All analyses were based on intention-to-treat.
Out of the 215 patients, 151 (70.2%) completed baseline questionnaire, balanced between the arms; thereafter, missing rate was higher in the NPBC arm. At mean change analysis, C30 scores were prevalently worse in the NPBC than PBC arm, statistical significance being attained for emotional functioning, global health status/QoL, fatigue, and dyspnoea (effect sizes ranging from 0.30 to 0.51). Conversely, as for OV28 scale, the other chemotherapy side-effects item was significantly worse with PBC at three and six cycles, with a larger effect size (0.70 and 0.54, respectively). At best response analysis, improvement of emotional functioning and pain and worsening of peripheral neuropathy and other chemotherapy side-effects were significantly more frequent in the PBC arm. Progression-free survival (median 9 versus 5months, P=0.001) and objective response rate (51.6% versus 19.4%, P=0.0001) were significantly better with PBC. Allergy, blood cell count, alopecia, nausea, musculoskeletal, and neurological side-effects were more frequent and severe with PBC; hand–foot skin reaction, rash/desquamation, mucositis, and vascular events were more frequent with NPBC.
MITO-8 QoL analysis shows that deterioration of some functioning and symptom scales is lower with PBC, with improvement of emotional functioning and pain, despite worsening of toxicity-related items.
NCT00657878.
We demonstrate a novel detection method for the cyclotron resonance frequency of an electron plasma in a Penning-Malmberg trap. With this technique, the electron plasma is used as an in situ ...diagnostic tool for the measurement of the static magnetic field and the microwave electric field in the trap. The cyclotron motion of the electron plasma is excited by microwave radiation and the temperature change of the plasma is measured non-destructively by monitoring the plasma's quadrupole mode frequency. The spatially resolved microwave electric field strength can be inferred from the plasma temperature change and the magnetic field is found through the cyclotron resonance frequency. These measurements were used extensively in the recently reported demonstration of resonant quantum interactions with antihydrogen.
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