To send content items to your account,
please confirm that you agree to abide by our usage policies.
If this is the first time you use this feature, you will be asked to authorise Cambridge Core to connect with your account.
Find out more about sending content to .
To send content items to your Kindle, first ensure firstname.lastname@example.org
is added to your Approved Personal Document E-mail List under your Personal Document Settings
on the Manage Your Content and Devices page of your Amazon account. Then enter the ‘name’ part
of your Kindle email address below.
Find out more about sending to your Kindle.
Note you can select to send to either the @free.kindle.com or @kindle.com variations.
‘@free.kindle.com’ emails are free but can only be sent to your device when it is connected to wi-fi.
‘@kindle.com’ emails can be delivered even when you are not connected to wi-fi, but note that service fees apply.
The use of statistical/machine learning (ML) approaches to materials science is experiencing explosive growth. Here, we review recent work focusing on the generation and application of libraries from both experiment and theoretical tools. The library data enables classical correlative ML and also opens the pathway for exploration of underlying causative physical behaviors. We highlight key advances facilitated by this approach and illustrate how modeling, macroscopic experiments, and imaging can be combined to accelerate the understanding and development of new materials systems. These developments point toward a data-driven future wherein knowledge can be aggregated and synthesized, accelerating the advancement of materials science.
Background: Micrographia is a rare neurological finding in isolation. Most cases of isolated micrographia have been found in association with focal ischemia of the left basal ganglia. Methods: We present a case of post-traumatic micrographia stemming from contusion to the left basal ganglia. We performed a detailed analysis of the patient’s writing at three-year follow-up. Results: A halthy 15 year old male was admitted following a BM accident. CT showed contusion to the left basall ganglia/external capsule. MRI was negative for underlying lesion. He had a short stay in the ICU and then was discharged. Two years later, he expressed concern regarding difficulty with sma, cramped writing at school. Writing analysis revealed micrographia with spontaneous printing as well as printing to dictation, but not with copied English nor Japanese writing. Conclusions: Isolated micrographia is a rare neurological finding. We present the incidence of this symptom folllowing gliding contusion to the et basal ganglia and external capsule.
Coupling superconductors to quantum Hall edge states is the subject of intense investigation as part of the ongoing search for non-abelian excitations. Our group has previously observed supercurrents of hundreds of picoamperes in graphene Josephson junctions in the quantum Hall regime. One of the explanations of this phenomenon involves the coupling of an electron edge state on one side of the junction to a hole edge state on the opposite side. In our previous samples, these states are separated by several microns. Here, a narrow trench perpendicular to the contacts creates counterpropagating quantum Hall edge channels tens of nanometres from each other. Transport measurements demonstrate a change in the low-field Fraunhofer interference pattern for trench devices and show a supercurrent in both trench and reference junctions in the quantum Hall regime. The trench junctions show no enhancement of quantum Hall supercurrent and an unexpected supercurrent periodicity with applied field, suggesting the need for further optimization of device parameters.
Background: Inflicted head injury is a major cause of infant morbidity and mortality. The extent of traumatic brain injury in infants is often best characterized by diffusion weighted magnetic resonance imaging. In this cases series we describe four infants aged 6-19 months, with small unilateral subdural hematomas secondary to abusive head trauma accompanied by extensive areas of restricted diffusion weighted imaging isolated to the cerebral white matter. Methods: Retrospective, single-centre case series of four children with small unilateral subdural hematomas with early and delayed MR imaging with diffusion weighted imaging. Results: In three cases there was acute diffusion restriction ispilateral to the subdural, while in one case diffusion restriction was present bilaterally. All patients had multiple seizures and bilateral multilayered retinal hemorrhages. After non-surgical treatment, all patients survived albeit with significant motor and cognitive deficits and significant cortical atrophy on long-term followup imaging. Conclusions: These four cases highlight that relatively small subdural hematomas following child abuse can manifest with extensive white matter injury only evident at early stages with diffusion weighted imaging. We propose that selective white matter injury as a result of either reperfusion or axonal degeneration in response to the initial insult accounts for this novel pattern of infantile traumatic brain injury.
Background: Ciliary mutations cause multi-system disorders, often involving the CNS. We set to evaluate the prevalence of ciliary dysfunction in children with isolated neuroanatomical defects, by measuring nasal nitric oxide (nNO), a screening test for Primary Ciliary Dyskinesia (PCD). Study design: We measured nNO levels of 26 children with congenital midline CNS defects. We evaluated the effect of age, gender, and anomaly (brain, spinal cord, or combined) on measurements. We compared our results to the previously established normal range (153.6-509.9 nL/min), and to the cutoff for PCD (77 nL/min). Results: The range for nNO in our cohort was 56.5-334.7 nL/min, with age, gender, and anomaly not having a significant effect. The overall mean, 217.7 nL/min, was significantly lower than that of normal children, 314.51 nL/min (p<0.01). Four subjects (15.4%) had nNO levels below the lower end of normal, with two (7.7%) having values fitting the cutoff for PCD. Conclusions: We report an association between ciliary dysfunction and isolated midline neuroanatomical defects, not in context of any known syndrome. This suggests that genes causing isolated CNS defects, may be implied in the function of cilia. Longitudinal studies are required to investigate whether children with abnormal measurements suffer from any respiratory sequelae.
Stage separation is a critical technical issue for developing two-stage-to-orbit (TSTO) launch systems with widebody carrier aircraft that use air-breathing propulsion and launch vehicle stages that use rocket propulsion. During conceptual design phases, this issue can be addressed with a combination of engineering methods, computational fluid dynamics simulations, and trajectory analysis of the mated system and the launch vehicle after staging. The outcome of such analyses helps to establish the credibility of the proposed TSTO system and formulate a ground-based test programme for the preliminary design phase. This approach is demonstrated with an assessment of stage separation from the shuttle carrier aircraft. Flight conditions are determined for safe mated flight, safe stage separation, and for the launch vehicle as it commences ascending flight. Accurate assessment of aerodynamic forces and moments is critical during staging to account for interference effects from the proximities of the two large vehicles. Interference aerodynamics have a modest impact on the separation conditions and separated flight trajectories, but have a significant impact on the interaction forces.
We report on the effect of the International Nosocomial Infection Control Consortium's (INICC) multidimensional approach for the reduction of ventilator-associated pneumonia (VAP) in adult patients hospitalized in 21 intensive-care units (ICUs), from 14 hospitals in 10 Indian cities. A quasi-experimental study was conducted, which was divided into baseline and intervention periods. During baseline, prospective surveillance of VAP was performed applying the Centers for Disease Control and Prevention/National Healthcare Safety Network definitions and INICC methods. During intervention, our approach in each ICU included a bundle of interventions, education, outcome and process surveillance, and feedback of VAP rates and performance. Crude stratified rates were calculated, and by using random-effects Poisson regression to allow for clustering by ICU, the incidence rate ratio for each time period compared with the 3-month baseline was determined. The VAP rate was 17·43/1000 mechanical ventilator days during baseline, and 10·81 for intervention, showing a 38% VAP rate reduction (relative risk 0·62, 95% confidence interval 0·5–0·78, P = 0·0001).
Infection surveillance definitions for long-term care facilities (ie, the McGeer Criteria) have not been updated since 1991. An expert consensus panel modified these definitions on the basis of a structured review of the literature. Significant changes were made to the criteria defining urinary tract and respiratory tract infections. New definitions were added for norovirus gastroenteritis and Clostridum difficile infections.
Atypical teratoid/rhabdoid tumor (AT/RT) is a highly malignant tumor of the central nervous system. Its pathogenesis remains unknown. Like glioblastomas, AT/RTs contain brain cancer stem cells (CSCs) that suppress the immunity of patients and are resistant to conventional chemotherapy and radiation therapy. Considerable infiltration of immune cells, including macrophages/microglia, dendritic cells and T-cells, has been noted in glioblastomas, which correlates with poor prognosis. The present study examines the significance of infiltrating immune cells in four cases of AT/RT; including one associated with an autoimmune disease, Henoch-Schonlein purpura.
Tumor tissues from four patients with AT/RT were analyzed and compared with those from four patients with glioblastomas. The frequency of immune cells, including CD68+, CD4+, and CD8+ cells, was assessed by scoring for statistical analysis.
The infiltration of immune cells was identified in the case of AT/RT associated with HSP and three other cases of infratentorial AT/RTs. Moderate infiltration of CD68+ macrophages/microglia and CD4+ cells was noted in AT/RTs with no significant difference from that in glioblastomas (p > 0.05). However, the infiltration of CD8+ T-cells was significantly higher in AT/RTs than that in glioblastomas (p < 0.05); CD4+/CD8+ ratio was significantly lower in AT/RTs than that in glioblastomas (p < 0.05). In addition, eosinophils were found in all AT/RTs, but not in glioblastomas.
These findings suggest an immune microenvironment of AT/RTs with more immune effectors than glioblastomas. Our observation contributes to understanding the growth environment of AT/RTs for which adjuvant immunotherapy may be potentially beneficial.
We prove in this paper that on a non-singular projective variety, the χ-semistable functor is proper and the χ-stable functor is separated. This result was proved for μ-stability and μ-semistability by Langton. An essential part of our proof consists in defining a notion of stability between the μ and χ definitions and then proceeding by induction.
The lattice deformation caused by 100 MeV Ti7+ ion irradiation in Si (100) has been studied using X-ray topographic techniques. An important finding is the appearance of a strain field perpendicular to the ion beam direction in the irradiated region well separated from the projected range of implanted ions. This in-plane strain extends in the bulk of the sample and is not merely confined to the surface. The implanted region has been found to experience an out of plane strain which is expected to be tensile in nature.
CdSexTe1-x nanoparticles (with different stoichiometry ratio x) dispersed in silicon dioxide films have been grown by magnetron sputtering technique followed by thermal annealing. Effect of thermal annealing conditions on the structural, compositional, optical and electronic properties of nanoparticles has been studied using GAXRD, XPS, TEM, and spectroscopic ellipsometry techniques. A structural transformation in the nanoparticle core mediated purely by surface layer effects in the case of CdTe and a spontaneous self-organization of nanoparticles into nanorods in the case of CdSe via fractal growth has been observed. Preliminary observations from the ellipsometry measurements carried out on some of these nanoparticle films shows a blue shift of absorption edge.
High-κ dielectrics based the oxide of Al were prepared by atomic layer deposition (ALD) on 200-mm p-type Si wafers. Films were deposited directly on clean Si or on 0.5-nm underlayers of rapid thermal oxide or oxynitrides grown in O2 and/or NO ambients. The purpose of the underlayer films is to provide a barrier for atomic diffusion from the crystal Si to the high-κ dielectric film. Deposited Al-oxide films varied in thickness from 2 to 6 nm. Post deposition anneals were used to stabilize the ALD oxides. Equivalent SiO2-oxide thickness varied from 1.0 to 3.5 nm. In situ P-doped amorphous-Si 160 nm films were deposited over the oxides to prepare heavily doped n-type gate electrodes in MOS structures. Samples were rapid thermal annealed in N2 ambient at 800°C for 30 s, or spike annealed at 950, 1000, and 1050°C (nominally zero time at peak temperature). Flat band voltages, VFB were determined from C-V measurements on dot patterns. The 800°C anneals were used as a baseline, at which the poly-Si electrodes are crystallized and acquire electrical activation while subjecting the high-κ dielectrics to a low thermal budget. Positive shifts in VFB were observed, relative to a pure SiO2 control, ranging from 0.2 to 0.8 V. Spike annealing reduces the VFB shift for ALD films deposited over underlayer films. The VFB shift and the changes with annealing temperature show systematic dependence on the nitridation of the underlayer.
We show here that at a certain externally applied static magnetic field of
moderate value, photonic band gap (PBG) is induced at optical frequencies in
a stable colloidal dispersion containing a mixture of micron and nano sized
magnetite spheres. The PBG is found to depend on the size of microspheres
and is observed for only TM mode of the incident waves. Effect of
nonmagnetic doping on the PBG is also discussed. The observed effects are
attributed to the magnetically induced morphological dependent resonance
(MDR) in the micron sized magnetic spheres. The technique to induce PBG may
be easily amenable for lab-on-chip devices.
Genetic structure of five populations of a locally common rice (Oryza sativa L.) landrace Jaulia from parts of Uttarakhand state of India was studied using sequence tagged microsatellite site (STMS) markers. Of these, four populations were on-farm managed, assembled from different niche environments, and one population was conserved ex situ and represented static conservation. The 16 STMS primer pairs fully differentiated the inter- and intrapopulation diversity. A total of 72 alleles were recorded with a mean of 4.5 alleles per locus. Population wise, the total number of alleles ranged from 21 to 41, with maximum number of alleles for population IC 548358 and minimum number of alleles for population IC 100051 representing static conservation. A greater number of alleles specific to populations under farmer management could be recorded. Changes in yield parameters also seemed to be affected under farmer management besides other environmental adaptations for qualitative morphological characters. The marker diversity using STMS primer pairs indicates the genetic differentiation among populations resulting from joint effects of several evolutionary forces operating within the historical and biological context of the crop landrace. The variations in adaptations, on the other hand, indicate the degree to which populations are adapted to their environments and their potential for continued performance or as donors of characters in plant breeding. Both biotic and abiotic aspects of the environment are involved.