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To assess experience, physical infrastructure, and capabilities of high-level isolation units (HLIUs) planning to participate in a 2018 global HLIU workshop hosted by the US National Emerging Special Pathogens Training and Education Center (NETEC).
An electronic survey elicited information on general HLIU organization, operating costs, staffing models, and infection control protocols of select global units.
Setting and participants:
The survey was distributed to site representatives of 22 HLIUs located in the United States, Europe, and Asia; 19 (86%) responded.
Data were coded and analyzed using descriptive statistics.
The mean annual reported budget for the 19 responding units was US$484,615. Most (89%) had treated a suspected or confirmed case of a high-consequence infectious disease. Reported composition of trained teams included a broad range of clinical and nonclinical roles. The mean number of HLIU beds was 6.37 (median, 4; range, 2–20) for adults and 4.23 (median, 2; range, 1–10) for children; however, capacity was dependent on pathogen.
Responding HLIUs represent some of the most experienced HLIUs in the world. Variation in reported unit infrastructure, capabilities, and procedures demonstrate the variety of HLIU approaches. A number of technical questions unique to HLIUs remain unanswered related to physical design, infection prevention and control procedures, and staffing and training. These key areas represent potential focal points for future evidence and practice guidelines. These data are important considerations for hospitals considering the design and development of HLIUs, and there is a need for continued global HLIU collaboration to define best practices.
The drive to replace scarce and expensive Pt-based electrocatalysts for oxygen reduction reaction (ORR) has led to the development of a group of electrocatalysts composed of transition-metal ion centers coordinated with four nitrogen groups (M-N4). Among these, metal phthalocyanines (MPcs), due to low cost of preparation, highly conjugated structure as well as high thermal and chemical stability, have received a great interest. The catalytic activity of MPcs can be improved by employing conducting supports. Here, in this report, we have solvothermally synthesized graphene-supported zinc phthalocyanine nanostructures, and their ORR kinetics and mechanism have been investigated in neutral solution (pH = 7) by using the rotating disk electrode technique. The as-synthesized nanocomposite followed a 4e− reduction pathway. The onset potential (−0.04 V versus Ag/AgCl) found in this work can be comparable with other state-of-the-art material, demonstrating good performance in neutral solution. The fascinating performance leads the nanocomposite material toward future energy applications.
The anatomy of the membranous labyrinth within the vestibule has direct implications for surgical intervention. The anatomy of the otoliths has been studied, but there is limited information regarding their supporting connective tissue structures such as the membrana limitans in humans.
One guinea pig and 17 cadaveric human temporal bones were scanned using micro computed tomography, after staining with 2 per cent osmium tetroxide and preservation with Karnovsky's solution, with a resolution from 1 µm to 55 µm. The data were analysed using VGStudio Max software, rendered in three-dimensions and published in augmented reality.
In 50 per cent of ears, the membrana limitans attached directly to the postero-superior part of the stapes footplate. If attachments were present in one ear, they were present bilaterally in 100 per cent of cases.
Micro computed tomography imaging allowed three-dimensional assessment of the inner ear. Such assessments are important as they influence the surgical intervention and the evolution of future innovations.
P. Mukherjee, Department of Electrical and Computer Engineering, University of Maryland,
R. Tandon, Department of Electrical and Computer Engineering, University of Arizona,
S. Ulukus, Department of Electrical and Computer Engineering, University of Maryland
In this chapter, we will discuss how the quality and availability of channel state information (CSI) affects secrecy in wireless networks. In particular, we study how the delay in the availability of CSI affects secrecy in the context of the two-user broadcast channel with confidential messages. We adopt a secure degrees of freedom perspective and investigate various CSI scenarios, including cases when the availability of CSI at the transmitter varies across users and with time. We discuss how to leverage such variabilities in CSI for secrecy and highlight the differences between the optimal degrees of freedom with or without secrecy constraints.
The availability of channel state information at the transmitters (CSIT) plays a crucial role in securing wireless communication at the physical layer. Various well-known physical-layer security techniques such as coding for the fading wiretap channel [1–4], coding for the multiple-antenna wiretap channel [5–8], artificial noise injection , cooperative jamming [10, 11], cooperation for secrecy [12–18], secure signal alignment [19–22], and other related techniques rely upon the assumption of timely availability of precise CSIT; see also a recent review article in . In most practical scenarios, the channel gains are measured by the receivers and then fed back to the transmitters. The measurement and feedback process necessarily introduces imprecision and delay into the CSI. Motivated by this fact, in this chapter we explore the fundamental limits of physical layer security when the CSIT is imperfect. For concreteness, we will focus on a particular wireless network model: the multiple-input single-output (MISO) broadcast channel with confidential messages (BCCM). This effectively models practical systems such as a cellular downlink network where each user wants not only reliability but also confidentiality of the information intended for it.
The focus of this chapter is on the secure degrees of freedom (s.d.o.f.) region of the fading two-user MISO BCCM, in which the transmitter with two antennas has two confidential messages, one for each of the single antenna users (see Fig. 8.1). The secrecy capacity region of the MISO broadcast channel (BC) for the case of perfect and instantaneous CSI at all terminals (transmitter and the receivers) has been characterized in [24, 25]. Using these results, it follows that for the two-user MISO BCCM, the sum s.d.o.f. is 2 with perfect and instantaneous CSIT.
The occurrence of pesticidal pollution in the environment and the resistance in the mosquito species makes an urge for the safer and an effective pesticide. Permethrin, a poorly water-soluble pyrethroid pesticide, was formulated into a hydrodispersible nanopowder through rapid solvent evaporation of pesticide-loaded oil in water microemulsion. Stability studies confirmed that the nanopermethrin dispersion was stable in paddy field water for 5 days with the mean particle sizes of 175.3 ± 0.75 nm and zeta potential of −30.6 ± 0.62 mV. The instability rate of the nanopermethrin particles was greater in alkaline (pH 10) medium when compared with the neutral (pH 7) and acidic (pH 4) dispersion medium. The colloidal dispersion at 45°C was found to be less stable compared with the dispersions at 25 and 5°C. The 12- and 24-h lethal indices (LC50) for nanopermethrin were found to be 0.057 and 0.014 mg l−1, respectively. These results were corroborative with the severity of damages observed in the mosquito larvae manifested in epithelial cells and the evacuation of the midgut contents. Further, the results were substantiated by the decrease in cellular biomolecules and biomarker enzyme activity in nanopermethrin treated larvae when compared to bulk and control treatment.
Three cases of internal carotid artery aneurysm affecting the distal cervical segment were retrospectively reviewed.
Two patients underwent open surgical repair requiring petrous segment exposure for bypass of the affected segment using a Fisch type A lateral skull base approach. The third patient underwent endovascular stenting.
There were no cerebrovascular complications post-operatively. Both open repair patients experienced temporary lower cranial nerve palsies. One required facial nerve grafting. All patients had patent grafts at follow up. The stent graft patient had a small endoleak at six months.
Endovascular and open approaches both have advantages and disadvantages. Treatment needs to be tailored to the lesion and the patient. An open surgical approach is difficult but well established. Endovascular treatment of these lesions is a relatively recent technique, and new cases need to be continually reported with a view to attaining long-term data.
To report three cases illustrating that it is not unusual for a primary eyelid tumour to metastasise to the parotid gland and vice versa.
Two patients with malignant parotid tumours underwent radical parotidectomy and presented subsequently with eyelid lesions. Biopsy showed that both eyelid lesions were histologically similar to the primary parotid tumour. A third patient was noted to have ipsilateral upper eyelid and parotid gland tumours. Histology and immunocytochemistry were used to differentiate the primary tumour and the metastasis.
These cases illustrate that tumours involving eyelids and parotid glands can present simultaneously or sequentially, and either of these structures could be the focus of primary or metastatic tumour. The important message for oculoplastic and parotid surgeons is to routinely assess both the periocular and parotid area when patients present with a mass in either structure.
The study characterizes a collection of 67 neonatal septicaemic Escherichia coli isolates on the basis of phylogroup, serotype, virulence, antibiotic resistance and also the association of CTX-M-producing E. coli and the ST131 clone in a developing country. Phylogroups B2 and D were predominant (33% and 19%, respectively). The most prevalent virulence factors (VFs) were traT (69%) and iucC (68%) and most VFs were concentrated in the B2 isolates. High levels of resistance (⩾70%) to cefotaxime, ciprofloxacin and trimethoprim/sulfamethoxazole was recorded but meropenem remained the most active antimicrobial. Six (9%) of the study isolates belonged to the ST131 clone, five of which were from the same hospital, and were either indistinguishable or closely related by pulsed-field gel electrophoresis. Although the prevalence of CTX-M-15-producing isolates was high (81%), the ST131 clone was relatively infrequent (11%) in extended spectrum β-lactamase (ESBL)-producers. The ST131 clone was characterized by the presence of blaCTX-M-15, qnrS, aac(6′)-Ib-cr, IncF plasmids and virulence determinants such as iucC, papC, traT, usp, hlyA, iroNE.coli, cnf, and sat. We conclude that clonal spread of ST131 did not contribute directly to the high prevalence of CTX-M-15 in our settings.
Callosobruchus maculatus (F.) (Coleoptera: Bruchidae) is an important stored grain pest of Lathyrus sativus L. (Leguminosae), commonly known as khesari, in India, Bangladesh and Ethiopia. Volatiles were collected from four varieties, i.e., Bio L 212 Ratan, Nirmal B-1, WBK-14-7 and WBK-13-1 of uninfested khesari seeds, and subsequently identified and quantified by gas chromatography mass spectrometry and gas chromatography flame ionization detector analyses, respectively. A total of 23 volatiles were identified in the four varieties of khesari seeds. In Bio L 212 Ratan and WBK-13-1 seeds, nonanal was the most abundant followed by farnesyl acetone; whereas farnesyl acetone was predominant followed by nonanal in Nirmal B-1 and WBK-14-7 khesari seeds. The olfactory responses of female C. maculatus toward volatile blends from four varieties of khesari seeds, and individual synthetic compounds and their combinations were examined through Y-shaped glass tube olfactometer bioassays. Callosobruchus maculatus showed significant preference for the whole volatile blends from Bio L 212 Ratan seeds compared to whole volatile blends from other three varieties. The insect exhibited attraction to five individual synthetic compounds, 3-octanone, 3-octanol, linalool oxide, 1-octanol and nonanal. A synthetic blend of 448, 390, 1182, 659 and 8114 ng/20 μl methylene chloride of 3-octanone, 3-octanol, linalool oxide, 1-octanol and nonanal, respectively, was most attractive to C. maculatus, and this combination might be used for insect pest management program such as baited traps.
The mm-wave as well as avalanche noise properties of IMPATT diode at D-band are efficiently estimated, with different poly-types of silicon carbide (SiC) and GaN as base materials, using advanced computer simulation techniques developed by the authors. The breakdown voltage of 4H-SiC (180 V) is more than the same for 6H-SiC, ZB- and Wz-GaN-based diode of 170,158, and 160 V, respectively. Similarly, the efficiency (14.7%) is also high in the case of 4H-SiC as compared with 6H-SiC and GaN-based diode. The study indicates that 4H-SiC IMPATT diode is capable of generating high RF power of about 8.38 W as compared with GaN IMPATT diode due to high breakdown voltage and negative resistance for the same frequency of operation. It is also observed that Wz-GaN exhibits better noise behavior 7.4 × 10−16 V2 s than SiC (5.16 × 10−15 V2 s) for IMPATT operation at 140 GHz. A comparison between the power output and noise from both the device reveals that Wz-GaN would be a suitable base material for high-power application of IMPATT diode with moderate noise.
Al–2.5% Mg alloy exhibits the Portevin–Le Chatelier (PLC) effect at room temperature for a wide range of strain rates. Tensile test has been carried out on a flat Al–2.5% Mg alloy sample at a strain rate of 3.7×10−6 s−1. The strain rate was chosen so that the type C PLC band appears in the sample. X-ray diffraction profile has been recorded from the gauge length portion of the deformed sample to investigate the microstructure of the PLC band. Analysis revealed that the dislocation density is much higher within the band compared to the undeformed sample even at small strain. The PLC band in this alloy possesses an equal fraction of screw and edge dislocations.
While the cause of Parkinson's disease (PD) remains unknown, evidence suggests certain environmental factors, such as well water drinking, herbicides, pesticides exposure and neurotoxins, may trigger the chain of oxidative reactions culminating in the death of dopaminergic neurons in substantia nigra to cause Parkinsonism. To investigate the possible impact of environmental risk factors for idiopathic PD, a case-control study was performed in the Eastern India.
During the period from January 1st, 2006 and December 10th, 2009, 175 PD patients (140 men, 35 women) and 350 non-Parkinson age-sex matched controls were included in the study. Subjects were given a structured neurological examination and completed an administered questionnaire which elicited detailed information on demographic data, pesticides, herbicides family history, occupation, dietary and smoking habits.
The multivariate analysis revealed that family history of PD, pesticide exposure, exposure to toxins other than pesticides and herbicides, rural living and previous history of depression were associated with increased risk of PD, whereas, smoking appeared to be a protective factor. Well water drinking for at least five years, though a significant risk factor on univariate analysis (OR=4.5, 95% CI=2.1-9.9), could not be proved significant in multivariate analysis. Head trauma, vegetarian dietary habit, occupation involving physical exertion and exposure to domestic pets were not as significant risk factors.
Results of our study support the hypothesis of multifactorial etiology of PD with environmental factors acting on a genetically susceptible host.