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The Antarctic Peninsula has experienced considerable anthropogenic warming in recent decades. While cryospheric responses are well defined, the responses of moss-dominated terrestrial ecosystems have not been quantified. Analysis of Landsat archives (1986–2021) using a Google Earth Engine cloud-processing workflow suggest widespread greening across the Antarctic Peninsula. The area of likely vegetation cover increased from 0.863 km2in 1986 to 11.947 km2in 2021, with an accelerated rate of change in recent years (2016–2021: 0.424 km2yr−1) relative to the study period (1986–2021: 0.317 km2yr−1). This trend echoes a wider pattern of greening in cold-climate ecosystems in response to recent warming, suggesting future widespread changes in the Antarctic Peninsula’s terrestrial ecosystems and their long-term functioning.

Parastomal hernias are an inevitable consequence of ostomy formation and their repairs remain a challenge to many surgeons. With multiple systems of classification and a multitude of techniques for hernia repair ranging from suture to mesh repair, the literature remains sparse with regards to the optimal method of repair. The authors describe the most commonly adopted techniques, discuss preventative measures, and review the current literature in the context of perioperative outcomes and hernia recurrence.

Nonsteroidal anti-inflammatory drug (NSAID) use has been investigated as a modifiable risk factor for postoperative pancreatic fistula (POPF) after pancreatoduodenectomy (PD). This study comprises a systematic review and meta-analysis examining the impact of perioperative NSAID use on rates of POPF after PD.

Primary ciliary dyskinesia (PCD), a disorder of the motile cilia, is now recognised as an underdiagnosed cause of bronchiectasis. Accurate PCD diagnosis comprises clinical assessment, analysis of cilia and the identification of biallelic variants in one of 50 known PCD-related genes, including HYDIN. HYDIN-related PCD is underdiagnosed due to the presence of a pseudogene, HYDIN2, with 98% sequence homology to HYDIN. This presents a significant challenge for Short-Read Next Generation Sequencing (SR-NGS) and analysis, and many diagnostic PCD gene panels do not include HYDIN. We have used a combined approach of SR-NGS with bioinformatic masking of HYDIN2, and state-of-the-art long-read Nanopore sequencing (LR_NGS), together with analysis of respiratory cilia including transmission electron microscopy and immunofluorescence to address the underdiagnosis of HYDINas a cause of PCD. Bioinformatic masking of HYDIN2after SR-NGS facilitated the detection of biallelic HYDINvariants in 15 of 437 families, but compromised the detection of copy number variants. Supplementing testing with LR-NGS detected HYDINdeletions in 2 families, where SR-NGS had detected a single heterozygous HYDINvariant. LR-NGS was also able to confirm true homozygosity in 2 families when parental testing was not possible. Utilising a combined genomic diagnostic approach, biallelic HYDINvariants were detected in 17 families from 242 genetically confirmed PCD cases, comprising 7% of our PCD cohort. This represents the largest reported HYDINcohort to date and highlights previous underdiagnosis of HYDIN-associated PCD. Moreover this provides further evidence for the utility of LR-NGS in diagnostic testing, particularly for regions of high genomic complexity.

Background Patients with unstable cervical spine (C-spine) fractures are at a significant risk of respiratory failure. There is no consensus on the optimal timing of tracheostomy in the setting of recent operative cervical fixation (OCF). This study evaluated the impact of tracheostomy timing on surgical site infections (SSIs) in patients undergoing OCF and tracheostomy.Methods Trauma Quality Improvement Program (TQIP) was used to identify patients with isolated cervical spine injuries who underwent OCF and tracheostomy between 2017 and 2019. Early tracheostomy (<7 days from OCF) was compared with delayed tracheostomy (≥7 days from OCF). Logistic regressions identified variables associated with SSI, morbidity, and mortality. Pearson correlations evaluated time to tracheostomy and length of stay (LOS).Results Of 1438 patients included, 20 had SSI (1.4%). There was no difference in SSI between early vs delayed tracheostomy (1.6% vs 1.2%, P= .5077). Delayed tracheostomy was associated with increased ICU LOS (23.0 vs 17.0 days, P< .0001), ventilator days (19.0 vs 15.0, P< .0001), and hospital LOS (29.0 vs 22.0 days, P< .0001). Increased ICU LOS was associated with SSI (OR 1.017; CI 0.999-1.032; P= .0273). Increased time to tracheostomy was associated with increased morbidity (OR 1.003; CI 1.002-1.004; P< .0001) on multivariable analysis. Time from OCF to tracheostomy correlated with ICU LOS (r (1354) = .35, P< .0001), ventilator days (r (1312) = .25, P< .0001), and hospital LOS (r (1355) = .25, P< .0001).Conclusion In this TQIP study, delayed tracheostomy after OCF was associated with longer ICU LOS and increased morbidity without increased SSI. This supports the TQIP best practice guidelines recommending that tracheostomy should not be delayed for concern of increased SSI risk.

This article describes a method for estimating the temperature of high-power piezoelectric actuators when a direct temperature measurement is impractical. The heat flow is estimated from the real component of the electrical power; then, the temperature is estimated by a transfer function that approximates the thermal response of the system. The transfer function can be derived analytically from a lumped-element approximation or calibrated experimentally by using a system identification method. The proposed method is demonstrated on a piezoelectric stack actuator used in a high-speed nanopositioning device. A second-order transfer function estimates the temperature to within 3 $^{\circ }$C of a reference measurement for a range of operating conditions. The proposed method is suitable for protecting piezoelectric actuators in applications where direct temperature measurement is impractical, for example, due to space or wiring constraints.

Background: Same day discharge (SDD) may be considered in some patients undergoing minimally invasive adrenalectomy (MIA). Recent studies have demonstrated similar outcomes between SDD and admitted patients; however, most excluded pheochromocytoma and adrenal metastases. This study evaluates 30-day complications and hospital readmission in a large cohort of patients undergoing MIA. Methods: Adult patients undergoing MIA (2010–2020) for benign adrenal disorders, pheochromocytoma, and adrenal metastases were identified within the ACS-NSQIP database. Comparisons between patients having SDD versus admission were performed. Factors associated with 30-day complications and unplanned readmission were evaluated by multivariable regression modeling. Results: Of 7316 patients who underwent MIA, 254 had SDD. Baseline characteristics were similar between groups, although SDD patients had lower ASA class (p&lt; 0.001) and were more likely to undergo MIA for nonfunctioning adenoma or primary aldosteronism (p= 0.001). After adjusting for covariates, higher ASA class and presence of medical comorbidities were associated with increased complications (p&lt; 0.001; p&lt; 0.05) and unplanned readmission (p&lt; 0.001; p&lt; 0.05). Additionally, prolonged operative time was associated with 30-day complications (p&lt; 0.001). Notably, SDD was not associated with increased complications (OR 0.78, 95% CI 0.38–1.61, p= 0.502) or unplanned readmission (OR 0.76, 95% CI 0.35–1.64, p= 0.490). The rate of SDD for MIA increased from 1.48% in 2017 to 10.81% in 2020. Conclusions: Not all patients undergoing MIA should have SDD; however, the current analysis demonstrates a trend toward SDD and supports its safety in select patients with adrenal metastases and benign adrenal disorders including pheochromocytoma.

Giant paraesophageal hernias contain greater than fifty percent of the stomach above the diaphragm. Over fifty percent of large bowel obstructions are due to colorectal adenocarcinoma. Here, we present a rare case of a 69-year-old female patient who developed a closed loop colonic obstruction caused by a colonic mass in the distal transverse colon within a giant paraesophageal hernia. We successfully performed emergent paraesophageal hernia reduction and mesh repair with extended right hemicolectomy and ileocolonic anastomosis. Emergent hernia repair via an abdominal approach can be used in this setting.

Schedule 6 to the UK Finance Act of 1989 amends the regulation of company pension trusts for employees who joined funds beginning June 1,1989. Under Schedule 6, employers are able to establish un-approved top-up schemes to provide benefits above Inland Revenue (IR) limits without tax approval. While IR requirements limit the maximum employee contribution to an approval scheme to 15% of earnings, the Act introduces a limit on earnings of 60,000 pounds sterling. The Act creates clear tax advantages for unfunded schemes since no tax is payable until the benefits come into payment, unlike a funded plan, in which employees pay taxes on employers' contributions to the scheme. For the payment of additional pension benefits, unfunded arrangements will prove more beneficial, while funded un-approved plans will be favored for making lump sum payments.

Sclerosing Angiomatoid Nodular Transformation (SANT) of the spleen, first reported as a distinct histopathological entity in 2004, is exceedingly rare in children. The clinical progression and pathophysiologic features of this disease are poorly described in the literature. We performed a literature review of reported cases of SANT. Out of 258 reported cases, only five were in children. We present a sixth case of SANT in a four-year-old boy who presented with chronic anemia and elevated inflammatory markers. The relative variability in case presentation and the clinical concern for malignancy, warrant further disease characterization and discussion of management.

We quantified glycogen in human endometrium and found that synthesis was regulated by insulin, not progesterone, through acute deactivation of GSK and increased glycogen synthase expression.

Laser scanning lithography is a maskless method for exposing films of photoresist during semiconductor manufacturing. In this method a focused beam is scanned over a surface with varying intensity to create features in the photoresist. Given the shape of a desired feature, an exposure pattern must be found that approximates this shape in the developed photoresist. This can be cast as an optimization problem, which is complicated by the non-negative nature of the exposure function and the non-linear photochemistry of the film. In this article, a nonlinear programming approach is described that results in a tractable optimization problem which accounts for all of the practical constraints encountered in laser scanning lithography. This method is demonstrated to create a sub-wavelength feature which is verified by optical finite element simulation with a resolution of 20 nm.

This article describes a method for tracking control of monolithic nanopositioning systems using integrated piezoelectric sensors. The monolithic nanopositioner is constructed from a single sheet of piezoelectric material where a set of flexures are used for actuation and guidance, and another set are used for position sensing. This arrangement is shown to be highly sensitive to in-plane motion (in the x- and y-axis) and insensitive to vertical motion, which is ideal for position tracking control. The foremost difficulty with piezoelectric sensors is their low-frequency high-pass response. In this article, a simple estimator circuit is used to allow the direct application of integral tracking control. Although the system operates in open-loop at DC, dynamic command signals such as scanning trajectories are accurately tracked. Experimental results show significant improvements in linearity and positioning error.

A new method for reducing harmonic distortion due to element mismatch in digital-to-analog converters is described. This is achieved by using a large high-frequency periodic dither. The reduction in nonlinearity is due to the smoothing effect this dither has on the nonlinearity, which is only dependent on the amplitude distribution function of the dither. Since the high-frequency dither is unwanted in the output of the digital-to-analog converter, the dither is removed by an output filter. The fundamental frequency component of the dither is attenuated by a passive notch filter and the remaining fundamental component and harmonic components are attenuated by the low-pass reconstruction filter. Two methods that further improve performance are also presented. By reproducing the dither on a second channel and subtracting it using a differential amplifier, additional dither attenuation is achieved; and by averaging several channels, the noise-floor of the output is improved. Experimental results demonstrate more than 10 dB improvement in the signal-to-noise-and-distortion ratio. [ABSTRACT FROM AUTHOR]

Endometrial cancer develops during exposure to estrogen unopposed by progesterone. Traditional formulations for menopausal hormone therapy include a progestin in women with a uterus. However, progestin exposure increases breast cancer risk in postmenopausal women. Alternatives to progestin include bazedoxifene (BZA), a selective estrogen receptor modulator, which prevents estrogen induced endometrial hyperplasia in clinical trials. Molecular mechanisms responsible for BZA's antiproliferative effect are not fully elucidated. We profiled endometrial adenocarcinoma, hyperplasia, and normal proliferative endometrium for differential expression in genes known to be regulated by estrogens or progesterone. Fibroblast growth factor (FGF)18, a paracrine growth factor promoting epithelial proliferation, was significantly increased in adenocarcinoma. Progesterone represses FGF18 by inducing heart and neural crest derivatives expressed transcript 2 (HAND2) in stromal cells. Notably, we confirmed lower HAND2 mRNA in adenocarcinoma, along with higher FGF tyrosine kinase receptor 2 and E74-like factor 5, collectively promoting FGF18 activity. We hypothesized BZA reduces epithelial proliferation by inhibiting FGF18 synthesis in stromal cells. To determine whether BZA regulates FGF18, we treated primary stromal cells with BZA or vehicle. In vitro, BZA reduced FGF18, but did not affect, HAND2. CD1 female mice received either BZA, conjugated estrogen (CE), or combined BZA/CE for 8 weeks. CE-treated mice had nearly 3-fold higher FGF18 expression. In contrast, BZA-treated mice, alone or with CE, had similar FGF18 as controls. Unexpectedly, BZA, alone or with CE, reduced HAND2 more than 80%, differing from progesterone regulation. Reduction of FGF18 is a potential mechanism by which BZA reduces endometrial proliferation and hyperplasia induced by estrogens. However, BZA works independently of HAND2, revealing a novel mechanism for progestin-free hormone therapy in postmenopausal women.

This paper presents a case study of BIM implementation for Design for Manufacture and Assembly (DfMA). The project is a Knowledge Transfer Partnership (KTP) between the University of Salford and Links FF&E, a design, manufacture and fit-out SME based in the UK. The project aims to implement BIM as a catalyst for a Lean transformation, streamlining process and operations. Initially, organisational process are reviewed, which is followed by implementing appropriate technologies to enable subsequent people and process transformation. The 30 month project is organized in 6 key stages. This paper presents findings from the first four stages that have been completed to date of 1. Establishing best practice knowledge in BIM; 2. Conducting a review and analysis of the organisation's current situation, 3. Developing a BIM-based collaborative strategy, and the fourth, which is currently progressing, 4. Pilot implementation of BIM collaborative strategy for DfMA. The remaining stages will conduct a project evaluation, before finally implementing an Enterprise Resource Planning (ERP) system.

Nanopositioning stages are an example of motion systems that are required to accurately perform high frequency repetitive scanning motions. The tracking performance can be significantly increased by iteratively updating a feedforward input by using a nonparametric inverse plant model. However, in this paper it is shown that current approaches lack systematic robustness considerations and are suffering from limited design freedom to enforce satisfying convergence behavior. Therefore, inspired by the existing Iterative Learning Control approach, robustness is added to the existing methods to enable the desired convergence behavior. This results in the Robust Iterative Inversion-based Control method, whose potential for superior convergence is experimentally verified on a Nanopositioning system.

This paper, written at the invitation of the editors of Landscapes, responds to the re-interpretation (published in this issue of Landscapes) following new field survey of the date of a linear earthwork which formed part of my thesis that an early English ‘kingdom’ can be identified in the upper Swaledale valley. The purpose of the response is not to challenge the new dating, but rather to place both it and the former chronology into local context – and perhaps more importantly to consider the landscape significance of Yorkshire's dykes in more general terms in the light of recent thinking by other scholars.

Integral Resonant Control (IRC) is a simple and robust control scheme for vibration damping. Combined with an integral tracking controller, the IRC has been shown to improve the performance of a wide range of nanopositioners. However, the overall improvement in positioning performance is limited by the pole induced by the IRC. Through selective zero placement, the induced pole can be placed near origin. A structured PI tracking controller, where the PI gains are selected to place a zero at a specific location, is used to cancel the pole. This effectively reduces the order of the system by one. For this system, controller gains are derived analytically in order to maximize tracking bandwidth. Simulation results for one axis of a nanopositioner are provided for both standard and modified IRC schemes. Compared to the standard IRC scheme, the modified IRC scheme is found to provide a 55% increase in the ±1 dBbandwidth and a reduction of both maximum and rms tracking errors.

In this paper, an improvement to Integral Force Feedback (IFF) damping control is proposed. The main limitation of Integral Force Feedback is that the maximum modal damping depends on the system's parameters. Hence, for some system achievable damping is insignificant. The proposed improvement allows any arbitrary damping ratio to be achieved for a system by introducing a new feed-through term in the system. To achieve displacement tracking, one technique is to enclose the system in an integral feedback loop. However, the bandwidth is limited due to the effects of an additional pole in the damping loop. The proposed Structured PI controller is parameterised so that it contains a zero that cancel the additional pole. Experiment was conducted on a commercial objective lens positioner. The results show an exceptional tracking and damping performance and the system's insensitivity to changes in resonance frequency. The maximum bandwidth achievable with a commercial PID controller is 26.1 Hz. In contrast, with the proposed method, the bandwidth is increased to 255 Hz.

ABSTRACTAt Walkhampton, west Devon, a continuous line of field boundaries apparently represents the remains of two sides and three corners of a roughly rectangular enclosure of c. 175 hectares. We argue on stratigraphic grounds that the Walkhampton Enclosure (WE) pre-dates the Norman Conquest. It was sited strategically — defended by watercourses to the west and south, and located where two important long-distance roads merged to cross the River Walkham. At its centre lies Welltown Farm (probably once Bickwell), whose earliest known form was a twelfth-century hall; it is set within a pear-shaped embanked enclosure. It is likely that the WE played a key role in West Saxon control of the area in the early ninth century, before the establishment of the burh at Lydford. Walkhampton was a royal manor at the time of the Domesday survey; we suggest that the old territory of Roborough hundred was ‘royalised’ by a West Saxon king, with its centre transferred to Walkhampton. The WE may be interpreted as a late Saxon inland, administratively a royal manor liable to render a contribution to the ‘farm of one night’, supporting a peripatetic royalty and other important officials.

This paper examines the performance of the pseudospectral optimal control scheme for closed-loop time-optimal attitude maneuvering of the NPSAT1 spacecraft, a magnetically actuated spacecraft designed and built at the Naval Postgraduate School. The closed-loop control is devised and implemented using the notion of Carathéodory-π solutions: repeated computation and update of the complete open-loop control solution in real-time. The performance of the pseudospectral feedback-control scheme is compared to a standard state feedback-control technique. It is shown that the use of standard state feedback control leads to significantly slower convergence time and may lead to substantially lower performance metrics. The substantial performance gains when using closed-loop optimal control are attributed to the optimal scheme’s ability to exploit the full maneuverability envelope of the spacecraft by applying bang-bang controls in all three directions. In contrast, traditional gain-based feedback control laws substantially limit the performance of the vehicle to well below its physical capabilities. The feasibility of each open-loop optimal control solution is verified by numerical propagation while Pontryagin’s necessary conditions for optimality are used to verify the solution’s optimality.

ABSTRACTAn east-west route across Dartmoor, marked by a series oflate medieval granite crosses, probably goes back at least to the eighth century; it is the moorland component of the pre-Conquest road from Ashburton (and Exeter) to Tavistock and then through Horsebridge and into central Cornwall. The road links up with, and partly follows, another road linking important early medieval places in west Devon, which may once have related to the ‘frontier’ with Cornwall. Such early roads originated as instruments of elite control and were critical engines of regional military and political stratagems. Understanding their courses, in conjunction with other evidence, may aid the reconstruction of pre- Conquest settlement and political geography.

This paper describes the design of a flexure‐guided, two‐axis nanopositioner (scanner) driven by piezoelectric stack actuators. The scanner is specifically designed for high‐speed scanning probe microscopy (SPM) applications, such as atomic force microscopy (AFM). A high‐speed AFM scanner is an essential component for acquiring high‐resolution, three‐dimensional, time‐lapse images of fast processes such as the rapid movement of cells and the diffusion of DNA molecules. A two‐axis SPM scanner is proposed, where the slow and fast scanning axes are serially connected and flexure guided to minimize runout. The scanner's achievable scan range is approximately 10µm × 10µm. Finite element analysis is utilized to optimize the mechanical resonance frequencies of the scanner. Experimental results show a first major resonance in the slow and fast axis at 1.5 and 29 kHz, respectively. This paper also discusses the various tradeoffs between speed, range, electrical requirements, and scan trajectory design for high‐speed nanopositioning. Copyright © 2009 John Wiley and Sons Asia Pte Ltd and Chinese Automatic Control Society