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Peatland ecosystems cover only 3% of the world’s land area; however, they store one-third of the global soil carbon (C). Microbial communities are the main drivers of C decomposition in peatlands, yet we have limited knowledge of their structure and function. While the microbial communities in the Northern Hemisphere peatlands are well documented, we have limited understanding of microbial community composition and function in the Southern Hemisphere peatlands, especially in Australia. We investigated the vertical stratification of prokaryote and fungal communities from Wellington Plains peatland in the Australian Alps. Within the peatland complex, bog peat was sampled from the intact peatland and dried peat from the degraded peatland along a vertical soil depth gradient (i.e., acrotelm, mesotelm, and catotelm). We analyzed the prokaryote and fungal community structure, predicted functional profiles of prokaryotes using PICRUSt, and assigned soil fungal guilds using FUNGuild. We found that the structure and function of prokaryotes were vertically stratified in the intact bog. Soil carbon, manganese, nitrogen, lead, and sodium content best explained the prokaryote composition. Prokaryote richness was significantly higher in the intact bog acrotelm compared to degraded bog acrotelm. Fungal composition remained similar across the soil depth gradient; however, there was a considerable increase in saprotroph abundance and decrease in endophyte abundance along the vertical soil depth gradient. The abundance of saprotrophs and plant pathogens was two-fold higher in the degraded bog acrotelm. Soil manganese and nitrogen content, electrical conductivity, and water table level (cm) best explained the fungal composition. Our results demonstrate that both fungal and prokaryote communities are shaped by soil abiotic factors and that peatland degradation reduces microbial richness and alters microbial functions. Thus, current and future changes to the environmental conditions in these peatlands may lead to altered microbial community structures and associated functions which may have implications for broader ecosystem function changes in peatlands.

Peatland ecosystems cover only 3 % of the world’s land area, however they store one-third of the global soil carbon (C). Peatlands play a central role in global C cycling as they contain more organic C than any other terrestrial ecosystem. Microbial communities are the main drivers of C decomposition in peatlands, yet we have limited knowledge of their structure and function. We investigated the vertical stratification of prokaryote and fungal communities from Wellington Plains peatland in the Australian Alps. Within the peatland complex, bog peat was sampled from the intact peatland and dried peat from the degraded peatland along a vertical soil depth gradient (i.e., acrotelm, mesotelm and catotelm). We analysed the prokaryote and fungal community structure, predicted functional profiles of prokaryotes using PICRUSt and assigned soil fungal guilds using FUNGuild. We found that the structure and the function of prokaryotes was vertically stratified in the intact bog. Carbon, manganese, nitrogen, lead and sodium best explained the prokaryote composition. Prokaryote richness was significantly higher in the intact bog acrotelm compared to degraded bog acrotelm. Fungal composition remained similar across the soil depth gradient, however there was a considerable increase in saprotroph abundance and decrease in endophyte abundance along the vertical soil depth gradient. The abundance of saprotrophs and plant pathogens was two-fold higher in the degraded bog acrotelm. Manganese, nitrogen, electrical conductivity and water table level (cm) best explained the fungal composition. Our results demonstrate that both fungal and prokaryote communities are shaped by soil abiotic factors and peatland degradation reduces microbial richness and alters microbial functions. Thus, current and future changes to the environmental conditions in these peatlands may lead to altered microbial community structure and associated functions which may have implications for broader ecosystem function changes in peatlands.

Parks and recreational spaces are places that are critical elements of the built and natural environment known to support health and wellbeing. ParkSeek is a Canadian initiative that aims to collect and disseminate information about the population health impacts of parks, recreational facilities, and protected areas. This infographic gives an overview of the findings of a literature search examining the impacts of environmental health and equity on park access in urban settings.

Supplemental material, sj-pdf-1-map-10.1177_23992026211005642 for Evaluation of pharmacists’ awareness of illegal online pharmacies and perceived impact on safe access to medicines by John B Hertig, Shannon M James, Connor J Hummel and Matthew J Rubin in Medicine Access @ Point of Care

The precipitation of calcium carbonate (CaCO3) from saturated solutions prepared using calcium chloride and sodium hydrogen carbonate under the influence of ultrasound (20 kHz, intensity ranging from 1.5−18.5 W cm−2) has been studied. For short reaction times or treatment at low intensity, precipitates containing up to 90% vaterite were recovered; longer (>30 min) times or higher intensities yielded up to 100% calcite. Changes in the crystal sizes were noted. The results are consistent with the literature model of CaCO3 crystallization by the initial formation of vaterite followed by a dissolution−recrystallization process. Although a complete explanation cannot be offered, the results help to explain some of the apparently conflicting information previously published on this topic.

Since October 2001, improvised explosive devices (IEDs) have been responsible for many of the combat deaths in Iraq and Afghanistan. While the United States and its coalition partners have recovered well from the initial surprise of the IED threat, the fact is that our country was caught off guard by the extent and sophistication of this weapon on the battlefield. We should not have been. The United State's approach to its science and technology (S&T) program is in need of reevaluation and change so that our country will be better prepared for future warfare. Terrorist groups and rogue nations will continue to conduct sophisticated attacks simply by leveraging commercial technologies. This article describes the essential changes needed to S&T. The views expressed in this article are those of the authors and are not necessarily the official policy of the US Navy or any other organization. The intent of this article is to foster dialogue and the changes needed to continuously stay ahead of our adversaries.

In October 1979, Albright wrote an editorial warning of the risks of cardiac toxicity due to bupivacaine and etidocaine. The editorial followed a report by Prentiss concerning a cardiac arrest in a patient receiving caudal anesthesia with etidocaine. In that case, cardiovascular collapse followed the rapid onset of convulsions after possible intravascular (iv) injection of etidocaine. To Albright’s knowledge, this was the sixth anecdotal case of sudden cardiovascular collapse following presumed iv injection of bupivacaine (0.5% or 0.75%) or etidocaine. He suggested that inadvertent iv administration of clinical doses of etidocaine and bupivacaine, in comparison with other local anesthetics (LAs), could result in almost simultaneous central nervous system and cardiovascular system toxicity without preceding hypoxia. Albright also noted that resuscitation was difficult, prolonged, and, in most situations, the outcome was poor. Subsequently, many additional cases of cardiovascular collapse were reported to the Federal Drug Administration (FDA) in the United States. A worrying number of these cases occurred in young previously healthy women who received epidural analgesia/anesthesia for childbirth. Albright’s editorial and the reports to the FDA prompted a letter to anesthesiologists in 1984 stating that 0.75% bupivacaine was no longer recommended for obstetric anesthesia because of the risk of cardiac arrest. Following this letter, the manufacturers of bupivacaine sent similar correspondence to Canadian anesthesiologists that caused considerable controversy and debate. In other countries, caution was urged in using 0.75% bupivacaine, although many anesthesiologists felt that the problem of cardiotoxicity was confined to the United States. In this issue of the Journal, Dillane and Finucane review the systemic toxicity of LAs, describing the mechanisms underlying central nervous system and cardiovascular toxicity associated with elevated plasma levels of LAs. They point out that systemic toxicity of LAs frequently results from inadvertent iv injection or from rapid absorption of the LA from the injection site with subsequent high plasma levels, and they suggest that there are benefits from the use of ultrasound during the performance of regional anesthesia. Ultrasound not only facilitates the identification of anatomical structures, hence avoiding iv injection, but also, it can facilitate more targeted administration of smaller volumes of LAs, thereby increasing the safety of regional anesthesia. What can we learn from this review article and other similar articles? First, the authors reiterate the history and the known facts regarding this potentially fatal complication. Second, by so doing, they encourage practicing anesthesiologists to examine their own practices and to consider whether LA administration is safe in light of the evidence presented. Although Albright and others implicated bupivacaine’s greater toxicity as the direct cause of cardiac arrest, this assessment was not universally accepted. As most drugs that are used for anesthesia are toxic if used in the wrong dose or wrong space, some anesthesiologists urged caution in blaming bupivacaine. These anesthesiologists questioned the anesthetic technique, as several of the obstetric cases presented to the FDA did not reflect what was considered good anesthetic practice at the time. In some of these cases, a large volume of a high concentration of LA was injected through the epidural J. Shannon, FCARCSI J. Douglas, MD (&) Department of Anesthesia, British Columbia’s Women’s Hospital and Health Centre and University of British Columbia, Room 1Q72, 4500 Oak Street, Vancouver, BC V6H 3N1, Canada e-mail: jdouglas@cw.bc.ca

The speech signal is used for transmission of linguistic information. High energy portions of the speech spectrum have higher signal-to-noise ratios than the low energy portions. As a result, these regions are more robust to noise. Since the speech signal is known to be very robust to noise, it is expected that the high energy regions of the speech spectrum carry the majority of the linguistic information. This letter tries to derive a frequency warping function directly from the speech signal by sampling the frequency axis nonuniformly with the high energy regions sampled more densely than the low energy regions. To achieve this, an ensemble average short-time power spectrum is computed from a large speech corpus. The speech-signal-based frequency warping is obtained by considering equal area portions of the log spectrum. The proposed frequency warping is shown to be similar to the frequency scales obtained through psycho-acoustic experiments, namely the mel and bark scales. The warping is then used in filterbank design for automatic speech recognition experiments. The results of these experiments show that cepstral features based on the proposed warping achieve performance under clean conditions comparable to that of mel-frequency cepstral coefficients, while outperforming them under noisy conditions.

In this paper, a feature extraction method that is robust to additive background noise is proposed for automatic speech recognition. Since the background noise corrupts the autocorrelation coefficients of the speech signal mostly at the lower-time lags, while the higher-lag autocorrelation coefficients are least affected, this method discards the lower-lag autocorrelation coefficients and uses only the higher-lag autocorrelation coefficients for spectral estimation. The magnitude spectrum of the windowed higher-lag autocorrelation sequence is used here as an estimate of the power spectrum of the speech signal. This power spectral estimate is processed further (like the well-known Mel frequency cepstral coefficient (MFCC) procedure) by the Mel filter bank, log operation and the discrete cosine transform to get the cepstral coefficients. These cepstral coefficients are referred to as the autocorrelation Mel frequency cepstral coefficients (AMFCCs). We evaluate the speech recognition performance of the AMFCC features on the Aurora and the resource management databases and show that they perform as well as the MFCC features for clean speech and their recognition performance is better than the MFCC features for noisy speech. Finally, we show that the AMFCC features perform better than the features derived from the robust linear prediction-based methods for noisy speech.

In 1979, the Sandinista National Liberation Front (FSLN) led the Nicaraguan revolution against the Somoza dictatorship. The FSLN as the ruling party began institutionalizing the revolution and consolidating its rule, immediately contending with political groups within and outside of Nicaragua, including the domestic business class, the Catholic Church, and the U.S. government. The Sandinistas faced the task of legitimating their power amid economic and political struggle. This thesis, analyzing the works of FSLN founder Carlos Fonseca, materials used in Sandinista education reform projects, and speeches, writings, and statements by Sandinista leaders in the 1980s, explores the FSLN's construction of an official historical narrative of resistance to exploitation through martyrdom and sacrifice. The party inserted the Sandinista revolution into this nationalist narrative, claiming moral superiority, authenticity, and legitimate representation of the Nicaraguan people. The martyrdom discourse incorporated the experiences of Nicaraguans under Somocista repression, contributing to the creation of official memory.

The aim of this study was to determine the prognostic significance of alterations in serum magnesium in patients with moderate to severe congestive heart failure.Reductions in serum magnesium have been postulated to play a role in promoting arrhythmias and to have an adverse impact on survival in congestive heart failure, although support for this postulate is lacking.Serum magnesium levels were measured in 1,068 patients enrolled in a survival study of class III or IV heart failure at the time of double-blind randomization to milrinone, a phosphodiesterase inhibitor, or placebo. All patients received conventional therapy with digoxin, diuretic drugs and a converting enzyme inhibitor throughout the trial. The median follow-up period was 6.1 months (range 1 day to 20 months).Patients with high serum magnesium (defined asor = 1.9 mEq/liter, n = 242) were less likely to survive than were patients with a normal magnesium level (n = 627) (p0.05, risk ratio = 1.41). Patients with a low magnesium level (defined asor = 1.5 mEq/liter, n = 199) had no difference in survival compared with the group with a normal magnesium level (p = NS, risk ratio = 0.89). At baseline, the patients in the high magnesium group were older and had more severe functional and renal impairment. An analysis after adjustment for these variables demonstrated no difference in survival comparing the low, normal and high magnesium groups. Although the three groups had no difference in frequency of ventricular tachycardia, length of longest run or frequency of ventricular premature beats on baseline Holter monitoring, the group with hypomagnesemia had more frequent ventricular couplets.Serum magnesium does not appear to be an independent risk factor for either sudden death or death due to all causes in patients with moderate to severe heart failure. Hypomagnesemia is associated with an increase in the frequency of certain forms of ventricular ectopic activity, but this is not associated with an increase in clinical events. The higher mortality rate among the patients with hypermagnesemia is attributable to older age, more advanced heart failure and renal insufficiency.

When designing noise robust speech recognition feature extraction algorithms, it is common to assume that the noise and speech signal are uncorrelated. This assumption allows the cross correlation terms to be ignored in the equations that describe the operation of these algorithms, thus making the mathematics more tractable. In this paper, we investigate the validity of this assumption in the context of the autocorrelation mel frequency cepstral coefficient (AMFCC) feature extraction algorithm. To carry out the investigation, we designed a modified AMFCC algorithm that forces the cross terms in the noisy signal autocorrelation equation to be zero. We then compared the performance of the modified algorithm to the un-modified algorithm in recognition experiments performed using the AURORA II database. From these evaluations, we show that the assumption is fair in 5 out of six tested noise cases. The difference in recognition accuracy between the AMFCC and modified AMFCC for these five noises was less than 5%.

It is generally believed that the lower-lag autocorrelation coefficients carry information about the spectral envelope and the higher-lag autocorrelation coefficients are more related to pitch information. In this paper, we use lower-lag and higher-lag ranges of the autocorrelation function separately for deriving speech recognition features, and investigate their role in terms of speech recognition performance. The state-of-the-art MFCC (mel frequency cepstral coefficient) features use the whole autocorrelation function in their computation and are used here as a benchmark in our experiments. Our recognition results from the Aurora II corpus show that the higher-lag autocorrelation coefficients perform as well as the whole autocorrelation function for clean speech, and provide better performance for noisy speech, while lower-lag autocorrelation coefficients are not as effective in this aspect.

Typical speech enhancement algorithms that operate in the Fourier domain only modify the magnitude component. It is commonly understood that the phase component is perceptually unimportant, and thus, it is passed directly to the output. In recent intelligibility experiments, it has been reported that the Short-Time Fourier Transform (STFT) phase spectrum can provide significant intelligibility when estimated using a window function lower in dynamic range than the typical Hamming window. Motivated by this, we investigate the role of the window function for STFT phase estimation in relation to speech enhancement. Using a modified STFT Analysis-Modification-Synthesis (AMS) framework, we show that noise reduction can be achieved by modifying the window function used to estimate the STFT phase spectra. We demonstrate this through spectrogram plots and results from two objective speech quality measures.

We launched our system in May 2013 to provide researchers with access to patient level data from our studies in the belief that greater access to these data would facilitate further research to advance medical science and lead to improvements in patient care. I am sorry that Jureidini and his team have had difficulty working within the system.1 We worked hard to …

Passive millimeter wave (PMMW) sensors have been proposed as forward vision sensors for enhanced vision systems used in low visibility aircraft landing. This work reports on progress achieved to date in the development and manufacturing of a demonstration PMMW camera. The unit is designed to be ground and flight tested starting 1996. The camera displays on a head-up or head-down display unit a real time true image of the forward scene. With appropriate head-up symbology and accurate navigation guidance provided by global positioning satellite receivers on-board the aircraft, pilots can autonomously (without ground assist) execute category 3 low visibility take-offs and landings on non-equipped runways. We shall discuss utility of fielding these systems to airlines and other users.