Bin Li and Jieqiong Shen
Proc. Amer. Math. Soc. 148 (2020), 2565-2578.
Abstract, references and article information

Véronique Bazier-Matte and Pierre-Guy Plamondon
Proc. Amer. Math. Soc. 148 (2020), 2397-2409.
Abstract, references and article information

You don't need a backer to start a business. Here's how to start a business from scratch.

A total of 27 Hong Kong residents who left Morocco on a chartered flight arranged by the Chinese Embassy in the Kingdom of Morocco arrived in Guangzhou today.

Among them, 26 people subsequently took the coaches arranged by the Hong Kong Special Administrative Region Government to return to Hong Kong through the Shenzhen Bay Port and have arrived at AsiaWorld-Expo.

One Hong Kong resident chose to stay in Guangzhou for a 14-day isolation period for medical surveillance in accordance with the relevant requirements.

The Department of Justice (DoJ) is responsible for making prosecutorial decisions. At times, these decisions attract extensive discussions in the community. It becomes interesting when overseas media and politicians embark upon allegations or purported demands relating to Hong Kong’s prosecutorial decisions.

Article 63 of the Basic Law provides that the DoJ of the Hong Kong Special Administrative Region shall control criminal prosecutions, free from any interference. This prosecutorial independence ought to be a feature in any society that cherishes the rule of law, and therefore attempts made by jurisdictions requesting such decisions to be made one way or another or even to request that they be varied is a blatant defiance of rule of law.

The DoJ acts independently without political, improper or undue influence, including those from public opinions and certainly not from overseas politicians who made these requests possibly not based on evidence or law but on political motives.

In cases in which legal proceedings are ongoing, we will not comment and neither should others as it may bring about the undesirable effect of a trial by the public. Statements made requesting the DoJ to drop all the charges or uttered with a view to affecting the DoJ’s role in controlling criminal prosecutions are futile. It is plainly wrong to label our prosecutions as politicised. On the contrary, no one, be they tycoons or politicians, will be above the law or be treated differently simply because they have a certain status or are pursuing certain beliefs or goals.

When law enforcement agencies have completed their investigation, they would seek legal advice from the DoJ. Our prosecutors would carefully consider the investigation reports and relevant materials submitted. A prosecution would only be commenced if the prosecutor is satisfied that there is sufficient admissible evidence to support a reasonable prospect of conviction.

The well-established procedures of our criminal justice system include the independent investigations by law enforcement agencies, the independent prosecutorial decisions based on objective assessment of evidence, applicable laws and in accordance with the Prosecution Code, and finally open trials by our independent judiciary. If we are to accede or be seen to yield to unreasonable demands to drop charges irresponsibly, we would not only be unfair and unprofessional but would also act in violation of the spirit of the rule of law.

I have explained the DoJ’s prosecution procedure on various occasions and stressed that our prosecutors are expected to apply the highest of professional standards in handling all criminal cases impartially and without fear or favour. They must not be influenced by political consideration. Cases should not be handled any differently irrespective of one’s own political beliefs or opinions.

The Hong Kong Special Administrative Region Government always respects and protects human rights and freedoms. However, these rights are not absolute. As pointed out by the Chief Justice of the Court of Final Appeal at the Ceremonial Opening of the Legal Year 2020: “It is important to understand that the enjoyment of these rights has limits so as not to affect adversely to an unacceptable level the enjoyment by other members of their community of their rights and liberties.” There are clear limits in the law to the exercise of these rights. When law is broken, action will be taken in accordance with the criminal justice system.

The rule of law is a core value in Hong Kong. We have to stand united in upholding our independent criminal justice system especially when it is under attack by any unfair and unfounded allegation made with a view to discrediting or undermining it. Any attempt to do so would only be attractive to those unfamiliar with our independent legal and judicial systems. We are obliged to continue to explain and ensure that their absence of knowledge would not override facts. We will continue to disseminate proper and accurate information and help clear any misunderstandings in the local and overseas communities.

Secretary for Justice Teresa Cheng wrote this article and posted it on her blog on April 26.

(Ecole Polytechnique Fédérale de Lausanne) EPFL chemists have developed sponges to capture various target substances, like gold, mercury and lead, dissolved in solution. The sponges are actually porous crystals called metal organic frameworks, and now one exists for capturing toxic hexavalent chromium from water.

Actinobacillus pleuropneumoniae (App) is the etiological agent of acute porcine pneumonia and responsible for severe economic losses worldwide. The capsule polymer of App serotype 1 (App1) consists of [4)-GlcNAc-β(1,6)-Gal-α-1-(PO4-] repeating units that are O-acetylated at O-6 of the GlcNAc. It is a major virulence factor and was used in previous studies in the successful generation of an experimental glycoconjugate vaccine. However, the application of glycoconjugate vaccines in the animal health sector is limited, presumably because of the high costs associated with harvesting the polymer from pathogen culture. Consequently, here we exploited the capsule polymerase Cps1B of App1 as an in vitro synthesis tool and an alternative for capsule polymer provision. Cps1B consists of two catalytic domains, as well as a domain rich in tetratricopeptide repeats (TPRs). We compared the elongation mechanism of Cps1B with that of a ΔTPR truncation (Cps1B-ΔTPR). Interestingly, the product profiles displayed by Cps1B suggested processive elongation of the nascent polymer, whereas Cps1B-ΔTPR appeared to work in a more distributive manner. The dispersity of the synthesized products could be reduced by generating single-action transferases and immobilizing them on individual columns, separating the two catalytic activities. Furthermore, we identified the O-acetyltransferase Cps1D of App1 and used it to modify the polymers produced by Cps1B. Two-dimensional NMR analyses of the products revealed O-acetylation levels identical to those of polymer harvested from App1 culture supernatants. In conclusion, we have established a protocol for the pathogen-free in vitro synthesis of tailored, nature-identical App1 capsule polymers.

In cyanobacteria, metabolic pathways that use the nitrogen-rich amino acid arginine play a pivotal role in nitrogen storage and mobilization. The N-terminal domains of two recently identified bacterial enzymes: ArgZ from Synechocystis and AgrE from Anabaena, have been found to contain an arginine dihydrolase. This enzyme provides catabolic activity that converts arginine to ornithine, resulting in concomitant release of CO2 and ammonia. In Synechocystis, the ArgZ-mediated ornithine–ammonia cycle plays a central role in nitrogen storage and remobilization. The C-terminal domain of AgrE contains an ornithine cyclodeaminase responsible for the formation of proline from ornithine and ammonia production, indicating that AgrE is a bifunctional enzyme catalyzing two sequential reactions in arginine catabolism. Here, the crystal structures of AgrE in three different ligation states revealed that it has a tetrameric conformation, possesses a binding site for the arginine dihydrolase substrate l-arginine and product l-ornithine, and contains a binding site for the coenzyme NAD(H) required for ornithine cyclodeaminase activity. Structure–function analyses indicated that the structure and catalytic mechanism of arginine dihydrolase in AgrE are highly homologous with those of a known bacterial arginine hydrolase. We found that in addition to other active-site residues, Asn-71 is essential for AgrE's dihydrolase activity. Further analysis suggested the presence of a passage for substrate channeling between the two distinct AgrE active sites, which are situated ∼45 Å apart. These results provide structural and functional insights into the bifunctional arginine dihydrolase–ornithine cyclodeaminase enzyme AgrE required for arginine catabolism in Anabaena.

Prominins (proms) are transmembrane glycoproteins conserved throughout the animal kingdom. They are associated with plasma membrane protrusions, such as primary cilia, as well as extracellular vesicles derived thereof. Primary cilia host numerous signaling pathways affected in diseases known as ciliopathies. Human PROM1 (CD133) is detected in both somatic and cancer stem cells and is also expressed in terminally differentiated epithelial and photoreceptor cells. Genetic mutations in the PROM1 gene result in retinal degeneration by impairing the proper formation of the outer segment of photoreceptors, a modified cilium. Here, we investigated the impact of proms on two distinct examples of ciliogenesis. First, we demonstrate that the overexpression of a dominant-negative mutant variant of human PROM1 (i.e. mutation Y819F/Y828F) significantly decreases ciliary length in Madin–Darby canine kidney cells. These results contrast strongly to the previously observed enhancing effect of WT PROM1 on ciliary length. Mechanistically, the mutation impeded the interaction of PROM1 with ADP-ribosylation factor–like protein 13B, a key regulator of ciliary length. Second, we observed that in vivo knockdown of prom3 in zebrafish alters the number and length of monocilia in the Kupffer's vesicle, resulting in molecular and anatomical defects in the left-right asymmetry. These distinct loss-of-function approaches in two biological systems reveal that prom proteins are critical for the integrity and function of cilia. Our data provide new insights into ciliogenesis and might be of particular interest for investigations of the etiologies of ciliopathies.

Bacterial type VII secretion systems secrete a wide range of extracellular proteins that play important roles in bacterial viability and in interactions of pathogenic mycobacteria with their hosts. Mycobacterial type VII secretion systems consist of five subtypes, ESX-1–5, and have four substrate classes, namely, Esx, PE, PPE, and Esp proteins. At least some of these substrates are secreted as heterodimers. Each ESX system mediates the secretion of a specific set of Esx, PE, and PPE proteins, raising the question of how these substrates are recognized in a system-specific fashion. For the PE/PPE heterodimers, it has been shown that they interact with their cognate EspG chaperone and that this chaperone determines the designated secretion pathway. However, both structural and pulldown analyses have suggested that EspG cannot interact with the Esx proteins. Therefore, the determining factor for system specificity of the Esx proteins remains unknown. Here, we investigated the secretion specificity of the ESX-1 substrate pair EsxB_1/EsxA_1 in Mycobacterium marinum. Although this substrate pair was hardly secreted when homologously expressed, it was secreted when co-expressed together with the PE35/PPE68_1 pair, indicating that this pair could stimulate secretion of the EsxB_1/EsxA_1 pair. Surprisingly, co-expression of EsxB_1/EsxA_1 with a modified PE35/PPE68_1 version that carried the EspG5 chaperone-binding domain, previously shown to redirect this substrate pair to the ESX-5 system, also resulted in redirection and co-secretion of the Esx pair via ESX-5. Our results suggest a secretion model in which PE35/PPE68_1 determines the system-specific secretion of EsxB_1/EsxA_1.

(Florida Atlantic University) Despite PPE use, reports show that many health care workers contracted COVID-19. A novel training technique reinforces the importance of using proper procedures to put on and take off PPE when caring for patients during the pandemic. Researchers vividly demonstrate how aerosol-generating procedures can lead to exposure of the contagion with improper PPE use. The most common error made by the health care workers was contaminating the face or forearms during PPE removal.

(European Society for Medical Oncology) A study of 4,532 men in the Veneto region of Italy has found that those who were being treated for prostate cancer with androgen-deprivation therapies (ADT) were less likely to develop the coronavirus COVID-19 and, if they were infected, the disease was less severe. The study is published in Annals of Oncology.

(University of California - Irvine) Cyanobacteria living in rocks in Chile's Atacama Desert extract water from the minerals they colonize and, in doing so, change the phase of the material from gypsum to anhydrite. Researchers at the University of California, Irvine and Johns Hopkins University gained verification of this process through experiments, and the work points to possible strategies for humans to stay hydrated in harsh environments.

(University of Warwick) 21st century X-ray technology has allowed University of Warwick scientists to peer back through time at the production of the armour worn by the crew of Henry VIII's favoured warship, the Mary Rose.

(Max Planck Institute for the Science of Human History) Three 16th-century skeletons from a mass burial in Mexico City highlight the role of the transatlantic slave trade in introducing and disseminating new pathogens to the Americas. Researchers from the Max Planck Institute for the Science of Human History and Escuela Nacional de Antropología e Historia in Mexico analyzed skeletal features, genetic data and isotopes to explore the life history of three enslaved Africans and explore the wide-ranging impacts of massive forced migration.

(Texas A&M University) Spoiling foods, souring wine and worsening wounds have a common culprit -- a process called oxidation. Although the ill effects of these chemical reactions can be curtailed by antioxidants, creating a sturdy platform capable of providing prolonged antioxidant activity is an ongoing challenge.

(University of Adelaide) An international team of scientists led by the University of Adelaide's Davies Research Centre has shown that it is possible to disentangle the DNA sequences of the chromosomes inherited from the mother and the father, to create true diploid genomes from a single individual.

(Rutgers University) Algae in the oceans often steal genes from bacteria to gain beneficial attributes, such as the ability to tolerate stressful environments or break down carbohydrates for food, according to a Rutgers co-authored study.

(University of Washington) By comparing new measurements from NASA's ICESat-2 mission with the original ICESat mission, which operated from 2003 to 2009, scientists were able to measure precisely how the Greenland and Antarctic ice sheets have changed over 16 years.

(American Association for the Advancement of Science) Ice sheet losses from Greenland and Antarctica have outpaced snow accumulation and contributed approximately 14 millimeters to sea level rise over 16 years (2003 to 2019), a new analysis of data from NASA's laser-shooting satellites has revealed.

(Marine Biological Laboratory) Microbial life is bubbling up to the ocean floor along with fluids from deeply buried petroleum reservoirs, reports a team of scientists from the University of Calgary and the Marine Biological Laboratory, Woods Hole.

Russia's GRU military intelligence service appears to have got hold of many emails from Chancellor Angela Merkel's constituency office in a 2015 hack attack on Germany's parliament, Der Spiegel magazine reported on Friday, without citing its sources. A spokesman for the German government had no immediate comment. Der Spiegel said federal criminal police and the federal cyber agency had been able to partially reconstruct the attack and found that two email inboxes from Merkel's office had been targeted.

As part of the College's move to remote learning, 143 first-year students are taking a series of virtual field courses to investigate biodiversity.

Linda J. Piccinino
May 1, 2017; 30:95-100
From Research to Practice

Daren Anderson
Jan 1, 2007; 20:10-16
Feature Articles

Karen B. Hirschman
Aug 1, 2014; 27:192-195
From Research to Practice

Martha Mitchell Funnell
Oct 1, 2007; 20:221-226
Articles

Barbara J. Anderson
Jan 1, 2004; 17:
Articles

The Lady of Dancehall, D'Angel, says although her COVID-19 Relief Concert did not meet its US$200,000 target, she is overwhelmed by the support. The event, held via Instagram Live last Friday, saw performances from the likes of Beenie Man, G...

In an interview with THE STAR last August, up-and-coming artiste Bad Gyal Jade dubbed herself the 'female Kartel'. Drawing comparisons between her style and flow and that of the incarcerated deejay, Jade said the label was a fitting one. Though...

Antoniette Bryden has fond memories of her mother, Arlene Reid, 51, a healthcare worker originally from Yallahs, St Thomas, who died of COVID-19 in Brampton, Ontario, Canada, on April 27. Reid, a personal support worker (PSW) who worked part-time...

As the pandemic ebbed in China, alumni from the region raised more than $2.1 million to send crucial protective gear to New York healthcare workers.

David Cluet
Apr 1, 2020; 19:701-715
Technological Innovation and Resources

Eva Griesser
May 1, 2020; 19:839-851
Research

We take you through the steps to clear your old devices from Sophos Central, so you've got more time to focus on the devices that matter.

This study sought to determine brain nicotine kinetics from the use of increasingly popular electronic cigarettes (E-cigs). Methods: Brain uptake of nicotine following inhalation from E-cigs was directly assessed in 17 E-cig users (8 females), using ¹¹C-nicotine and positron emission tomography. The brain nicotine kinetics parameters from E-cigs were compared with those from smoking combustible cigarettes (C-cigs). Results: After inhalation of a single puff of E-cig vapor, brain nicotine concentration rose quickly (mean T1/2 27 sec) with a peak amplitude 25% higher in females than males, resembling previous observations with C-cigs. Nonetheless, brain nicotine accumulation from E-cigs was smaller than that from C-cigs in both males and females (24% and 32%, respectively). Conclusion: E-cigs can deliver nicotine rapidly to the brain. Therefore, to the extent that rapid brain uptake promotes smoking reward, e-cigarettes might maintain a degree of nicotine dependence and also serve as non-combustible substitutes for cigarettes.

Background: ⁶⁸Ga PSMA PET CT (PSMA) is increasingly used in men with biochemical recurrence (BCR) post radical prostatectomy (RP), but its longer term prognostic / predictive potential in these men is unknown. The aim of this study was to evaluate the predictive value of PSMA PET for 3 year freedom from progression (FFP) in men with BCR post RP undergoing salvage radiotherapy (sRT). Methods: This prospective multi-center study enrolled 260 men between 2015 and 2017. Eligible patients were referred for PSMA with rising PSA following RP. Management following PSMA was recorded but not mandated. PSMA protocols were standardised across sites and reported prospectively. Clinical, pathological and surgical information, sRT, timing and duration of androgen deprivation (ADT), 3 year PSA results and clinical events were documented. FFP was defined as a PSA rise ≤ 0.2ng/mL above nadir post sRT, with no additional treatment. Results: The median PSA was 0.26ng/mL (IQR 0.15 - 0.59) and follow-up 38 months (IQR 31-43). PSMA was negative in 34.6% (90/260), confined to prostate fossa 21.5% (56/260), pelvic nodes 26.2% (68/260), and distant disease 17.7% (46/260). 71.5% (186/260) received sRT, 38.2% (71/186) to the fossa only, 49.4% (92/186) fossa + pelvic nodes and 12.4% (23/186) nodes alone/SBRT. PSMA was highly predictive of FFP at 3 years following sRT. Overall, FFP was achieved in 64.5% (120/186) of those who received sRT, 81% (81/100) with negative/fossa confined vs. 45% (39/86) for extra fossa disease (p<0.0001). On logistic regression PSMA was more independently predictive of FFP than established clinical predictors, including PSA, T-stage, surgical margin status or Gleason score (P < 0.002). 32% of men with a negative PSMA PET did not receive treatment. Of these, 66% (19/29) progressed, with a mean rise in PSA of 1.59ng/mL over the 3 years. Conclusion: PSMA PET result is highly predictive of FFP at 3 years in men undergoing sRT for BCR following RP. In particular, men with negative PSMA PET or disease identified as still confined to the prostate fossa demonstrate high FFP, despite receiving less extensive radiotherapy and lower rates of additional ADT than those with extra fossa disease.

Purpose: To investigate differences between positron emission tomography/magnetic resonance imaging (PET/MRI) and PET/computed tomography (PET/CT) in lesion detection and classification in oncological whole-body examinations and to investigate radiation exposure differences between both modalities. Material and Methods: In this prospective, single-center, observational study 1003 oncological examinations (918 patients, mean age 57.8±14.4y) were included. Patients underwent PET/CT and subsequent PET/MRI (149.8±49.7min after tracer administration). Examinations were reviewed by radiologists and nuclear medicine physicians in consensus. Additional findings, characterization of indetermiante findings in PETCT, missed findings in PET/MRI including their clinical relevance and effective dose of both modalities were investigated. McNemar’s test was used to compare lesion detection between both hybrid imaging modalities (p<0.001 indicating statistical significance). Results: Additional information in PET/MRI was reported in 26.3% (264/1003) of examinations compared to PET/CT (p<0.001). Of these, additional malignant findings were detected in 5.3% (53/1003), leading to a change in TNM-staging in 2.9% (29/1003) due to PET/MRI. Definite lesion classification of indeterminate PET/CT findings was possible in 11.1% (111/1003) with PET/MRI. In 2.9% (29/1003), lesions detected in PET/CT were not visible in PET/MRI. Malignant lesions were missed in 1.2% (12/1003) by PET/MRI leading to a change in TNM-staging in 0.5% (5/1003). The estimated mean effective-dose for whole-body PET/CT amounted to 17.6±8.7mSv in comparison to 3.6±1.4mSv in PET/MRI, resulting in a potential dose reduction of 79.6% (p<0.001). Conclusion: PET/MRI improves lesion detection and potentially reduces additional examinations in tumor staging. Especially younger patients may benefit from the clinically relevant dose reduction of PET/MRI compared to PET/CT.

10 October 2019

This briefing note is the result of a collaborative research process with the Zimbabwean private sector, government representatives, industry organizations and experts, drawing on best practice and senior-level insights to identify policy options for long-term economic revival and expansion in Zimbabwe, and pathways for inclusive development.