Editorial: The society for environmental geochemistry and health (SEGH): 50 years and beyond.

When the SEGH international board released a short editorial paper back in 2019, we described an aim to increase the membership offering, whilst improving the diversity of input regionally, by scientific discipline and to ensure greater and more regular contact across the regions from 2020 onwards. Wider aspirations described in 2019 (Watts et al. 2019) are discussed within this short communication at the end of 2021 to evaluate progress made. In particular, how the SEGH community adapted to the unprecedented circumstances that have challenged each and every one of us throughout the COVID-19 pandemic since early 2020 and are likely to influence our activities for the foreseeable future.

Dimensional Effects on the Charge Density Waves in Ultrathin Films of TiSe2.

Charge density wave (CDW) formation in solids is a critical phenomenon involving the collective reorganization of the electrons and atoms in the system into a wave structure, and it is expected to be sensitive to the geometric constraint of the system at the nanoscale. Here, we study the CDW transition in TiSe2, a quasi-two-dimensional layered material, to determine the effects of quantum confinement and changing dimensions in films ranging from a single layer to multilayers. Of key interest is the characteristic length scale for the transformation from a two-dimensional case to the three-dimensional limit. Angle-resolved photoemission spectroscopy (ARPES) measurements of films with thicknesses up to six layers reveal substantial variations in the energy structure of discrete quantum well states; however, the temperature-dependent band gap renormalization converges at just three layers. The results indicate a layer-dependent mixture of two transition temperatures and a very-short-range CDW interaction within a three-dimensional framework.

Impact of skeletal-related events on survival in patients with metastatic prostate cancer prescribed androgen deprivation therapy.

OBJECTIVE: To investigate the impact of skeletal-related events on survival in patients with metastatic prostate cancer prescribed long-term androgen deprivation therapy. METHODS: This historical cohort study was conducted in two hospitals in Hong Kong. Patients who were diagnosed with metastatic prostate cancer and prescribed androgen deprivation therapy between January 2006 and December 2011 were included. Details of skeletal-related events and mortality were examined. RESULTS: The median follow-up was 28 (range, 1-97) months. Of 119 patients, 52 (43.7%) developed skeletal-related events throughout the study, and the majority received bone irradiation for pain control. The median actuarial overall survival and cancer-specific survival for patients with skeletal-related events were significantly shorter than those without skeletal-related events (23 vs 48 months, P=0.003 and 26 vs 97 months, P<0.001, respectively). Multivariate analysis revealed that the adjusted hazard ratio of presence of skeletal-related events on overall and cancer-specific survival was 2.73 (95% confidence interval, 1.46-5.10; P=0.002) and 3.92 (95% confidence interval, 1.87-8.23; P<0.001), respectively. A prostate-specific antigen nadir of >4 ng/mL was an independent poor prognostic factor for overall and cancer-specific survival after development of skeletal-related events (hazard ratio=10.42; 95% confidence interval, 2.10-51.66 and hazard ratio=10.54; 95% confidence interval, 1.94-57.28, respectively). CONCLUSIONS: Skeletal-related events were common in men with metastatic prostate cancer. This is the first reported study to show that a skeletal-related event is an independent prognostic factor in overall and cancer-specific survival in patients with metastatic prostate cancer prescribed androgen deprivation therapy. A prostate-specific antigen nadir of >4 ng/mL is an independent poor prognostic factor for overall and cancer-specific survival following development of skeletal-related events.

Surface Collective Modes in the Topological Insulators Bi_{2}Se_{3} and Bi_{0.5}Sb_{1.5}Te_{3-x}Se_{x}.

We used low-energy, momentum-resolved inelastic electron scattering to study surface collective modes of the three-dimensional topological insulators Bi_{2}Se_{3} and Bi_{0.5}Sb_{1.5}Te_{3-x}Se_{x}. Our goal was to identify the "spin plasmon" predicted by Raghu and co-workers [Phys. Rev. Lett. 104, 116401 (2010)]. Instead, we found that the primary collective mode is a surface plasmon arising from the bulk, free carriers in these materials. This excitation dominates the spectral weight in the bosonic function of the surface χ^{"}(q,ω) at THz energy scales, and is the most likely origin of a quasiparticle dispersion kink observed in previous photoemission experiments. Our study suggests that the spin plasmon may mix with this other surface mode, calling for a more nuanced understanding of optical experiments in which the spin plasmon is reported to play a role.

Uptake Kinetics of Arsenic in Upland Rice Cultivar Zhonghan 221 Inoculated with Arbuscular Mycorrhizal Fungi.

Arbuscular mycorrhizal fungi (AMF) appear to be highly associated with arsenic (As) uptake in host plants because arsenate (As(V)) and phosphorus (P) share the same transporter, whereby AMF can enhance P uptake. A short-term experiment was conducted for low- (0 to 0.05 mM As) and high-affinity (0 to 2.5 mM As) uptake systems, to investigate the AMF role on As uptake mechanism in plants, which may explain As uptake kinetics in upland rice cultivar: Zhonghan 221. When concentration of As ranged from 0 to 0.05 mM, Funneliformis geosporum (Fg) significantly decreased arsenite (As(III)) and monomethylarsonicacid (MMA) uptake when (p < 0.05) compared to non-mycorrhizal (NM) treatment, since the major route for (As(III)) in rice roots-rice silicon transporter Lsi1 would be influenced by Fg inoculation at high As concentrations. Fg can also reduce As(V) uptake significantly (p < 0.05) under both uptake systems relative to NM treatment, whereas, Funneliformis mosseae (Fm) increased As(V) and MMA uptake in rice roots, with MMA uptake rate generally lower than As(III) and As(V). Using suitable AMF species inoculation with rice, As uptake and accumulation in rice grains can be reduced and the risk to human health, once consumed, can be minimized.

Depth of a strong jovian jet from a planetary-scale disturbance driven by storms.

The atmospheres of the gas giant planets (Jupiter and Saturn) contain jets that dominate the circulation at visible levels. The power source for these jets (solar radiation, internal heat, or both) and their vertical structure below the upper cloud are major open questions in the atmospheric circulation and meteorology of giant planets. Several observations and in situ measurements found intense winds at a depth of 24 bar, and have been interpreted as supporting an internal heat source. This issue remains controversial, in part because of effects from the local meteorology. Here we report observations and modelling of two plumes in Jupiter's atmosphere that erupted at the same latitude as the strongest jet (23 degrees N). The plumes reached a height of 30 km above the surrounding clouds, moved faster than any other feature (169 m s(-1)), and left in their wake a turbulent planetary-scale disturbance containing red aerosols. On the basis of dynamical modelling, we conclude that the data are consistent only with a wind that extends well below the level where solar radiation is deposited.

Bioaccumulation of heavy metals in fish and Ardeid at Pearl River Estuary, China.

Sediment, fish (tilapia, Oreochromis mossambicus and snakehead, Channa asiatica), eggs and eggshells of Little Egrets (Egretta garzetta) and Chinese Pond Herons (Ardeola bacchus) were collected from Mai Po Ramsar site of Hong Kong, as well as from wetlands in the Gu Cheng County, Shang Hu County and Dafeng Milu National Nature Reserve of Jiangsu Province, China between 2004 and 2007 (n=3-9). Concentrations of six heavy metals were analyzed, based on inductively coupled plasma optical emission spectrometry (ICP-OES). Significant bioaccumulations of Cd (BAF: 165-1271 percent) were observed in the muscle and viscera of large tilapia and snakehead, suggesting potential health risks to the two bird species, as the fishes are the main preys of waterbirds. Significant (p<0.01) linear relationships were obtained between concentrations of Cd, Cr, Cu, Mn, Pb and Zn in the eggs and eggshells of various Ardeid species, and these regression models were used to extrapolate the heavy metal concentrations in the Ardeid eggs of Mai Po. Extrapolated concentrations are consistent with data in the available literature, and advocate the potential use of these models as a non-invasive sampling method for predicting heavy metal contamination in Ardeid eggs.

How can the R.E.N.A.L. nephrometry scoring system aid management of a solid renal mass?

OBJECTIVES. To investigate use of the R.E.N.A.L. nephrometry score in relation to the choice of treatment and postoperative complications for renal masses. DESIGN. Case series. SETTING. A tertiary referral hospital in Hong Kong. PATIENTS. Data of patients undergoing nephrectomy were collected retrospectively from a clinical database and analysed. A R.E.N.A.L. nephrometry score was allocated to each renal tumour by a blinded qualified radiologist, utilising computerised imaging systems. Patient demographics, choice of surgery (radical vs partial), and approaches (open vs minimally invasive) were analysed with respect to their R.E.N.A.L. score. RESULTS. In all, 74 patients were included during the study period, of which 38 underwent partial nephrectomy and 36 underwent radical nephrectomy. No differences between the groups were found with respect to patient demographics. There were significant differences between the partial and radical nephrectomy groups in terms of their mean nephrometry score (6.9 vs 9.3, P<0.001). The mean nephrometry sum was also significantly different in the open approach versus the minimally invasive approach in patients having partial nephrectomy (7.8 vs 6.0, P=0.001). There was no difference in the postoperative 90-day morbidity and mortality in the partial nephrectomy and radical nephrectomy groups. CONCLUSIONS. The R.E.N.A.L. nephrometry score of a renal mass correlated significantly with our choice of surgery (partial vs radical) and our approach to surgery (open vs minimally invasive surgery), particularly in the partial nephrectomy group. It does not, however, correlate with postoperative complications. The nephrometry score provides a useful tool for objectively describing renal mass characteristics and enhancing better communication for the operative planning directed at renal masses.

Unraveling the adipocyte inflammomodulatory pathways activated by North American ginseng.

BACKGROUND: North American (NA) ginseng (Panax quinquefolius) is a popular natural health product (NHP) that has been demonstrated to regulate immune function, inflammatory processes and response to stress and fatigue. Recent evidence suggests that various extracts of NA ginseng may have different bioactivities because of distinct profiles of ginsenosides and polysaccharides. To date, the bioactive role of ginseng on adipocytes remains relatively unexplored. OBJECTIVE: The goal of this work was to study the extract-specific bioactivity of NA ginseng on differentiated preadipocyte gene expression and adipocytokine secretion. METHODS: In vitro differentiated 3T3-L1 preadipocytes were treated with 25 and 50 µg ml of either crude ethanol (EtOH) or aqueous (AQ) NA ginseng extracts, or polysaccharide and ginsenoside extracts isolated from the AQ extract. Global gene expression was studied with microarrays and the resulting data were analyzed with functional pathway analysis. Adipocytokine secretion was also measured in media. RESULTS: Pathway analysis indicated that the AQ extract, and in particular the polysaccharide extract, triggered a global inflammomodulatory response in differentiated preadipocytes. Specifically, the expression of Il-6 (interleukin 6), Ccl5 (chemokine (C-C motif) ligand 5), Nfκb (nuclear factor-kappaB) and Tnfα (tumor necrosis factor alpha) was increased. These effects were also reflected at the protein level through the increased secretion of IL-6 and CCL5. No effect was seen with the EtOH extract or ginsenoside extract. Using a specific toll-like receptor 4 (TLR4) inhibitor reduced the upregulation of inflammatory gene expression, indicating the relevance of this pathway for the signaling capacity of NA ginseng polysaccharides. CONCLUSION: This work emphasizes the distinct bioactivities of different ginseng extracts on differentiated preadipocyte signaling pathways, and highlights the importance of TLR4 for mediating the inflammomodulatory role of ginseng polysaccharides.

Metastatic carcinoma of breast in the urinary bladder.

Less than 5% of breast cancers present as metastasis, and urinary bladder secondaries were only sporadically reported in the literature. However, they may even be responsible for the initial presentation, for which reason they can pose a diagnostic challenge. We present here what we believe is the first such case in Hong Kong, with a review of this entity.

Delayed oseltamivir treatment is associated with longer viral shedding of pandemic (H1N1) 2009 virus.

During the early phase of the influenza pandemic in 2009, all cases of laboratory-confirmed pandemic (H1N1) 2009 (pH1N1) infection required compulsory isolation in hospital. These cases were offered oseltamivir treatment and only allowed to be discharged from the hospital when three consecutive respiratory specimens were negative for the virus by reverse transcription-polymerase chain reaction (RT-PCR). We reviewed the case records of these patients to assess the viral shedding kinetics of the pH1N1 virus. We defined viral shedding duration as the interval from illness onset date to the date of collection of the last positive specimen from the patients. Fifty-six patients were included in the study, of whom 96% received oseltamivir. The median viral shedding duration of pH1N1 virus by viral culture and RT-PCR were 3 days and 4 days, respectively. Patients who started oseltamivir treatment >48 h after onset had a significantly longer median viral shedding duration by viral culture than those who started treatment within 48 h of onset (4 days vs. 2 days, P=0·014).

Hazy Blue Worlds: A Holistic Aerosol Model for Uranus and Neptune, Including Dark Spots.

We present a reanalysis (using the Minnaert limb-darkening approximation) of visible/near-infrared (0.3-2.5 µm) observations of Uranus and Neptune made by several instruments. We find a common model of the vertical aerosol distribution i.e., consistent with the observed reflectivity spectra of both planets, consisting of: (a) a deep aerosol layer with a base pressure >5-7 bar, assumed to be composed of a mixture of H2S ice and photochemical haze; (b) a layer of photochemical haze/ice, coincident with a layer of high static stability at the methane condensation level at 1-2 bar; and (c) an extended layer of photochemical haze, likely mostly of the same composition as the 1-2-bar layer, extending from this level up through to the stratosphere, where the photochemical haze particles are thought to be produced. For Neptune, we find that we also need to add a thin layer of micron-sized methane ice particles at ∼0.2 bar to explain the enhanced reflection at longer methane-absorbing wavelengths. We suggest that methane condensing onto the haze particles at the base of the 1-2-bar aerosol layer forms ice/haze particles that grow very quickly to large size and immediately "snow out" (as predicted by Carlson et al. (1988), https://doi.org/10.1175/1520-0469(1988)045<2066:CMOTGP>2.0.CO;2), re-evaporating at deeper levels to release their core haze particles to act as condensation nuclei for H2S ice formation. In addition, we find that the spectral characteristics of "dark spots", such as the Voyager-2/ISS Great Dark Spot and the HST/WFC3 NDS-2018, are well modelled by a darkening or possibly clearing of the deep aerosol layer only.

Testicular signaling is the potential target of perfluorooctanesulfonate-mediated subfertility in male mice.

Perfluorooctanesulfonate (PFOS) was produced and used by various industries and in consumer products. Because of its persistence, it is ubiquitous in air, water, soil, wildlife, and humans. Although the adverse effects of PFOS on male fertility have been reported, the underlying mechanisms have not yet been elucidated. Here, for the first time, the effects of PFOS on testicular signaling, such as gonadotropin, growth hormone, insulin-like growth factor, and inhibins/activins were shown to be directly related to male subfertility. Sexually mature 8-wk-old CD1 male mice were administered by gavages in corn oil daily with 0, 1, 5, or 10 mg/kg PFOS for 7, 14, or 21 days. Serum concentrations of testosterone and epididymal sperm counts were significantly lower in the mice after 21 days of the exposure to the highest dose compared with the controls. The expression levels of testicular receptors for gonadotropin, growth hormone, and insulin-like growth factor 1 were considerably reduced on Day 21 in mice exposed daily to 10 or 5 mg/kg PFOS. The transcript levels of the subunits of the testicular factors (i.e., inhibins and activins), Inha, Inhba, and Inhbb, were significantly lower on Day 21 of daily exposure to 10, 5, or 1 mg/kg PFOS. The mRNA expression levels of steroidogenic enzymes (i.e., StAR, CYP11A1, CYP17A1, 3beta-HSD, and 17beta-HSD) were notably reduced. Therefore, PFOS-elicited subfertility in male mice is manifested as progressive deterioration of testicular signaling.

Notes from some crypt watchers: regulation of renewal in the mouse intestinal epithelium.

The mouse intestinal epithelium undergoes rapid renewal throughout life, thereby requiring continuous coordination of its cellular proliferation, differentiation, and death programs. Recent advances in our understanding of this process have highlighted some of the molecules that regulate renewal and their potential roles in gut neoplasia.

Microwave observations reveal the deep extent and structure of Jupiter's atmospheric vortices.

Jupiter's atmosphere has a system of zones and belts punctuated by small and large vortices, the largest being the Great Red Spot. How these features change with depth is unknown, with theories of their structure ranging from shallow meteorological features to surface expressions of deep-seated convection. We present observations of atmospheric vortices using the Juno spacecraft's Microwave Radiometer. We found vortex roots that extend deeper than the altitude at which water is expected to condense, and we identified density inversion layers. Our results constrain the three-dimensional structure of Jupiter's vortices and their extension below the clouds.

Ecotoxicological study on sediments of Mai Po marshes, Hong Kong using organisms and biomarkers.

Sediments from Mai Po Ramsar site, Hong Kong were in general shown to be highly toxic based on the results of four toxicity tests (Microtox solid-phase test, Daphnia mortality test, algal [Microcystis aeruginosa] growth inhibition test and ryegrass [Lolium perenne] seed germination/root elongation test). Sediment of the mudflat (which is open to Deep Bay, i.e., the pollution source) was the most toxic while sediment of gei wai 24g (an enclosed freshwater pond) was the least toxic. Results of biomarker studies (tilapia hepatic metallothionein; glutathione (GSH) and EROD activity using H4IIE rat hepatoma cell) were also concordant with those in the toxicity tests. Significant liner relationships (p<0.01) were found between GSH contents in the rat hepatoma cells and PAHs, OCPs contents in the sediment extracts. It is recommended that the present suite of bioassays is useful and is biologically relevant for future ecotoxicological studies focusing on similar wetlands.

Bacterial communities in PAH contaminated soils at an electronic-waste processing center in China.

Surface soils from Guiyu, China (an intense e-waste processing center) were analyzed for persistent organic pollutants (POPs) and variations in composition of the resident bacterial communities. Denaturing Gradient Gel Electrophoresis analysis of bacterial 16S rRNA gene showed that e-waste pollution altered the bacterial community structure by promoting changes in species composition and species richness. Bacterial diversity was not decreased at e-waste open-burning sites, compared with a non e-waste site (reservoir site), due to flourishing of possible POPs-consuming bacterial cohorts. PAH-incubated experiments confirmed that different levels of PAHs might affect the bacterial community by suppressing or favoring certain groups of bacteria, for instance, uncultured Clostridium sp. and Massilia sp., respectively. Taxonomic analysis indicated beta-proteobacteria and Firmicutes were abundant bacterial lineages in PAH-polluted soils. This study is the first reporting bacterial community structures at e-waste processing sites, and indicated that crude processing of e-waste has become a biohazard to the terrestrial environment warranting more extensive studies of microbial communities at e-waste polluted environments.

Risk assessment of residual DDTs in freshwater and marine fish cultivated around the Pearl River Delta, China.

Six species of freshwater fish collected from 10 fishponds in Shunde and Zhongshan, China, four species of marine fishes collected from different mariculture farms [four in Hong Kong (Tung Lung Chau, Ma Wan, Cheung Chau and Kat O) and two in mainland China (Daya Bay and Shenzhen)] together with feed (both trash fish and commercial pellets) and sediment were analyzed for DDTs. Total DDTs in freshwater fish flesh decreased in the order of: carnivores [1742 microg/kg lipid weight (l.w.)] > herbivores (165 microg/kg, l.w.) > omnivores (42.5 microg/kg, l.w.), with the highest concentration detected in mandarin fish (Siniperca chuatsi) (2641 microg/kg, l.w.). For marine fish, snubnose pompano (Trachinotus blochii) and orange-spotted grouper (Epinephelus coioides) collected in Ma Wan contained elevated levels of total DDTs (2590 and 2034 microg/kg l.w., respectively). Trash fish used in both freshwater and marine fish farms contained significantly higher levels (86.5-641 microg/kg l.w.) (p < 0.05) of DDTs than in commercial pellets, but correlations between DDT levels in fish feed and muscle were not significant. The elevated biota-sediment accumulating factor for tilapia (Tilapia mossambicus) (24.1) indicated that accumulation of DDTs from sediment to the fish was evident. It can be concluded that trash fish should not be used for fish culture in order to lower the level of residual DDTs in fish muscle.

Food waste-based pellets for feeding grass carp (Ctenopharyngodon idellus): Adding baker's yeast and enzymes to enhance growth and immunity.

Protein rich food waste could be used as raw materials for making fish feed pellets, which would diminish the volume of dumped waste into landfills. This study investigated the use of food waste (FW) based pellets composing of 75% food wastes derived from plant materials (cereals, fruit and vegetables) supplemented with yeast and the mixture of bromelain and papain to feed grass carp (Ctenopharyngodon idellus). Generally, improved growth performance (in terms of feed conversion ratio, protein efficiency ratio and relative weight gain) was observed in the diet groups supplemented with yeast (Saccharomyces cerevisiae). The most optimal dose was 25 g/kg yeast with enzymes (bromelain and papain, at the ratio of 1:1) and protein utilization was enhanced. Fish immunity was also stimulated, which indicated by the higher nitroblue tetrazolium and bactericidal activities. Moreover, resistance against Aeromonas hydrophilia was enhanced. It is envisaged that food waste could be widely used as feeds for culturing herbivorous fish and adding supplements such as baker's yeast and enzymes will further enhance the feed conversion ratio and fish immunity.