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In this study, we objectively focus on the relationship between the number of coronavirus (COVID-19) cases and key climate variables. We found that the risk of COVID-19 was approximately doubled during warm summer months when the aerosol molecules are likely stimulated by temperature and rainfall. Given that India is currently emerging as the new epicenter for the third and fourth outbreaks of COVID-19, we selected four key hotspot states-Maharashtra, Andhra Pradesh, Kerala, and Tamil Nadu - to closely look into the impact of climate variables on the spread of COVID-19 infected cases during 2020 and 2021. We found that COVID-19 is most active in temperature between 27°C and 32°C, while it is active in monthly average rainfall between 250 mm and 350 mm. This study further confirms that, although temperature and rainfall are not the initial triggers of COVID-19, both variables seem to play significant roles in spreading COVID-19 in India, especially during the summer season of 2020 and 2021, when the Indian summer monsoon was stronger in these four states.

This research synthesises two evaluations of a local level climate change adaptation and planning process in the southernmost coastal region, Kanyakumari, India which was supported through community-based appraisals. First, understanding the public perception of climate change factors is crucial in generating support for climate change response. Second, generating enough grass-root level support from the local population to assess the long-term climate change impacts on decision-making to design the adaptation strategies for sea-level rise. These two results highlight the level of understanding and awareness of climate change’s impact by the local population in the coastal region of Kanyakumari. A well-designed questionnaire with structured interviews, to collect data on local knowledge and local perception of climate change and sea-level rise from 100 respondents was distributed each in 44 coastal villages in the study area. The finding showed that 20.7% of the local population have knowledge of climate change and its impacts and 18.4% of the population agreed that the impact of sea-level rise is experienced in the coastal region. This study is to provide insight into the communities’ knowledge of the adaptive capacity of the local population to cope with climate change towards the treaty of sea-level rise.

Nanotechnology has grasped the attention of scientists in several fields during the past decade because of its huge role in developing unique characteristics and behaviors for materials, as it deals with understanding, controlling, and modification of matter at the atomic level in the range of 0.1–100 nm (10–9mm). Nanotechnology could be a paradigm shift in the civil engineering field as the studies showed that inducing different types of nanoparticles in concrete contributed dramatically to improving the mechanical characteristics and durability of concrete as well as creating innovative properties such as self-sensing, self-cleaning, fire-resisting, etc. This paper will show the recent results that were concluded by researchers about the effect of adding nanoparticles in construction materials and especially the effect of multi-walled carbon nanotubes as an enhancing material.

We investigate suspended particles collected from the upper mixed layer in the inner shelf of the southern East China Sea during autumn 2013 for carbon and nitrogen (POC and PN) contents and their isotope compositions (δ13C and δ15N) along with hydrographic parameters to understand the sources and dynamics of particulate organic matter (POM) in the study area. Results indicated that the extensive hydrological processes affect the biogeochemical composition of suspended POM, as revealed by the horizontally mixing POM and the spatial variation of δ15N and molar C/N ratio. Low C/N (2.4–6.5) and a weak correlation between POC and in situ chlorophyll fluorescence suggested that POM is dominated by the recently formed and well‐preserved planktonic OM. By fitting the linear correlation between δ13C and POC data with a photosynthetic fractionation model, we further disentangled dynamic controls of phytoplankton production and species diversity on δ13C variability (−24.3 to −21.3‰), emphasizing the constant effect of productivity‐derived POC on δ13C (0.02‰ per μg/L). The δ15N variability (2.3–7.4‰) is largely controlled by the mixing of isotopically different nitrogen sources, in which the importance of biological nitrogen fixation is unfolded based on the small δ15N and the negative correlation between δ15N of POM and seawater temperature. This implies that Kuroshio‐induced biological N fixation plays an important role in supporting the marine production in the East China Sea. These hydrologically driven δ13C and δ15N changes of marine productivity‐derived POM suggest that internal biophysical dynamics rather than terrestrial versus marine OM mixing largely control the C and N compositional variability in the shelf seas. Mixing of water masses on the shallow continental shelf of the East China Sea is thought to impact biogeochemical dynamics of suspended particulate organic matter on seasonal basis, but the mechanisms involved remain unclear. In this study, we measured carbon and nitrogen elemental and isotopic composition of particulate organic matter in the upper mixed layer along with hydrographic parameters during autumn season when the upwelled Kuroshio water travels closer to the coast. Results indicated that particulate organic matter is dominated by two sources of plankton‐derived organic matter that mixed horizontally by hydrodynamics. In addition, the upwelled Kuroshio contribute to marine productivity significantly by inducing biological nitrogen fixation on the shelf; the region is otherwise N‐starved. These findings based on observational and analytical results can help marine biogeochemists understand how carbon and nitrogen isotopes varied seasonally by the impact of offshore current over the river‐dominated shallow shelf, although the influence of Kuroshio on marine fisheries is beyond the scope of our investigation. Hydrological conditions largely control the biogeochemical composition of suspended particulate organic matter in the southern East China SeaParticulate organic matter in the upper mixed layer is mainly of marine origin, despite having wide ranges of δ13C and δ15N valuesKuroshio‐induced biological nitrogen fixation is important for marine production in the southern East China Sea

The controlled permeable formwork (CPF) liner is a novel way to improving the quality of cover zone of concrete. This technique is used to remove excess water and trapped air from the near surface of fresh concrete while retaining small particles such as cement and other fine particles. As a result, the concrete’s surface zone has a lower water-to-cement ratio, lower surface porosity and more cement content. This study looked at the effect of CPF liner on concrete’s strength, durability and chemical resistance. Three different water-to-cement ratios (0.48, 0.41, and 0.31) were used to cast concrete samples against a CPF liner and an impermeable formwork (IMF). At various ages, the compressive strength, water absorption, sorptivity, hydrochloric acid and sulphate resistance tests were performed. The findings revealed that CPF concretes had an excellent resistance to water absorption and sorptivity by 15–30% and 32–67% respectively. The residual compressive strength of CPF concrete was more by 9–144% compared to IMF concretes under hydrochloric acid environment.

Tropical rivers deliver ∼60% of particulate organic carbon to the world ocean. However, compositions and loadings of sedimentary organic matter (OM) from tropical small mountainous rivers are largely unknown. Here, we provide an initial constrain on sources of sedimentary OM from 28 fluvial systems across Luzon in the Philippines by measuring total organic carbon (TOC), total nitrogen (TN), stable carbon isotope (δ13C) and radiocarbon activity of TOC (expressed as fraction modern—Fm), as well as grain size and mineral surface area (SA) of sediments. Results indicate that sediments in Luzon rivers contain both contemporary and 14C‐depleted OM (Fm: 0.71–1.06, mean 0.97 ± 0.07) with a wide range of δ13C values (−28.3‰ to −17.7‰, −24.9 ± 2.2‰). This is attributed to the OM sources originated from modern surface soil and 14C‐depleted subsoil and deep soil vegetated by C3 and C4 plants, with mean fraction of C3 plant at 80% ± 11%. Minor input from bedrock may also contribute to the 14C‐depleted OM in sediments, accounting for 6% ± 6%. Sediments in most rivers are featured by low OC loadings (OC/SA ratio < 0.4 mg C m−2), owing either to a less OM input or intensive OM degradation. The estimated yields of particulate OC from Luzon vary between 3.2 and 3.7 t km−2yr−1, which is higher than most tropical large rivers. C3 and C4 plants underlain by modern surface soils represent the main contribution to organic matter (OM) found in Luzon river sedimentsDegraded OM in subsoils and deep soils or bedrock contribute to radiocarbon (14C)‐depleted OM in Luzon riversThe yields of particulate organic carbon from tropical small mountainous rivers on Luzon are much higher than that of other tropical large river systems C3 and C4 plants underlain by modern surface soils represent the main contribution to organic matter (OM) found in Luzon river sediments Degraded OM in subsoils and deep soils or bedrock contribute to radiocarbon (14C)‐depleted OM in Luzon rivers The yields of particulate organic carbon from tropical small mountainous rivers on Luzon are much higher than that of other tropical large river systems