Pure Earth

In Mexico, the main source of lead (Pb) exposure is the use of lead-glazed ceramic (LGC). Curing is a traditional technique employed to seal the pores of ceramic, enhancing resistance to high temperatures and moisture absorption. One common belief, sometimes promoted by governmental sources, is that this practice can also remove Pb from LGC. In this study, we evaluated the effect of three traditional curing methods (oil/heat, boiling water/lard, and garlic/boiling vinegar) on Pb detection, concentration and leaching in three LGC pieces. Before and after curing, detection (LumetallixTM and sodium rhodizonate) and concentration (XRF) were measured; meanwhile, leaching after curing was evaluated by ICP-MS in a simulated solution. All pieces were positive for Pb detection. Mean Pb concentration before curing was 164,400 ppm and increased on average to 266,700 ppm after curing, exceeding the limits established for ceramics (100 ppm). The highest level of Pb leaching was in the piece cured with oil/heat (378.18 ppm) followed by garlic/boiling vinegar (2.6 ppm), both exceeding the Mexican Normativity for leaching (0.5 ppm). We find that traditional curing should not be considered as a practice to remove Pb. Even worse, it may increase its availability and leach into food, increasing the health risk to consumers.

Despite the global phase-out of leaded gasoline, lead poisoning is estimated to cause 5.5 million premature deaths and the loss of 765 million IQ points annually. However, the contributions of different lead exposure sources to blood lead levels (BLLs) are poorly understood. We conducted a systematic literature review using the Scopus database, examining 39 studies that attribute BLLs to specific sources of lead exposure, published since the year 2000 and with sample sizes >100. The 39 studies were from 26 countries; 22 were from low- and middle-income countries, with an average sample size of 1003 participants. Twenty-three of the studies reported absolute BLL impacts (μg/L) from lead exposure sources, other studies reported odds ratios for elevated BLLs (>50 or>100μg/L). Averaged across the studies, the BLL impacts were 42.3μg/L from living near industrial lead pollution hotspots, 31.4μg/L from occupational and take-home exposure, 28.0μg/L from deteriorated paint, 19.8μg/L from traditional medicines and cosmetics, 19.3μg/L from foodware (glazed ceramics and melamine plates), 17.3μg/L from smoking, 15.4μg/L from foods, and 12.9μg/L from geophagy. Only one of the reviewed studies assessed the BLL impact of metal cookware, and did not find a significant relationship with BLLs. However, the statistical power of the attributional studies to detect relationships with BLLs was often limited. Future studies should investigate the ingestion routes from industrial pollution, the contamination of foods and spices, BLL impacts of lead-contaminated metal cookware, and traditional medicines administered to young children and infants.

It is usually not straightforward to work with the category of perverse sheaves on a variety using only its definition as a heart of a $t$-structure. In this paper, the category of perverse sheaves on a smooth toric variety with its orbit stratification is described explicitly as a category of finite-dimensional modules over an algebra. An analogous result is also established for various categories of equivariant perverse sheaves, which in particular gives a description of perverse sheaves on toric orbifolds, and we also compare the derived category of the category of perverse sheaves to the derived category of constructible sheaves.

Определение категории превратных пучков на многообразии как сердцевины $t$-структуры не всегда приспособлено для вычислений. В данной работе представлено описание категории превратных пучков на гладком торическом многообразии как категории конечномерных модулей над алгеброй. Аналогичный результат получен для некоторых категорий эквивариантных превратных пучков, что, в частности, дает описание превратных пучков на торических орбифолдах. Также сравниваются производная категория абелевой категории превратных пучков и производная категория конструктивных пучков. Библиография: 20 наименований.

PURPOSE: Femoroacetabular impingement (FAI) is increasingly recognized as a cause for hip and groin pain in young, active patients. When symptomatic FAI limits performance and nonoperative measures fail, surgery is necessary. Recovery durations and successful return to sport (RTS) rates vary, with current guidelines recommending RTS at 9 months post-surgery. This study aimed to assess the time to RTS following hip arthroscopy for FAI syndrome. The purpose was to assess if individuals safely RTS sooner than 9 months. METHODS: Patients undergoing hip arthroscopy for FAI performed by one surgeon were retrospectively contacted. The surgeon prescribed an accelerated rehabilitation protocol, emphasizing early low-impact exercise and rapid progression of weightbearing, range of motion, and strength training. A Modified Harris Hip Score (HHS) and Copenhagen Hip and Groin Outcome Score (HAGOS) were administered at 26 ± 11 months following surgery. Pre- and post-injury activity level, time to RTS, complications and revision surgeries were recorded. RESULTS: This cohort comprised 57 athletes (35 females, 22 males, 38.0 ± 13.9 years old, 31 recreational and 26 competitive-level athletes). 45 patients RTS at or above pre-injury levels (Figure 1), with a majority (55.6%) of patients returning to sport in <6 months. Of the 12 patients that did not RTS, 5 (41.7%) did not return for reasons other than their hip. The mean HAGOS of those able to RTS (65.6) was significantly more than for those who did not (54.0; p = 0.027). The mean Modified HHS for those returning to sport (89.4) was greater than those who did not (81.9; p = 0.143). CONCLUSIONS: This study provides evidence that rapid, progressive rehabilitation following hip arthroscopy for FAI is a reliable approach for facilitating athletes' RTS without increased risks.

Documentar la situación de intoxicación por plomo en población pediátrica en México, identificar poblaciones con mayor riesgo y presentar recomendaciones de política pública para afrontar el problema. Material y métodos. Se realizó un análisis integrado de la Encuesta Nacional de Salud y Nutrición Continua 2022-2023. Las concentraciones de plomo se midieron en sangre capilar de 1,747 menores de 1-4 años por voltamperometría de redisolución anódica. Se estimó la prevalencia de intoxicación (PbS>5μg/dL) en estratos sociodemográficos y de vulnerabilidad social. Se identificaron poblaciones con mayor riesgo de intoxicación. La prevalencia de intoxicación nacional fue de 17.2%, 29% en población indígena, 25% en aquélla con desnutrición crónica, 25% con mayores niveles de carencias; 20% en zonas rurales y urbanas, 12% en metropolitanas. No se encontraron diferencias por sexo. El mayor riesgo de intoxicación (52%) se presenta en población indígena, con desnutrición crónica, residente en zonas rurales y que utiliza barro vidriado; un riesgo 15 veces mayor al perfil de menor vulnerabilidad (3.5%). La intoxicación por plomo es un problema de justicia ambiental. Es necesario implementar una estrategia nacional de remoción de la principal fuente de exposición; un sistema de vigilancia epidemiológica para la identificación y atención de casos y un biomonitoreo poblacional en población pediátrica y mujeres embarazadas; es imperante la vigilancia de normas vigentes.

Latar Belakang: Ibu hamil di Indonesia selama tahun 2019 cakupan ibu hamil relatif naik pada kejadian kecemasan. Bila diperbandingkan dengan target Rencana Strategis Kementerian Kesehatan tahun 2019 yang sejumlah 80%, capaian target yaitu sebesar 88,54%. Tujuan: Untuk mengenal mengetahui Hubungan sumber informasi, peran bidan, dan dukungan keluarga dengan kejadian kecemasan ibu hamil di masa pandemi Covid-19 di Puskesmas Padarincang Kabupaten Serang-Banten tahun 2021. Metode: Metode yang dipergunakan teknik analitik dengan pendekatan Cross-Sectional. Populasi penelitian ini yakni ibu hamil sejumlah 1.289 dan teknik sampel dalam penelitian ini mempergunakan non probability yaitu teknik purposive sampling dengan non random sampling. Pengumpulan data menggunakan kuesioner. Metode analisa data memakai uji Chi-Square dengan SPSS. Hasil: Hasil statistik didapatkan nilai Sumber Informasi P-Value (0,000) &lt; a (0,05), Peran Bidan P-Value (0,376) &gt; a (0,05), Dukungan Keluarga P-Value (0,000) &lt; a (0,05). Kesimpulan: Terdapat hubungan sumber informasi, peran bidan, dan dukungan keluarga dengan kejadian kecemasan ibu hamil.

Subject of research: technology for restoring the working area of a stamp tool, the structure and properties of the deposited layer of the restored stamp surface.&#x0D; Purpose of research: to develop a technology for restoring the working area of a hot deformation die insert for the formation of a gradient structure and properties of the metal over the cross section of the deposited zone.&#x0D; Methods and object of research: a technology for restoring the insertion of a worn hot-forming stamp on the beam of the front axle of a KAMAZ truck using two-layer electric arc surfacing with one type of electrode wire is presented. To obtain a gradient structure in the section of the working area of the die, heat treatment is proposed, which consists in tempering the die after the first surfacing at a temperature of 62010C, and after the second surfacing at a temperature of 52010C.&#x0D; Main results of research: it was found that after the restoration of the hot deformation die insert, the hardness of the deposited metal of the first (deep) layer was 3436 HRC, the structure was tempered troostite, the hardness of the second (outer) layer was 4246 НRC, structure tempered martensite and troostomare-tensite. This ensures high wear resistance of surface layers and crack resistance in the depth of the die metal.